Genetic Diversity via Mutation ( Genetic Diversity And Adaptation ) Flashcards
The figure below summarises the process of meiosis.
The circles represent cells and the
structures within each cell represent chromosomes.
( Image shows a cell undergoing different stages of meiosis in separate images, labelled Cell X, division 1 and division 2 )
Describe and explain the appearance of one of the chromosomes in cell X.
- Chromosome is formed of two chromatids
- due to DNA replication
- Chromatids are held together by a centromere
Describe what has happened during division 1 in the figure above.
- Chromosomes are in homologous pair
- One of each into daughter cells
Identify one event that occurred during division 2 but not during division 1.
- Separation of chromatids
Name two ways in which meiosis produces genetic variation.
- Independent segregation
- Crossing over
The diagram below represents one process that occurs during protein synthesis.
( Image shows a tRNA molecule and an mRNA molecule )
- Translation
Identify the molecule labelled Q.
- transfer tRNA
In the diagram above, the first codon is AUG. Give the base sequence of:
the complementary DNA base sequence
- TAC
the missing anticodon
- UAC
The table below shows the base triplets that code for two amino acids.
Amino acid
1 ) Aspartic acid
2 ) Proline
Encoding base triplet
1 ) GAC, GAU
2 ) CCA, CCG, CCC, CCU
Aspartic acid and proline are both amino acids.
Describe how two amino acids differ
from one another.
You may use a diagram to help your description.
- Have different R groups
Deletion of the sixth base (G) in the sequence shown in the diagram above would change the nature of the protein produced but substitution of the same base would
not.
Use the information in the table and your own knowledge to explain why.
- Substitution would result in CCC
- All code for same amino acid
- Deletion would cause frame shift
