1.9 genetic variation
Achievement
Demonstrate
understanding of biological ideas relating to genetic variation. This involves
recognising, naming, drawing, giving characteristics of, or an account of
genetic variation.
Make sure you can
describe:
- how DNA carries instructions
to the next generation
- the link between DNA and
phenotype
- the differences between a
chromosome, DNA and a gene
- the relationship between
genes and alleles
- the link between genotype and
phenotype
- how chromosomes exist in
pairs
- how individuals inherit two
copies of most genes
- the importance of having
different alleles of a gene
- how mutations form new
alleles
- how meiosis produces gametes
- how sexual reproduction
produces genetic variation between individuals within a group of living
organisms
- the possible genotypes, and
phenotype ratios of a simple monohybrid cross showing complete dominance
- the possible genotypes, and
phenotype ratios of a simple monohybrid cross showing sex determination
- outcomes of a simple
monohybrid cross using a Punnett square
- genotype and phenotype
outcomes of a simple monohybrid cross shown in a pedigree chart
- inheritable variation that
exists within a group of living things
- non-inheritable variation
that exists within a group of living things
- how variation in phenotype
within a group of living things gives differing rate of survival
- the advantages and
disadvantages of sexual reproduction
- describe the specialised
terms outlined in the subject content.
Achievement with Merit
Demonstrate in-depth
understanding of biological ideas relating to genetic variation. This involves
explaining how or why genetic variation occurs.
Make sure you can
explain:
- the importance of DNA as the
molecule carrying instructions for life to the next generation
- how DNA determines phenotype
- the relationship between a
chromosome, DNA and a gene
- the importance of having
different alleles of a gene
- how genotype determines
phenotype
- why chromosomes exist in
pairs - one from each parent
- why individuals inherit two
copies of most genes - gives more genetic variation
- how alleles of a
gene differ – the order of bases in the DNA
- how changes in the DNA
(mutations) may or may not form a new alleles
- how meiosis produces gametes
with genetic variation
- how meiosis and fertilisation
produce genetic variation between parents and offspring
- the reasons for the possible
genotype, and phenotype ratio of a simple monohybrid cross showing
complete dominance
- the reasons for the possible
genotypes, and phenotype ratios of a simple monohybrid cross showing sex
determination
- how variation in phenotype
within a group of living things gives differing rate of survival
- how variation within a group
of living things is important in a changing environment such as pest
infestation, disease, drought or flood
- reasons for the advantages
and disadvantages of sexual reproduction
Achievement with Excellence
Demonstrate
comprehensive understanding of biological ideas relating to genetic variation.
This involves
linking biological ideas about genetic variation. It may involve explaining,
elaborating, applying, justifying, relating, evaluating, comparing and
contrasting, or analysing.
Make sure you can:
- describe and explain the
ideas listed above for achieved and merit
- use linking words and
phrases, such as ‘because’, ‘this means that’, ‘whereas. ‘however;’ when
comparing and contrasting, discussing, elaborating etc.
- show you understand that
probability outcomes indicated in Punnett squares are dependent on chance
and effected by sample sizes
- demonstrate an understanding
of chromosome numbers and genetic variation related to meiosis and sexual
reproduction.