[Unit 8.2] | DNA & Chromosomes Flashcards
1
Q
How are chromosomes structured?
A
• A DNA molecule wrap around histone molecules to form a DNA-histone complex.
• Complex is coiled, then further looped & coiled before being condensed into a chromosome.
• Each chromosome contains 1 very long DNA molecule.
2
Q
What are homologous pairs of chromosomes?
A
• Where 1 chromosome is derived from the mother’s chromosomes and 1 is derived from the father’s in each pair.
• They carry the same genes but not necessarily the same alleles.
3
Q
What is the diploid number?
A
The total number of chromosomes in the nucleus. (46 in humans.)
4
Q
What is an allele?
A
• An alternative form of a gene.
• They have different base sequences and therefore produce different polypeptides.
