inheritance

define gene

a short section of DNA that codes for a specific protien

define chromosone

thread like structures of dna where the genes are located

define genome

all the dna in an organism

describe structure of dna

double helix

with complementary bases to form the rungs

between the 2 sugar phosphate backbones

what are the 4 dna bases

adenine, thymine, guanine, cytosine

what is mitosis and what is it for

DNA in parent cell is copied + cell splits into 2 genetically identical diploid daughter cells

happens in body cells

needed for growth, repair + asexual reproduction

what is meiosis and what is it for

DNA replicates and splits twice to produce 4 genetically unique haploid daughter cells

happens in sex organs

needed for production of gametes

how does DNA code for proteins

read in triplets - 3 bases make up codon

each codon codes for 1 amino acid

amino acids join to form proteins

the sequence of bases codes for the sequence of amino acids

order of amino acids determines how protein folds + therefore shape of protein

DNA vs RNA

DNA: double stranded, helix, A, T, C, G bases, code for proteins

RNA: single stranded, not helix, A, U (uracil), C, G bases, copy of part of the code

Transcription model answer

RNA polymerase binds to region of DNA just before the gene

DNA strands unzip so 1 can be used as template

RNA polymerase moves along the DNA and uses the template strand to make mRNA by bringing in the complementary bases and joining them to make a single strand

once the mRNA is made, it moves out of the nucleus towards the ribosome

transcription definition

the process of making a copy of genetic information in the form of mRNA

Translation model answer

tRNA molecules have an anticodon at one end and are attached to a specific amino acid at the other end

if the anticodon is complementary to the codon on the mRNA it will pair up, bringing the amino acid with it.

The order of amino acids is determined by the order of codons on the mRNA

the amino acids are joined together by the ribosome to form an amino acid chain

the chain folds to become a protein

translation definition

the process by which the code on the mRNA is used to make a protein. It occurs in a ribosome