Biology Flashcards
Define ‘genes’
A trait in a living organism.
Define ‘allele’
Versions of a gene.
Define ‘chromosome’
A structure that contains the genetic information in forms of genes.
Dominant vs Recessive
Dominant is the gene that is the strongest. Recessive is the weakest gene that usually doesn’t show up unless the geneotype is homozygous recessive.
Homozygous vs Heterozygous
Homozygous means two of the same genes. Heterozygous means two different genes.
Genotype vs Phenotype
Genotype is the genetic make-up of an organism, e.g ‘Bb’. Phenotype is the physical characteristics e.g ‘Blue eyes’.
What type of cell division is Mitosis?
Skin cell repairing/replacing.
What type of cell division is Meiosis?
Sex cell division.
How many chromosomes are in Meiosis?
23.
How many chromosomes are in Mitosis?
46.
What is the purpose of Meiosis?
Gamete production.
What is the purpose of Mitosis?
Cell repairing/replacing.
Which cell division has unique cells?
Meiosis.
Which cell division has identical cells?
Mitosis.
Define ‘haploid’
A single set of chromosomes in a cell, half from each parent.
Define ‘diploid’
2 sets of chromosomes, one from each parent.
Define ‘discontinuous variation’
When there is a limited number of possible variations, e.g eye colour.
Define ‘continuous variation’
When the variations there is not a limited amount of possible variations, e.g height.
Define ‘zygote’
The fertilised egg & combined sperm before it becomes a foetus.
Define ‘gamete’
The male or female sex cell, e.g egg or sperm.
Define ‘gametic mutation’
A change in either the gene/genotype or the DNA sequence
Define ‘shuffling/crossover’
Happens only in meiosis, combinations of alleles which creates the unique offspring.
