B3 GENETICS Flashcards
gametes
egg and sperm cell
fertilisation
sperm cell fuses with egg cell and nuclei combine
zygote
single cell formed by fertilisation
gene
length of DNA coding for a protein
controls your characteristics
genome
all the DNA and genes in an organism
protein
polymer made from amino acids
polymer
long molecule made by chaining together many shorter ones
diploid
a cell with 23 pairs of chromosomes (46 in total)
haploid
a cell with 23 single chromosomes
meiosis
cell division that makes gametes
meiosis stages
DNA replicates cell divides into 2 diploid cells, these divide into 4 haploid daughters
why gametes are different
chromosomes in a pair are slightly different. Different gametes get different combinations of chromosomes
Chromosome
large DNA molecule made into a small package by tightly coiling DNA around a protein
DNA structure
two strands , double helix , complementary base pairs , sugar-phosphate backbone
DNA bases
adenine A thymine T
cystosine C guanine G
complementary base pairs
A pairs with T
C pairs with G
hydrogen bonds
weak force holding the two strands of DNA together
DNA analysis
issues small differences in DNA to determine family relationships or link people to crimes