Best Pdf Library: Syllabus

Showing posts with label Syllabus. Show all posts

#155 Genetic technology Syllabus 2016 -2048

shahid Mandokhail A2 , Genetic Technology

19.1 Principles of genetic technology
19.2 Genetic technology applied to medicine
19.3 Genetically modified organisms in agriculture

The discovery of the structure of DNA by Watson and Crick in the early 1950s and discoveries since have led to many applications of gene technology in areas of medicine, agriculture and forensic science. This section relies heavily on prior knowledge of DNA structure and protein synthesis studied in the section on Nucleic acids and protein synthesis. Where possible, candidates should carry out practical work using electrophoresis, either with DNA or specially prepared dyes used to represent DNA or proteins.

Candidates will be expected to use the knowledge gained in this section to solve problems in familiar and unfamiliar contexts.

Learning outcomes

Candidates should be able to:

19.1 Principles of genetic technology

Genetic engineering involves the manipulation of naturally occurring processes and enzymes.

Genome sequencing gives information about the location of genes and provides evidence for the evolutionary links between organisms.

a) define the term recombinant DNA

b) explain that genetic engineering involves the extraction of genes from one organism, or the synthesis of genes, in order to place them in another organism (of the same or another species) such that the receiving organism expresses the gene product

c) describe the principles of the polymerase chain reaction (PCR) to clone and amplify DNA (the role of Taq polymerase should be emphasised)

d) describe and explain how gel electrophoresis is used to analyse proteins and nucleic acids, and to distinguish between the alleles of a gene (limited to the separation of polypeptides and the separation of DNA fragments cut with restriction endonucleases)

e) describe the properties of plasmids that allow them to be used in gene cloning

f) explain why promoters and other control sequences may have to be transferred as well as the desired gene

g) explain the use of genes for fluorescent or easily stained substances as markers in gene technology

h) explain the roles of restriction endonucleases, reverse transcriptase and ligases in genetic engineering

i) explain, in outline, how microarrays are used in the analysis of genomes and in detecting mRNA in studies of gene expression

19.2 Genetic technology applied to medicine

a) define the term bioinformatics

b) outline the role of bioinformatics following the sequencing of genomes, such as those of humans and parasites, e.g. Plasmodium (details of methods of DNA sequencing are not required)

c) explain the advantages of producing human proteins by recombinant DNA techniques (reference should be made to some suitable examples, such as insulin, factor VIII for the treatment of haemophilia and adenosine deaminase for treating severe combined immunodeficiency (SCID))

d) outline the advantages of screening for genetic conditions (reference may be made to tests for specific genes such as those for breast cancer, BRCA1 and BRCA2, and genes for haemophilia, sickle cell anaemia, Huntington’s disease and cystic fibrosis)

e) outline how genetic diseases can be treated with gene therapy and discuss the challenges in choosing appropriate vectors, such as viruses, liposomes and naked DNA (reference may be made to SCID, inherited eye diseases and cystic fibrosis)

f) discuss the social and ethical considerations of using gene testing and gene therapy in medicine (reference should be made to genetic conditions for which treatments exist and where none exist, also to IVF, embryo biopsy and preselection and to therapeutic abortions)

g) outline the use of PCR and DNA testing in forensic medicine and criminal investigations

19.3 Genetically modified organisms in agriculture

The ability to manipulate genes has many potential benefits in agriculture, but the implications of releasing genetically modified organisms (GMOs) into the environment are subject to much public debate in some countries.

a) explain the significance of genetic engineering in improving the quality and yield of crop plants and livestock in solving the demand for food in the world, e.g. Bt maize, vitamin A enhanced rice (Golden riceTM) and GM salmon

b) outline the way in which the production of crops such as maize, cotton, tobacco and oil seed rape may be increased by using varieties that are genetically modified for herbicide resistance and insect resistance

c) discuss the ethical and social implications of using genetically modified organisms (GMOs) in food production

#144 Biodiversity, classification and conservation Syllabus 2016 - 2018

shahid Mandokhail A2 , Biodiversity

18.1 Biodiversity
18.2 Classification
18.3 Conservation

The biodiversity of the Earth is threatened by human activities and climate change. Classification systems attempt to put order on the chaos of all the organisms that exist on Earth. Field work is an important part of a biological education to appreciate this diversity and find out how to analyse it. There are opportunities in this section for candidates to observe different species in their locality and assess species distribution and abundance. Conserving biodiversity is a difficult task but is achieved by individuals, local groups, national and international organisations. Candidates should appreciate the threats to biodiversity and consider the steps taken in conservation, both locally and globally.

Candidates will be expected to use the knowledge gained in this section to solve problems in familiar and unfamiliar contexts.

Learning outcomes

Candidates should be able to:

18.1 Biodiversity

Biodiversity is much more than a list of all the species in a particular area.

a) define the terms species, ecosystem and niche

b) explain that biodiversity is considered at three different levels:
• variation in ecosystems or habitats
• the number of species and their relative abundance
• genetic variation within each species

c) explain the importance of random sampling in determining the biodiversity of an area

d) use suitable methods, such as frame quadrats, line transects, belt transects and mark-release-recapture, to assess the distribution and abundance of organisms in a local area

e) use Spearman’s rank correlation and Pearson’s linear correlation to analyse the relationships between the distribution and abundance of species and abiotic or biotic factors

f) use Simpson’s Index of Diversity (D) to calculate the biodiversity of a habitat and state the significance of different values of D

18.2 Classification

Organisms studied locally may be used to show how hierarchical classification systems are organised.

a) describe the classification of species into the taxonomic hierarchy of domain, kingdom, phylum, class, order, family, genus and species

b) outline the characteristic features of the three domains Archaea, Bacteria and Eukarya

c) outline the characteristic features of the kingdoms Protoctista, Fungi, Plantae and Animalia

d) explain why viruses are not included in the three domain classification and outline how they are classified, limited to type of nucleic acid (RNA or DNA) and whether these are single stranded or double stranded

18.3 Conservation

Maintaining biodiversity is important for many reasons. Actions to maintain biodiversity must be taken at local, national and global levels.

It is important to conserve ecosystems as well as individual species.

a) discuss the threats to the biodiversity of aquatic and terrestrial ecosystems (see 18.1b)

b) discuss the reasons for the need to maintain biodiversity

c) discuss methods of protecting endangered species, including the roles of zoos, botanic gardens, conserved areas (national parks and marine parks), ‘frozen zoos’ and seed banks

d) discuss methods of assisted reproduction, including IVF, embryo transfer and surrogacy, used in the conservation of endangered mammals

e) discuss the use of culling and contraceptive methods to prevent overpopulation of protected and non-protected species

f) use examples to explain the reasons for controlling alien species

g) discuss the roles of non-governmental organisations, such as the World Wide Fund for Nature (WWF) and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), in local and global conservation

h) outline how degraded habitats may be restored with reference to local or regional examples

#137 Selection and Evolution Syllabus 2016 - 2018

shahid Mandokhail A2 , Selection and Evolution

17.1 Variation
17.2 Natural and artificial selection
17.3 Evolution

Charles Darwin and Alfred Russel Wallace proposed a theory of natural selection to account for the evolution of species in 1858. A year later, Darwin published On the Origin of Species providing evidence for the way in which aspects of the environment act as agents of selection and determine which variants survive and which do not. The individuals best adapted to the prevailing conditions succeed in the ‘struggle for existence’.

Candidates will be expected to use the knowledge gained in this section to solve problems in familiar and unfamiliar contexts.

Learning outcomes

Candidates should be able to:

17.1 Variation

The variation that exists within a species is categorised as continuous and discontinuous. The environment has considerable influence on the expression of features that show continuous (or quantitative) variation.

a) describe the differences between continuous and discontinuous variation and explain the genetic basis of continuous (many, additive genes control a characteristic) and discontinuous variation (one or few genes control a characteristic) (examples from 16.2f may be used to illustrate discontinuous variation; height and mass may be used as examples of continuous variation)

b) explain, with examples, how the environment may affect the phenotype of plants and animals

c) use the t-test to compare the variation of two different populations (see Mathematical requirements)

d) explain why genetic variation is important in selection

17.2 Natural and artificial selection

Populations of organisms have the potential to produce large numbers of offspring, yet their numbers remain fairly constant year after year.

Humans use selective breeding (artificial selection) to improve features in ornamental plants, crop plants, domesticated animals and livestock.

a) explain that natural selection occurs as populations have the capacity to produce many offspring that compete for resources; in the ‘struggle for existence’ only the individuals that are best adapted survive to breed and pass on their alleles to the next generation

b) explain, with examples, how environmental factors can act as stabilising, disruptive and directional forces of natural selection

c) explain how selection, the founder effect and genetic drift may affect allele frequencies in populations

d) use the Hardy–Weinberg principle to calculate allele, genotype and phenotype frequencies in populations and explain situations when this principle does not apply

e) describe how selective breeding (artificial selection) has been used to improve the milk yield of dairy cattle

f) outline the following examples of crop improvement by selective breeding:
• the introduction of disease resistance to varieties of wheat and rice
• the incorporation of mutant alleles for gibberellin synthesis into dwarf varieties so increasing yield by having a greater proportion of energy put into grain
• inbreeding and hybridisation to produce vigorous, uniform varieties of maize

17.3 Evolution

Isolating mechanisms can lead to the accumulation of different genetic information in populations, potentially leading to new species.

Over prolonged periods of time, some species have remained virtually unchanged, others have changed significantly and many have become extinct.

a) state the general theory of evolution that organisms have changed over time

b) discuss the molecular evidence that reveals similarities between closely related organisms with reference to mitochondrial DNA and protein sequence data

c) explain how speciation may occur as a result of geographical separation (allopatric speciation), and ecological and behavioural separation (sympatric speciation)

d) explain the role of pre-zygotic and post-zygotic isolating mechanisms in the evolution of new species

e) explain why organisms become extinct, with reference to climate change, competition, habitat loss and killing by humans

#117 Control and co-ordination Syllabus 2016-2018

shahid Mandokhail A2 , Control & co-ordination

15.1 Control and co-ordination in mammals
15.2 Control and co-ordination in plants

All the activities of multicellular organisms require co-ordinating, some very rapidly and some more slowly. The nervous system and the endocrine system provide co-ordination in mammals. Similar co-ordination systems exist in plants.

Candidates will be expected to use the knowledge gained in this section to solve problems in familiar and unfamiliar contexts.

Learning outcomes

Candidates should be able to:

15.1 Control and co-ordination in mammals

The nervous system provides fast communication between receptors and effectors.
Transmission between neurones takes place at synapses.

a) compare the nervous and endocrine systems as communication systems that co-ordinate responses to changes in the internal and external environment (see 14.1a and 14.1b)

b) describe the structure of a sensory neurone and a motor neurone

c) outline the roles of sensory receptor cells in detecting stimuli and stimulating the transmission of nerve impulses in sensory neurones (a suitable example is the chemoreceptor cell found in human taste buds)

d) describe the functions of sensory, relay and motor neurones in a reflex arc

e) describe and explain the transmission of an action potential in a myelinated neurone and its initiation from a resting potential (the importance of sodium and potassium ions in impulse transmission should be emphasised)

f) explain the importance of the myelin sheath (saltatory conduction) in determining the speed of nerve impulses and the refractory period in determining their frequency

g) describe the structure of a cholinergic synapse and explain how it functions, including the role of calcium ions

h) outline the roles of synapses in the nervous system in allowing transmission in one direction and in allowing connections between one neurone and many others (summation, facilitation and inhibitory synapses are not required)

i) describe the roles of neuromuscular junctions, transverse system tubules and sarcoplasmic reticulum in stimulating contraction in striated muscle

j) describe the ultrastructure of striated muscle with particular reference to sarcomere structure

k) explain the sliding filament model of muscular contraction including the roles of troponin, tropomyosin, calcium ions and ATP.

The endocrine system is a slower system that controls long-term changes. Fertility may be controlled by use of hormones.

l) explain the roles of the hormones FSH, LH, oestrogen and progesterone in controlling changes in the ovary and uterus during the human menstrual cycle

m) outline the biological basis of contraceptive pills containing oestrogen and/or progesterone

15.2 Control and co-ordination in plants

Plant co-ordination systems involve rapid responses as in the case of the Venus fly trap, but also complex interactions between plant growth regulators, such as auxin and gibberellin.

Plants respond quite differently to different concentrations of plant growth regulators.

a) describe the rapid response of the Venus fly trap to stimulation of hairs on the lobes of modified leaves and explain how the closure of the trap is achieved

b) explain the role of auxin in elongation growth by stimulating proton pumping to acidify cell walls

c) describe the role of gibberellin in the germination of wheat or barley

d) explain the role of gibberellin in stem elongation including the role of the dominant allele, Le, that codes for a functioning enzyme in the gibberellin synthesis pathway, and the recessive allele, le, that codes for a non-functional enzyme.

# 107 Homeostasis Syllabus 2016-2018

shahid Mandokhail A2 , Homeostasis

14.1 Homeostasis in mammals
14.2 Homeostasis in plants

Cells function most efficiently if they are kept in near constant conditions. Cells in multicellular animals are surrounded by tissue fluid. The composition, pH and temperature of tissue fluid are kept constant by exchanges with the blood as discussed in the section on Transport in mammals. In mammals, core temperature, blood glucose concentration and blood water potential are maintained within narrow limits to ensure the efficient operation of cells. Prior knowledge for this section includes an understanding that waste products are excreted from the body – a role that is fulfilled by the kidneys – and an outline of the structure and function of the nervous and endocrine systems. In plants, guard cells respond to fluctuations in environmental conditions and open and close stomata as appropriate for photosynthesis and conserving water.

Candidates will be expected to use the knowledge gained in this section to solve problems in familiar and unfamiliar contexts.

Learning outcomes

Candidates should be able to:

14.1 Homeostasis in mammals

Homeostasis in mammals requires complex systems to maintain internal conditions near constant.

The kidneys remove wastes from the blood and are the effectors for controlling the water potential of the blood.

a) discuss the importance of homeostasis in mammals and explain the principles of homeostasis in terms of internal and external stimuli, receptors, central control, co-ordination systems, effectors (muscles and glands)

b) define the term negative feedback and explain how it is involved in homeostatic mechanisms

c) outline the roles of the nervous system and endocrine system in co-ordinating homeostatic mechanisms, including thermoregulation, osmoregulation and the control of blood glucose concentration

d) describe the deamination of amino acids and outline the formation of urea in the urea cycle (biochemical detail of the urea cycle is not required)

e) describe the gross structure of the kidney and the detailed structure of the nephron with its associated blood vessels using photomicrographs and electron micrographs

f) describe how the processes of ultrafiltration and selective reabsorption are involved with the formation of urine in the nephron

g) describe the roles of the hypothalamus, posterior pituitary, ADH and collecting ducts in osmoregulation

h) explain how the blood glucose concentration is regulated by negative feedback control mechanisms, with reference to insulin and glucagon

i) outline the role of cyclic AMP as a second messenger with reference to the stimulation of liver cells by adrenaline and glucagon

j) describe the three main stages of cell signalling in the control of blood glucose by adrenaline as follows:

• hormone-receptor interaction at the cell surface
• formation of cyclic AMP which binds to kinase proteins

• an enzyme cascade involving activation of enzymes by phosphorylation to amplify the signal

k) explain the principles of operation of dip sticks containing glucose oxidase and peroxidase enzymes, and biosensors that can be used for quantitative measurements of glucose in blood and urine

l) explain how urine analysis is used in diagnosis with reference to glucose, protein and ketones

14.2 Homeostasis in plants

Stomatal aperture is regulated in response to the requirements for uptake of carbon dioxide for photosynthesis and conserving water.

a) explain that stomata have daily rhythms of opening and closing and also respond to changes in environmental conditions to allow diffusion of carbon dioxide and regulate water loss by transpiration

b) describe the structure and function of guard cells and explain the mechanism by which they open and close stomata

c) describe the role of abscisic acid in the closure of stomata during times of water stress (the role of calcium ions as a second messenger should be emphasised)

#98 Photosynthesis Syllabus 2016-2018

shahid Mandokhail A2 , Photosynthesis

13.1 Photosynthesis as an energy transfer process
13.2 Investigation of limiting factors
13.3 Adaptations for photosynthesis

Photosynthesis is the energy transfer process that is the basis of much of life on Earth. It provides the basis of most food chains providing energy directly or indirectly for all other organisms. In eukaryotes, the process occurs within chloroplasts. Candidates use their knowledge of plant cells and leaf structure from the section on Cell structure while studying photosynthesis. Various environmental factors influence the rate at which photosynthesis occurs.

Candidates will be expected to use the knowledge gained in this section to solve problems in familiar and unfamiliar contexts.

Learning outcomes

Candidates should be able to:

13.1 Photosynthesis as an energy transfer process

Light energy absorbed by chloroplast pigments in the light dependent stage of photosynthesis is used to drive reactions of the light independent stage that produce complex organic compounds.

Chromatography is used to identify chloroplast pigments and was also used to identify the intermediates in the Calvin cycle.

a) explain that energy transferred as ATP and reduced NADP from the light dependent stage is used during the light independent stage (Calvin cycle) of photosynthesis to produce complex organic molecules

b) state the sites of the light dependent and the light independent stages in the chloroplast

c) describe the role of chloroplast pigments (chlorophyll a, chlorophyll b, carotene and xanthophyll) in light absorption in the grana

d) interpret absorption and action spectra of chloroplast pigments e) use chromatography to separate and identify chloroplast pigments and carry out an investigation to compare the
chloroplast pigments in different plants (reference should be made to Rf values in identification)

f) describe the light dependent stage as the photoactivation of chlorophyll resulting in the photolysis of water and the transfer of energy to ATP and reduced NADP (cyclic and non-cyclic photophosphorylation should be described in outline only)

g) outline the three main stages of the Calvin cycle:

• fixation of carbon dioxide by combination with ribulose bisphosphate (RuBP), a 5C compound, to yield two molecules of GP (PGA), a 3C compound
• the reduction of GP to triose phosphate (TP) involving ATP and reduced NADP
• the regeneration of ribulose bisphosphate (RuBP) using ATP

h) describe, in outline, the conversion of Calvin cycle intermediates to carbohydrates, lipids and amino acids and their uses in the plant cell

13.2 Investigation of limiting factors

Environmental factors influence the rate of photosynthesis. Investigating these shows how they can

be managed in protected environments used in crop production.

a) explain the term limiting factor in relation to photosynthesis

b) explain the effects of changes in light intensity, carbon dioxide concentration and temperature on the rate of photosynthesis

c) explain how an understanding of limiting factors is used to increase crop yields in protected environments, such as glasshouses

d) carry out an investigation to determine the effect of light intensity or light wavelength on the rate of photosynthesis using a redox indicator (e.g. DCPIP) and a suspension of chloroplasts (the Hill reaction)

e) carry out investigations on the effects of light intensity, carbon dioxide and temperature on the rate of photosynthesis using whole plants, e.g. aquatic plants such as Elodea and Cabomba

13.3 Adaptations for photosynthesis

All the stages of photosynthesis occur in the chloroplast. Some tropical crops have C4 metabolism and adaptations to maximise carbon dioxide fixation.

a) describe the relationship between structure and function in the chloroplast using diagrams and electron micrographs

b) explain how the anatomy and physiology of the leaves of C4 plants, such as maize or sorghum, are adapted for high rates of carbon fixation at high temperatures in terms of:

• the spatial separation of initial carbon fixation from the light dependent stage (biochemical details of the C4 pathway are required in outline only)
• the high optimum temperatures of the enzymes involved

#85 Energy and Respiration - Syllabus 2016 - 2018

shahid Mandokhail A2 , Energy and Respiration

12.1 Energy

12.2 Respiration

Energy is a fundamental concept in biology. All living things require a source of cellular energy to drive their various activities. ATP is the universal energy currency as its molecules are small, soluble and easily hydrolysed to release energy for cellular activities. All organisms respire to release energy from energy- rich molecules such as glucose and fatty acids and transfer that energy to ATP. Respiration is a series of enzyme-catalysed reactions that release energy in small ‘packets’. In eukaryotes, aerobic respiration occurs in mitochondria.

Learning outcomes

Candidates should be able to:

12.1 Energy

ATP is the universal energy currency as it provides the immediate source of energy for cellular processes.

a) outline the need for energy in living organisms, as illustrated by anabolic reactions, such as DNA replication and protein synthesis, active transport, movement and the maintenance of body temperature

b) describe the features of ATP that make it suitable as the universal energy currency

c) explain that ATP is synthesised in substrate-linked reactions in glycolysis and in the Krebs cycle

d) outline the roles of the coenzymes NAD, FAD and coenzyme A in respiration

e) explain that the synthesis of ATP is associated with the electron transport chain on the membranes of mitochondria and chloroplasts (see 12.2g)

f) explain the relative energy values of carbohydrate, lipid and protein as respiratory substrates and explain why lipids are particularly energy-rich
g) define the term respiratory quotient (RQ) and determine RQs from equations for respiration

h) carry out investigations, using simple respirometers, to determine the RQ of germinating seeds or small invertebrates (e.g. blowfly larvae)

12.2 Respiration

Respiration is the process whereby energy from complex organic molecules is transferred to ATP.

This process of ATP synthesis using the energy in proton gradients is common to both respiration and photosynthesis.

Some organisms and some tissues are able to respire in both aerobic and anaerobic conditions. When yeast and plants respire under anaerobic conditions, they produce ethanol and carbon dioxide
as end-products; mammalian muscle tissue produces lactate when oxygen is in short
supply.

a) list the four stages in aerobic respiration (glycolysis, link reaction, Krebs cycle and oxidative phosphorylation) and state where each occurs in eukaryotic cells

b) outline glycolysis as phosphorylation of glucose and the subsequent splitting of fructose 1,6-bisphosphate (6C) into two triose phosphate molecules, which are then further oxidised to pyruvate with a small yield of ATP and reduced NAD

c) explain that, when oxygen is available, pyruvate is converted into acetyl (2C) coenzyme A in the link reaction

d) outline the Krebs cycle, explaining that oxaloacetate (a 4C compound) acts as an acceptor of the 2C fragment from acetyl coenzyme A to form citrate (a 6C compound), which is reconverted to oxaloacetate in a series of small steps

e) explain that reactions in the Krebs cycle involve decarboxylation and dehydrogenation and the reduction of NAD and FAD

f) outline the process of oxidative phosphorylation including the role of oxygen as the final electron acceptor (no details of the carriers are required)

g) explain that during oxidative phosphorylation:
• energetic electrons release energy as they pass through the electron transport system
• the released energy is used to transfer protons across the inner mitochondrial membrane
• protons return to the mitochondrial matrix by facilitated diffusion through ATP synthase providing energy for ATP synthesis (details of ATP synthase are not required)

h) carry out investigations to determine the effect of factors such as temperature and substrate concentration on the rate of respiration of yeast using a redox indicator (e.g. DCPIP or methylene blue)

i) describe the relationship between structure and function of the mitochondrion using diagrams and electron micrographs

j) distinguish between respiration in aerobic and anaerobic conditions in mammalian tissue and in yeast cells, contrasting the relative energy released by each (a detailed account of the total yield of ATP from the aerobic respiration of glucose is not required)

k) explain the production of a small yield of ATP from respiration in anaerobic conditions in yeast and in mammalian muscle tissue, including the concept of oxygen debt

l) explain how rice is adapted to grow with its roots submerged in water in terms of tolerance to ethanol from respiration in anaerobic conditions and the presence of aerenchyma

m) carry out investigations, using simple respirometers, to measure the effect of temperature on the respiration rate of germinating seeds or small invertebrates

#64.1 Ecology Syllabus 2015

shahid Mandokhail AS , Ecology

• Levels of ecological organisation
• Energy flow through ecosystems
• Recycling of nitrogen

Learning Outcomes

Candidates should be able to:

(a) define the terms habitat, niche, population, community and ecosystem and be able to recognise
examples of each ;

(b) explain the terms autotroph, heterotroph, producer, consumer and trophic level in the context of food chains and food webs ;

(c) explain how energy losses occur along food chains and discuss the efficiency of energy transfer
between trophic levels;

(d) describe how nitrogen is cycled within an ecosystem, including the roles of nitrogen-fixing bacteria (e.g. Rhizobium) and nitrifying bacteria (Nitrosomonas and Nitrobacter);

(e) use the knowledge gained in this section in new situations or to solve related problems.
Note: An ecosystem should be studied in relation to an area familiar to the candidates.

#57.2 Immunity - Syllabus 2016 - 2018

shahid Mandokhail AS , Immunity

11.1 The immune system
11.2 Antibodies and vaccination

An understanding of the immune system shows how cells and molecules function together to protect the body against infectious diseases and how the body is protected from further infection by the same pathogen. Phagocytosis is a more immediate non-specific part of the immune system, while the actions of lymphocytes provide effective defence against specific pathogens.

Learning outcomes

Candidates should be able to:

11.1 The immune system

The immune system has non-specific and specific responses to pathogens.

Auto-immune diseases are the result of failures in the system to distinguish between self

and non-self.

a) state that phagocytes (macrophages and neutrophils) have their origin in bone marrow and describe their mode of action

b) describe the modes of action of B-lymphocytes and T-lymphocytes

c) describe and explain the significance of the increase in white blood cell count in humans with infectious diseases and leukaemias

d) explain the meaning of the term immune response, making reference to the terms antigen, self and non-self

e) explain the role of memory cells in long-term immunity

f) explain, with reference to myasthenia gravis, that the immune system sometimes fails to distinguish between self and non- self

11.2 Antibodies and vaccination

Active and passive immunisations are effective ways to treat and prevent infectious diseases. Smallpox has been eradicated; other diseases may soon follow, but vaccine development

has proved more difficult for diseases such as malaria.

a) relate the molecular structure of antibodies to their functions (see 2.3b)

b) outline the hybridoma method for the production of monoclonal antibodies

c) outline the use of monoclonal antibodies in the diagnosis of disease and in the treatment of disease

d) distinguish between active and passive, natural and artificial immunity and explain how vaccination can control disease

e) discuss the reasons why vaccination programmes have eradicated smallpox, but not measles, tuberculosis (TB), malaria or cholera

#57 Immunity - Syllabus 2015

shahid Mandokhail AS , Immunity

• The immune system
• Vaccination

Candidates should be able to:

(a) [PA] recognise phagocytes and lymphocytes under the light microscope;

(b) state the origin and describe the mode of action of phagocytes (macrophages and neutrophils);

(c) describe the modes of action of B-lymphocytes and T-lymphocytes;

(d) explain the meaning of the term immune response, making reference to the terms antigen, self and non-self;

(e) explain the role of memory cells in long-term immunity;

(f) relate the molecular structure of antibodies to their functions;

(g) distinguish between active and passive, natural and artificial immunity and explain how vaccination can control disease ;

(h) discuss the reasons why vaccination programmes have eradicated smallpox but not measles,
tuberculosis (TB), malaria or cholera;

# 54.2 Infectious disease - Syllabus 2016 - 2018

shahid Mandokhail AS , Infectious diseases

10.1 Infectious diseases
10.2 Antibiotics

The infectious diseases studied in this section are caused by pathogens that are transmitted from one human host to another. Some, like Plasmodium that causes malaria, are transmitted by vectors; others are transmitted through water and food or during sexual activity. An understanding of the biology of the pathogen and its mode of transmission is essential if the disease is to be controlled and ultimately prevented.

Learning outcomes

Candidates should be able to:

10.1 Infectious diseases

While many infectious diseases have been successfully controlled in some parts of the world, many people worldwide are still at risk of these diseases.

a) define the term disease and explain the difference between an infectious disease and a non-infectious disease (limited to sickle cell anaemia and lung cancer)

b) state the name and type of causative organism (pathogen) of each of the following diseases: cholera, malaria, tuberculosis (TB), HIV/AIDS, smallpox and measles (detailed knowledge of structure is not required. For smallpox (Variola) and measles (Morbillivirus) only the name of genus is needed)

c) explain how cholera, measles, malaria, TB and HIV/AIDS are transmitted

d) discuss the biological, social and economic factors that need to be considered in the prevention and control of cholera, measles, malaria, TB and HIV/AIDS (a detailed study of the life cycle of the malarial parasite is not required)

e) discuss the factors that influence the global patterns of distribution of malaria, TB and HIV/AIDS and assess the importance of these diseases worldwide

10.2 Antibiotics

The ‘age of antibiotics’ began in the 1940s with the availability of penicillin. With an increase in antibiotic resistance is this age about to come to an end?

a) outline how penicillin acts on bacteria and why antibiotics do not affect viruses

b) explain in outline how bacteria become resistant to antibiotics with reference to mutation and selection

c) discuss the consequences of antibiotic resistance and the steps that can be taken to reduce its impact

# 54.1 Infectious disease - Syllabus 2015

shahid Mandokhail AS , Infectious diseases

• Cholera, malaria, tuberculosis (TB), HIV/AIDS, smallpox and measles
• Antibiotics

Learning Outcomes

Candidates should be able to:

(a) define the term disease and explain the difference between an infectious disease and
non-infectious diseases;

(b) state names and types of causative organism of each of the following diseases: cholera, malaria, TB, HIV/AIDS, smallpox and measles (detailed knowledge of structure is not required. For smallpox (Variola) and measles (Morbillivirus) names of genus only is needed);

(c) explain how cholera, measles, malaria, TB and HIV/AIDS are transmitted;

(d) discuss the factors that need to be considered in the prevention and control of cholera, measles, malaria, TB and HIV/AIDS (a detailed study of the life cycle of the malarial parasite is not required) (an appreciation of social and biological factors and how economic factors can affect these should be included);

(e) discuss the factors that influence the global patterns of distribution of malaria, TB and HIV/AIDS and assess the importance of these diseases worldwide;

(f) outline the role of antibiotics in the treatment of bacterial infectious diseases (knowledge of specific antibiotics and their mode of action is not required);

(g) use the knowledge gained in this section in new situations or to solve related problems.

#49.2 Gas exchange And Smoking Syllabus 2016 - 2018

shahid Mandokhail AS , Gas exchange

9.1 The gas exchange system
9.2 Smoking

The gas exchange system is responsible for the uptake of oxygen into the blood and excreting carbon dioxide. An understanding of this system shows how cells, tissues and organs function together to exchange these gases between the blood and the environment. The health of this system and of the cardiovascular system is put at risk by smoking.

Learning outcomes

Candidates should be able to:

9.1 The gas exchange system

The gas exchange surface in the lungs is extensive, very thin, well supplied with blood and well ventilated. The trachea and bronchi provide little resistance to the movement of air to and from the alveoli.

a) describe the gross structure of the human gas exchange system

b) observe and draw plan diagrams of the structure of the walls of the trachea, bronchi, bronchioles and alveoli indicating the distribution of cartilage, ciliated epithelium, goblet cells, smooth muscle, squamous epithelium and blood vessels

c) describe the functions of cartilage, cilia, goblet cells, mucous glands, smooth muscle and elastic fibres and recognise these cells and tissues in prepared slides, photomicrographs and electron micrographs of the gas exchange system

d) describe the process of gas exchange between air in the alveoli and the blood

9.2 Smoking

Smoking is one of the major avoidable risk factors of chronic, life-threatening diseases of the gas exchange and circulatory systems.

a) describe the effects of tar and carcinogens in tobacco smoke on the gas exchange system with reference to lung cancer and chronic obstructive pulmonary disease (COPD)

b) describe the short-term effects of nicotine and carbon monoxide on the cardiovascular system

#49.1 Gas exchange And Smoking Syllabus 2015

shahid Mandokhail AS , Gas exchange

• The gas exchange system
• Smoking and smoking-related diseases

Learning Outcomes

Candidates should be able to:

(a) [PA] describe the structure of the human gas exchange system, including the microscopic structure of the walls of the trachea, bronchioles and alveoli with their associated blood vessels;

(b) [PA] describe the distribution of cartilage, ciliated epithelium, goblet cells and smooth muscle in the trachea, bronchi and bronchioles;

(c) describe the functions of cartilage, cilia, goblet cells, mucous glands, smooth muscle and elastic fibres in the gas exchange system;

(d) describe the process of gas exchange between air in the alveoli and the blood;

(e) describe the effects of tar and carcinogens in tobacco smoke on the gas exchange system;

(f) describe the signs and symptoms that enable diagnosis of lung cancer and chronic obstructive
pulmonary disease (COPD) (emphysema and chronic bronchitis);

(g) describe the effects of nicotine and carbon monoxide on the cardiovascular system;

(h) explain how tobacco smoking contributes to atherosclerosis and coronary heart disease (CHD);

(i) evaluate the epidemiological and experimental evidence linking cigarette smoking to disease and early death;

(j) discuss the difficulties in achieving a balance between preventions and cure with reference to coronary heart disease, coronary by-pass surgery and heart transplant surgery;

(k) use the knowledge gained in this section in new situations or to solve related problems.

#43.2 Transport in mammals - Syllabus 2016 - 2018

shahid Mandokhail AS , Syllabus

8.1 The circulatory system
8.2 The heart

As animals become larger, more complex and more active, transport systems become essential to supply nutrients to, and remove waste from, individual cells. Mammals are far more active than plants and require much greater supplies of oxygen. This is transported by haemoglobin inside red blood cells. Candidates will be expected to use the knowledge gained in this section to solve problems in familiar and unfamiliar contexts.

Learning outcomes

Candidates should be able to:

8.1 The circulatory system

The mammalian circulatory system consists of a pump, many blood vessels and blood, which is a suspension of red blood cells and white blood cells in plasma.

a) state that the mammalian circulatory system is a closed double circulation consisting of a heart, blood vessels and blood

b) observe and make plan diagrams of the structure of arteries, veins and capillaries using prepared slides and be able to recognise these vessels using the light microscope

c) explain the relationship between the structure and function of arteries, veins and capillaries

d) observe and draw the structure of red blood cells, monocytes, neutrophils and lymphocytes using prepared slides and photomicrographs

e) state and explain the differences between blood, tissue fluid and lymph

f) describe the role of haemoglobin in carrying oxygen and carbon dioxide with reference to the role of carbonic anhydrase, the formation of haemoglobinic acid and carbaminohaemoglobin (details of the chloride shift are not required)

g) describe and explain the significance of the oxygen dissociation curves of adult oxyhaemoglobin at different carbon dioxide concentrations (the Bohr effect)

h) describe and explain the significance of the increase in the red blood cell count of humans at high altitude

8.2 The heart

The mammalian heart is a double pump: the right side pumps blood at low pressure to the lungs and the left side pumps blood at high pressure to the rest of the body.

a) describe the external and internal structure of the mammalian heart

b) explain the differences in the thickness of the walls of the different chambers in terms of their functions with reference to resistance to flow

c) describe the cardiac cycle (including blood pressure changes during systole and diastole)

d) explain how heart action is initiated and controlled (reference should be made to the sinoatrial node, the atrioventricular node and the Purkyne tissue, but not to nervous and hormonal control)

#43.1 Transport in mammals - Syllabus 2015

shahid Mandokhail AS , Syllabus

• The need for, and functioning of, a transport system in mammals
• Structure and functioning of the mammalian heart

Learning Outcomes

Candidates should be able to:

(m) [PA] describe the structures of arteries, veins and capillaries and be able to recognise these vessels using the light microscope;

(n) explain the relationship between the structure and function of arteries, veins and capillaries;

(o) [PA] describe the structure of red blood cells, phagocytes (macrophages and neutrophils) and
lymphocytes;

(p) state and explain the differences between blood, tissue fluid and lymph;

(q) describe the role of haemoglobin in carrying oxygen and carbon dioxide (including the role of carbonic anhydrase, the formation of haemoglobinic acid and carbaminohaemoglobin);

(r) describe and explain the significance of the oxygen dissociation curves of adult oxyhaemoglobin at different carbon dioxide concentrations (the Bohr effect);

(s) describe and explain the significance of the increase in the red blood cell count of humans at high
altitude;

(t) describe the external and internal structure of the mammalian heart;

(u) explain the differences in the thickness of the walls of the different chambers in terms of their functions;

(v) describe the mammalian circulatory system as a closed double circulation;

(w) describe the cardiac cycle (including blood pressure changes during systole and diastole);

(x) explain how heart action is initiated and controlled (reference should be made to the sinoatrial node, the atrioventricular node and the Purkyne tissue);

(y) use the knowledge gained in this section in new situations or to solve related problems.

#38.2 Transport in multicellular plants - Syllabus 2016 - 2018

shahid Mandokhail AS , Syllabus

7.1 Structure of transport tissues
7.2 Transport mechanisms

Flowering plants do not have compact bodies like those of animals. Leaves and extensive root systems spread out to obtain the light energy, water, mineral ions and carbon dioxide that plants gain from their environment to make organic molecules, such as sugars and amino acids. Transport systems in plants move substances from where they are absorbed or produced to where they are stored or used. Plants do not have systems for transporting oxygen and carbon dioxide; instead these gases diffuse through air spaces within stems, roots and leaves.

Learning Outcomes

Candidates should be able to:

7.1 Structure of transport tissues

Plants have two transport tissues: xylem and phloem.

a) draw and label from prepared slides plan diagrams of transverse sections of stems, roots and leaves of herbaceous dicotyledonous plants using an eyepiece graticule to show tissues in correct proportions (see 1.1c)

b) draw and label from prepared slides the cells in the different tissues in roots, stems and leaves of herbaceous dicotyledonous plants using transverse and longitudinal sections

c) draw and label from prepared slides the structure of xylem vessel elements, phloem sieve tube elements and companion cells and be able to recognise these using the light microscope

d) relate the structure of xylem vessel elements, phloem sieve tube elements and companion cells to their functions

7.2 Transport mechanisms

Movement of xylem sap and phloem sap is by mass flow. Movement in the xylem is passive as it is driven by evaporation from the leaves; plants use energy to move substances in the phloem.
Xylem sap moves in one direction from the roots to the rest of the plant. The phloem sap in a phloem sieve tube moves in one direction from the location where it is made to the location where it is used or stored. At any one time phloem sap can be moving in different directions in different sieve tubes.

a) explain the movement of water between plant cells, and between them and their environment, in terms of water potential (see 4.2. No calculations involving water potential will be set)

b) explain how hydrogen bonding of water molecules is involved with movement in the xylem by cohesion-tension in transpiration pull and adhesion to cellulose cell walls

c) describe the pathways and explain the mechanisms by which water and mineral ions are transported from soil to xylem and from roots to leaves (include reference to the symplastic pathway and apoplastic pathway and Casparian strip)

d) define the term transpiration and explain that it is an inevitable consequence of gas exchange in plants

e) investigate experimentally and explain the factors that affect transpiration rate using simple potometers, leaf impressions, epidermal peels, and grids for determining surface area

f) make annotated drawings, using prepared slides of cross-sections, to show how leaves of xerophytic plants are adapted to reduce water loss by transpiration

g) state that assimilates, such as sucrose and amino acids, move between sources (e.g. leaves and storage organs) and sinks (e.g. buds, flowers, fruits, roots and storage organs) in phloem sieve tubes

h) explain how sucrose is loaded into phloem sieve tubes by companion cells using proton pumping and the co-transporter mechanism in their cell surface membranes

i) explain mass flow in phloem sap down a hydrostatic pressure gradient from source to sink

#38.1 Transport in multicellular plants - Syllabus 2015

shahid Mandokhail AS , Syllabus

• The need for, and functioning of, a transport system in multicellular plants

Learning Outcomes

Candidates should be able to:

(a) explain the need for transport systems in multicellular plants and animals in terms of size and surface area to volume ratios;

(b) define the term transpiration (see section 5) and explain that it is an inevitable consequence of gas
exchange in plants;

(c) [PA] describe how to investigate experimentally the factors that affect transpiration rate;

(d) [PA] describe the distribution of xylem and phloem tissue in roots, stems and leaves of dicotyledonous plants;

(e) [PA] describe the structure of xylem vessel elements, phloem sieve tube elements and companion cells and be able to recognise these using the light microscope;

(f) relate the structure of xylem vessel elements, phloem sieve tube elements and companion cells to their functions;

(g) explain the movement of water between plant cells, and between them and their environment, in terms of water potential (no calculations involving water potential will be set);

(h) describe the pathways and explain the mechanisms by which water is transported from soil to xylem and from roots to leaves (includes reference to the symplast/symplastic pathway and apoplast/apoplastic pathway);

(i) outline the roles of nitrate ions and of magnesium ions in plants;

(j) [PA] describe how the leaves of xerophytic plants are adapted to reduce water loss by transpiration;

(k) explain translocation as an energy-requiring process transporting assimilates, especially sucrose,
between the leaves (sources) and other parts of the plant (sinks);

(l) explain the translocation of sucrose using the mass flow hypothesis;

# 33.2 Nucleic acids and protein synthesis - Syllabus 2016 - 2018

shahid Mandokhail AS , Genetic control

6.1 Structure and replication of DNA
6.2 Protein synthesis

Nucleic acids have roles in the storage and retrieval of genetic information and in the use of this
information to synthesise polypeptides. DNA is an extremely stable molecule that cells replicate with
extreme accuracy. The genetic code is used by cells for assembling amino acids in correct sequences to make polypeptides. In eukaryotes this involves the processes of transcription in the nucleus to produce short-lived molecules of messenger RNA followed by translation in the cytoplasm.

Learning Outcomes
Candidates should be able to:

6.1 Structure and replication of DNA

Understanding the structure of nucleic acids allows an understanding of their role in the storage of genetic information and how that information is used in the synthesis of proteins.

a) describe the structure of nucleotides, including the phosphorylated nucleotide ATP (structural formulae are not required)

b) describe the structure of RNA and DNA and explain the importance of base pairing and the different hydrogen bonding between bases (include reference to adenine and guanine as purines and to cytosine, thymine and uracil as pyrimidines. Structural formulae for bases are not required but the recognition that purines have a double ring structure and pyrimidines have a single ring structure should be included)
c) describe the semi-conservative replication of DNA during interphase

6.2 Protein synthesis

The genetic code specifies the amino acids that are assembled to make polypeptides. The way that
DNA codes for polypeptides is central to our understanding of how cells and organisms function.

a) state that a polypeptide is coded for by a gene and that a gene is a sequence of nucleotides that forms part of a DNA molecule

b) state that a gene mutation is a change in the sequence of nucleotides that may result in an altered polypeptide

c) describe the way in which the nucleotide sequence codes for the amino acid sequence in a polypeptide with reference to the nucleotide sequence for HbA (normal) and HbS (sickle cell)
alleles of the gene for the β-globin polypeptide

d) describe how the information in DNA is used during transcription and translation to construct polypeptides, including the role of messenger RNA (mRNA), transfer RNA (tRNA) and the ribosomes

#155 Genetic technology Syllabus 2016 -2048

#144 Biodiversity, classification and conservation Syllabus 2016 - 2018

#137 Selection and Evolution Syllabus 2016 - 2018

#117 Control and co-ordination Syllabus 2016-2018

# 107 Homeostasis Syllabus 2016-2018

#98 Photosynthesis Syllabus 2016-2018

#85 Energy and Respiration - Syllabus 2016 - 2018

#64.1 Ecology Syllabus 2015

#57.2 Immunity - Syllabus 2016 - 2018

#57 Immunity - Syllabus 2015

# 54.2 Infectious disease - Syllabus 2016 - 2018

# 54.1 Infectious disease - Syllabus 2015

#49.2 Gas exchange And Smoking Syllabus 2016 - 2018

#49.1 Gas exchange And Smoking Syllabus 2015

#43.2 Transport in mammals - Syllabus 2016 - 2018

#43.1 Transport in mammals - Syllabus 2015

#38.2 Transport in multicellular plants - Syllabus 2016 - 2018

#38.1 Transport in multicellular plants - Syllabus 2015

# 33.2 Nucleic acids and protein synthesis - Syllabus 2016 - 2018

Featured

Popular

Popular Posts

Tags

Pages

Contact Form