Chapter 4 - DNA & RNA Flashcards
Name the 3 elements that make up DNA
Phosphate, deoxyribose sugar and a base
What are chromosomes and genes made from?
DNA
Is DNA a parallel molecule?
No it is anti-parallel
How are the bases held together?
Weak hydrogen bonds
Name the 4 bases present in DNA
Adenosine
Thymine
Guanine
Cytosine
Adenosine always pairs with..
Thymine
Guanine always pairs with..
Cytosine
State 3 differences between RNA and DNA
DNA is double stranded, RNA is single stranded
RNA has uracil instead of thymine
DNA contains deoxyribose sugar, whilst RNA contains ribose sugar
Name two things you need for DNA replication
Free nucleotides
DNA polymerase
ATP
DNA template
Describe step 3 in DNA replication
Free nucleotides match up to complementary base pairs and weak hydrogen bonds form
An anti-codon is made from..
3 tRNA bases
A codon is made from..
3 DNA or mRNA bases
What does the sequence of bases code for?
Sequence of amino acids
How many bases code for an amino acid?
A triplet (3) bases
One gene codes for..
One protein
What is needed for protein synthesis?
Free RNA nucleotides
ATP
Enzymes
Gene
Where does transcription take place?
Nucleus
Roughly, describe what happens in transcription as a whole
mRNA takes the code for the proteins from the DNA in the nucleus
Where does translation take place?
Ribosomes in the cytoplasm
Roughly, describe what happens in translation
tRNA transports specific amino acids, according to the mRNA strand to the ribosome to be synthesised. Peptide bonds form between adjacent amino acids to form a polypeptide
Where in the cell are proteins packaged and processed?
Golgi Apparatus
Name the 4 main elements that make up proteins
Nitrogen
Oxygen
Hydrogen
Carbon
What is the primary structure in a protein?
Peptide bond holding the amino acids together
What is the secondary structure in a protein?
Weak hydrogen bonds between amino acids on a polypeptide chain
What proteins are long parallel strands?
Fibrous
Globular proteins are..
Spherical in shape
Conjugated proteins are..
Globular proteins combined with a non-protein part
Give 2 examples each for : Fibrous, globular and conjugated proteins
F- collagen, actin, mysosin, keratin
G- pepsin, anti-bodies, insulin
C- haemoglobin, mucus
