End Of Unit Questions Flashcards
How many chromosomes does a human have in each body cell?
23 pairs (or 46 individual)
Which type of cell division produces sex cells?
Meiosis
What molecules are genes made of?
DNA
What are alleles?
Different forms of one gene
Why does sexual reproduction result in variation?
The genetic material from two parents is brought together when the sperm and egg nuclei fuse
Explain why offspring produced in asexual reproduction are genetically identical
They are produced by mitosis, cells from one parents divide to form the offspring (identical to parent)
What is meant by the term genotype?
The genes present in a cell (allele combination)
What do we mean by a heterozygous individual?
The individual has one dominant and one recessive allele for a condition
What are the chance of a child having polydactyly if one parent is heterozygous and the other is homozygous recessive?
50%
Why do cells divide by mitosis?
To produce identical cells for growth and to replace cells
