dna and protein synthesis
the process of copying a dna molecule is called ____ ____
dna replication
shape dna is held in which is like a twist ladder
double helix
4 main types of chromosomal mutations
duplication, deletion, inversion, translocation
why is dna replication necessary
each new cell will have the appropriate amount of genetic material
where deos the mRNA transcript go after it exits the nucleus?
enters the cytoplasm and attaches to the ribosome
define gene
unit of inherited information, a section of dna that contains the instructions for making one polypeptide
dna shape was first described by ____ and _____
watson and crick
the 3 parts of the nucleotide
deoxyribose sugar, phosphate, nitrogen base
3 ways in which rna is different from dna
- ribose - CGAU - single strand
the result of dna replication is two new _____ molecules, each with one new strand from the original parent to the new strand
daughter
steps of transcription
1. dna strands separate 2. one side serves as templete 3. mRNA is transcribed from DNA template 4. mRNA transcript is spliced 5. mRNA exits nucleus
steps of translation
1. mRNA attaches to ribosome in the cytoplasm 2. tRNA pairs with MRNA codons 3. amino acids bond to form polypeptide bonds
base deletion
Mutation where one nitrogen base of the DNA is lost and shifts the reading frame. Many amino acids are incorrect.
briefly discuss the structure and function or ribosomes
a ribosome is composed of ribosomal RNA in the form of a large subunit and a small subunit (blue), it holds the mrna transcript and trna molecule
name the three types of rna described below a) transcribes the dna code b) primary component of ribosome c) carries an amino acid into position during translation
a) mRNA b) rRNA c) tRNA
a 3 based word on mRNA that codes for one amino acid is a ____
codon
what is the function of dna?
contains instructions for making proteins
which is worse: base substitution and base deletion
base deletion because it causes a frame shift
2 types of base mutations
base substitution and base deletion
base substitution
changes the base of a single DNA nucleotide
what does dna stand for?
deoxyribonucleic acid
4 nitrogenous bases in dna and how the pair up
guanine - cylosine (G-C) adenine - thymine (A-T)
nitrogen bases in dna are held together by ____ bonds
hydrogen
eukaryotic genes contain non-coding regions called _____ and coding regions called _____
introns and exons
any change in the DNA sequence
mutation
dna is a polymer made of ____ monomers
nucleotides
where does transcription take place? what is formed?
occurs in nucleus and forms mRNA
during dna replication the molecule unzips at ____ of _____ forming replication bubbles
origins of replication
your dna contains the instructions for making your _____ and these determine your _____
proteins; traits
rna ____ involves removing the introns and joining the exons together to form mRNA transcript
splicing
dna nucleotides are joined by covalent bonds between the ___ of one nucleotide and the ___ ___ of the next
sugar; phosphate group
list the 2 main steps of protein synthesis
transcription and translation
· 20 different ______ link together to form chains · a protein is composed of one or more of these ____ chains which are twisted and folded into a particular shape
· amino acids · polypeptide chains