Download CfE Higher Human Biology Unit 1 Human Cells

CfE Higher Human Biology
Unit 1 Human Cells
Learning Outcomes/Success Criteria Unit 1 CfE Higher Human Biology
I can describe that stem cells are unspecialised cells that can divide and can
differentiate into specialised cells.
I can identify both embryonic and adult (tissue) stem cells as types of stem
cell, and name the types of cell that they can produce.
I can give examples of how stem cells are being used e.g. in bone marrow
transplants, skin grafts, cornea transplants and as model ells in drug testing.
I can identify the moral and ethical considerations when using stem cells.
I can explain how specialised cells arise through the process of differentiation
and gene expression.
I can give examples of somatic cells and differentiated tissues in humans.
I can identify the numbers of chromosomes present in somatic cells, germline
cells and gametes, and how chromosome number is maintained during mitosis,
but halved in meiosis.
I can describe cancer as cells which continuously divide and can explain how
secondary tumours form.
I can state that the genotype of an organism depends on the sequence of bases
on DNA, which is found in genes, on chromosomes, together with any associated
proteins.
I can describe the structure and replication of DNA, including its antiparallel
nature, bonding and base pairs
I can state that several molecules are required for DNA replication, including
DNA polymerase, primers, DNA ligase
I can state that nucleotides are added to the 3’ end of DNA.
I can explain that during DNA replication, the leading strand continuously
synthesises a new DNA strand, where in the lagging strand, DNA is synthesised
in segments, and joined by DNA ligase.
I can describe the sequence of events that occurs during synthesis of mRNA in
the nucleus, and state the main differences between DNA and RNA.
I can state that proteins are produced by the processes of transcription and
translation, including formation of the primary transcript, and that completed
proteins are produced from amino acids in ribosomes in the cytoplasm, which
are linked by peptide bonds.
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CfE Higher Human Biology
Unit 1 Human Cells
I can state that ribosomes are formed from proteins and mRNA.
I can explain how amino acids are produced from the base sequence in DNA to
codons in mRNA to anticodons in tRNA and that each tRNA molecule carries a
specific amino acid.
I can state that several molecules are required for protein synthesis, including
RNA polymerase, promoters and terminators.
I can state that introns are non-coding regions of genes and exons are coding
regions of genes.
I can explain how introns from the primary transcript of mRNA are removed in
RNA splicing.
I can describe how a variety of proteins can be expressed from the same gene
as a result of alternative RNA splicing and post-translational modification.
I can explain that in post translation modification, protein structure is
modified by cutting and combining polypeptide chains or by adding phosphate or
carbohydrate groups to the protein.
I can describe how polypeptides are formed due to its 3D shape, hydrogen
bonds and other interactions between amino acids, and give examples of types
of proteins produced.
I can state that genetic disorders are caused by changes to genes or
chromosomes that result in the proteins not being expressed or the proteins
expressed not functioning correctly.
I can identify single gene mutations and give suitable examples, including
missense, nonsense, splice site and nucleotide sequence repeat expansion
mutations.
I can identify chromosome mutations and give suitable examples including
deletion, duplication and translocation.
I can state that computer technology can be used to identify known gene
sequences (bioinformatics), identify relationships between species
(systematics) and to allow personalised medicine and pharmacogentics.
I can state that PCR allows amplification of DNA through cycles of heating to
separate the strands, then cooling to allow primers to bind to target DNA
sequences, and that heat tolerant DNA polymerase is used in this process
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CfE Higher Human Biology
Unit 1 Human Cells
I can explain how DNA probes with fluorescent labels are used in identifying
disease and in showing relationships between individuals e.g. paternity testing,
and this can be carried out multiple times with microarrays.
I can describe the difference between anabolic and catabolic processes, and
explain how metabolic pathways can have reversible and irreversible steps as
well as alternative pathways.
I can state that metabolic pathways are controlled at each step by enzymes,
and can also be controlled by intracellular and extracellular signalling molecules.
I can state that enzymes have active sites with affinity for substrate
molecules, and then when the two combine, induced fit occurs.
I can explain how when enzymes and substrates combine, the reactants are
orientated to the active site, the activation energy is lowered and the products
are then released from the active site.
I can describe the effect of substrate concentration and end product
concentration on the rate of the reaction, and give examples.
I can describe the differences between competitive and non-competitive
inhibitors, and explain how feedback inhibition can control the rate of reaction
in a metabolic pathway.
I can identify ATP as the high energy compound which transfers energy, and is
produced when ADP combines with phosphate in phosphorylation, building up
energy, and releases energy when broken down into ADP and phosphate once
more.
I can state that cells use high energy electrons to pump hydrogen ions across a
membrane, which activates the enzyme ATP synthase, and helps to produce
ATP.
I can describe the process of glycolysis including the energy investment stage
and the energy pay off phase, and the use of phosphofructokinase in
progressing the glycolysis pathway.
I can describe the sequence of events that occur after pyruvate production,
and onto the citric acid cycle, in the presence of oxygen including the
production of acetyl coenzyme A, citric acid and oxaloacetate.
I can state the number of carbon atoms present in each of the main carbon
compounds in respiration, and the use of dehydrogenase enzymes to remove
hydrogen ions which are then passed to the coenzyme molecules FAD and NAD.
I can describe NAD and FAD as carrier molecules, which carry the high energy
electrons to the electron transport chain.
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CfE Higher Human Biology
Unit 1 Human Cells
I can explain how the high energy electrons release energy, which is then used
to pump hydrogen ions across the membrane, activating ATP synthase and
producing ATP.
I can state that oxygen is the final hydrogen acceptor in the electron
transport chain, and combines with hydrogen to produce water.
I can explain how creatine phosphate can break down, releasing phosphate and
allowing the production of ATP from ADP and phosphate during strenuous
activity.
I can describe how ATP production can be regulated by the build-up of ATP or
citric acid as these can inhibit phosphofructokinase.
I can identify starch and glycogen as alternative respiratory substrates, as well
as proteins and fats.
I can state that alternative respiratory substrates can be converted to
intermediate molecules in glycolysis, and can then enter the citric acid cycle.
I can describe the conversion of pyruvate to lactic acid during strenuous activity when
insufficient oxygen is available, and the build-up of an oxygen debt, which must be repaid
when the activity is over.
I can identify the two types of muscle fibre, and the differences in their number of
mitochondria, blood supply, storage fuel and rate of contraction and give examples of the
type of activities which depend on them.
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