DNA and Proteins Flashcards
what is a DNA nucleotide made up of
- nitrogen base (ATCG)
- phosphate
- DEOXYribose suger
what holds the two strands of DNA together in the shape of a double helix
weak hydrogen bonds
what is the shape of DNA in prokaryotic cells
circular, 1 piece of DNA
where is dna located in prokaryotic cells
the nucleoid region (no nucleus)
do prokaryotic cells have membrane bound organelles?
No, they do have ribosomes though
Describe the shape of DNA in eukaryotic cells
Linear (like chromosomes)
describe the shape of DNA
double stranded, double helix
what are the complementary base pairings in DNA
A + T (adenine + thymine)
G + C (guanin + cytosine)
what are the two types of nucleic acid?
DNA (deoxyribonucleic acid)
RNA (ribonucleic acid)
what is the role of DNA
stores and transmits necessary info into cells to direct processes within the body
what are three differences between prokaryotic and eukaryotic cells
- pro has circular DNA, euk has linear DNA
- pro has no nucleus, euk has nucleus
- pro has no membrane bound organelles, euk has membrane bound organelles
what are histones?
Proteins that DNA is attached to
state some differences between RNA and DNA
- RNA has ribose sugar, DNA has deoxyribose sugar
- RNA is single stranded, DNA is double stranded,
- RNA has the base Uracil, DNA has thymine
what is the role of RNA?
TEMPORARILY store genetic material BEFORE cell division
what is a chromatin
chromaTIN (tin of spaghetti) unstructured DNA
what is the centre of a chromosome called
centromere
what is a gene
a section of DNA
what is the purpose of a gene
genes have uniqe base sequences that code for proteins.
different genes have specific locations within DNA and chromosomes. what are these locations called?
locus
what are the two parts of a chromosome that has split called
identical sister chromatids
how many chromosomes do we have?
46, 23 pairs
state the process of DNA REPLICATION/SEMI-CONSERVATIVE REPLICATION
- weak hydrogen bonds are broken by the enzyme helicase, and dna unwinds from double helix
- 2 single template strands are formed.
- free flowing DNA nucleotides are bound to their complementary bases that are exposed on the template strands, by the enzyme DNA polymerase
- new strand is synthesised in a 5 prime to 3 prime direction leading then lagging
- the enzyme ligase seals the sugar/phosphate back bone
- two DNA double helix’s are created. Each contains 1 new and 1 old DNA strand
what are the three types of RNA
mRNA
rRNA
tRNA
what is the role of mRNA
messenger RNA. transcribed from DNA and carries gene message out from nucleus to ribosome for translation into amino acid sequence.
what is the role of rRNA
ribosomal RNA. makes up ribosome, assists with protein synthesis
what is the role of tRNA
transfer RNA. carrier of specific amino acids (anti codon sequence that is complementary to codon on mRNA)
what process follows these steps:
DNA –> RNA–> Protein.
protein synthesis
what are the two processes involved in protein synthesis called?
transcription and translation
where does transcription occur?
in the nucleus of eukaryotic cell
what is the process of transcription?
