What is sexual reproduction? (What material are chromosomes made from?…
What is sexual reproduction?
Sexual reproduction involves the joining (fusion) of male and female gametes
Describe Asexual reproduction
Asexual reproduction involves only one parent and no fusion of gametes. There is no mixing of genetic information. This leads to genetically identical offspring (clones). Only mitosis is involved
What are gametes?
Male or femalesex cells
How many chromosomes do gametes have?
How many chromosomes does a body cell have?
What is fertilisation
When the nucleus of the male and female gamates fuse together.
What material are chromosomes made from?
Define the term 'gene'
A gene is a small section of DNA on a chromosome.
Define the term 'allele'
Different forms of the same gene
Define the term 'homozygous'
When a pair of chromosomes have the same allele for aparticular trait
Define the term 'heterozygous'
When a pair of chromosomes have the different alleles for a particular trait
Name a disorder caused by a dominant allele
Polydactyly (having extra fingers or toes) is caused by a dominant allele
Name a disorder caused by a recessive allele
Cystic fibrosis (a disorder of cell membranes) is caused by a recessive allele. Students should make