biology t3 exam 2023 Flashcards
DNA
Deoxyribonucleic acid. Carries genetic information and can not leave the nucleus of a cell. The structure formed is called a double helix.
nucleotide
The building block of all nucleic acids, which include DNA and RNA.
nitrogenous base
a component of nucleotides.
complimentary base
strands that connect to eachother. for example, A&T, C&G.
Protein
a molecule made up of amino acids
Allele
variant of a gene
Homozygous
having two identical alleles of a particular gene or genes.
Heterozygous
having two different alleles of a particular gene or genes.
Phenotype
physical characteristic (what you look like)
Genotype
genetic makeup (what your genes are)
Dominant
Alleles are expressed in capital letters, eg TT or Tt, this is the gene which will be expressed no matter what it is paired with.
Reccessive
Alleles are expressed with lowercase letters, they represent the gene that will be less likely to occur. This gene will only occur if there are two lower case letters, eg tt
Eukaryotes
single celled organisms with a nucleus
Prokaryotes
single celled organsisms without a nucleus or other membrane bound organelles
Mitosis
Part of the cell cycle which replicated chromosomes are separated into 2 new nuclei
Gamete
reproductive cell sperm/egg
zygote
fertilised egg
haploid
a cell with only one set of two chromosomes
diploid
a cell with two sets of chromosomes (human cell)
centromere
central part of a chromosome
P arm
shortest arm of a chromosome
Q arm
longest arm of a chromosome
codon
a sequence of 3 nucleotides in a DNA/RNA molecule which code for an amino acid (eg, CAG, ACG)
mRNA
messenger RNA, a type of RNA polymerase using DNA as a template
tRNA
transfer RNA
transcription
the process of copying a segment of RNA into DNA. comes BEFORE translation (remember, you have to transcribe something before you can translate it)
translation
the process by which a cell makes proteines using genetic info in mRNA
