3.Genetics Flashcards
How many daughter cells are produced in a meiotic cell division?
4
How many chromosomes do daughter produce in meiosis have compared to normal cells?
Half as many
Describe the daughter cells produced in meiosis
Genetically different haploid gametes
What is the structure of DNA?
Double helix
What links the strands together in the DNA
Complementary base pairs
What holds the base pairs together in DNA
Weak hydrogen bonds
What is a genome?
The entire DNA of an organism
What is a gene
A section of DNA molecule
What do genes do?
Code for a specific protein
Why are there different in inherited characteristics?
Coz of alleles
What does chromosome mean?
A thread like structure found in the nucleus of souls. Each chromosome contains one enormously long DNA molecule packed with proteins
What does allele mean?
A different version of a gene
What does dominant mean?
An allele that will always affect phenotype
What does recessive mean?
An allele that will only affect a phenotype if the other allele present is also recessive
What does homozygous mean?
One both alleles of a gene are different in an organism
What does heterozygous mean?
When both the alleles for a gene are different in an organism
What does genotype mean?
The alleles for a certain characteristic that are found in a organism
What does phenotype mean?
A characteristic that are produced by a certain set of alleles
What does gamete mean?
A haploid cell produced by meiosis used for sexual reproduction
What does zygote mean?
A fertilised egg cell
What is genetic variation?
Different characteristics as a result of mutation and asexual reproduction
What is environmental variation?
Different characteristics caused by an organisms environment
Why is there usually extensive genetic variation within a population of a species?
Mutations
