What is a chromosome?
Genes that contains genetic information and is made of DNA.
What is a gene?
A length of DNA that codes for a protein.
Define allele.
An alternative form of a gene
Describe the inheritance of sex in humans.
XY chromosomes is male chromosomes
XX chromosomes is female chromosomes
Describe a haploid nucleus.
A nucleus containing a single set of chromosomes.
Describe a diploid nucleus.
A nucleus containing two sets of chromosomes.
Describe mitosis.
Nuclear division giving rise to genetically identical cells (details of the stages of mitosis are NOT required).
What is in a diploid cell?
A pair of each type of chromosome and in a human diploid cell there are 23 pairs
What is the role of mitosis?
Growth, repair of damaged tissues, replacement of cells and asexual production.
What happens during mitosis?
Copies of chromosomes separate, maintaining the chromosome number in each daughter cell.
What is meiosis involved in?
Production of gametes.
Describe meiosis.
A reduction division in which the chromosome number is halved from diploid to haploid resulting in genetically different cells (details of the stages of meiosis are NOT required).
Describe inheritance.
Transmission of genetic information from generation to generation.
Describe genotype.
Genetic make-up of an organism and in terms of the alleles present.
Describe phenotypes.
Observable features of an organism.
Describe homozygous.
Having 2 identical alleles of a particular gene.
When homozygous individuals breed together, what is it called?
Pure-breeding
