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Flashcards in Storing using genetic information Deck (25):
1

Define phenotype

the outward physical genes expressed

2

Define genotype

The full hereditary information of an organism

3

What is DNA a chain of

Nucleotide monomers

4

What is a nucleotide composed of

Deoxyribose
Base
Phosphate group

5

Why is it deoxyribose the sugar in DNA

Bonds are more attracted to each other due to reduced polarity making DNA more stable as harder to separate

6

what is the structure of DNA
and the direction

Double helix
right hand twist

7

What are the four bases of DNA

Adenine
Guanine
Thymine
Cytosine

8

What are the bonds that join the bases
and What is the the pairing of DNA bases

Hydrogen
Adenine - thymine
Cytosine - guanine

9

What maintains the shape of the DNA double helix

Sugar phosphate backbone

10

Where does DNA replication take place

Nucleus

11

What direction is DNA synthesis

5-3 direction

12

What are the steps of DNA replication

1. Enzymes break hydrogen bonds and DNA unwinds
2. New nucleotide molecules pair with two DNA strands
3.Replication occurs in 5-3 direction by enzyme DNA polymerase on leading strand
4. Lagging strand replicated in fragments which are then joined by DNA ligase and DNA polymerase adding on Nucleotides

13

What does it mean that DNA is bidirectional

5 prime to 3 prime DNA run antiparallel to each other

14

What is the fragmentation called in DNA replication

okazaki

15

How is DNA replication semi-conservative

one half of DNA made is new where the other strand is old DNA

16

What are the codon region in DNA

exons

17

How is the base sequence of DNA transcribed into RNA

1. mRNA enters nucleus and transcribes DNA with nucleotides coding only with the exons
2. mRNA then is transported out of the nucleus into the cytoplasm

18

What is it called when mRNA only codes exons and eliminates introns

alternative splicing

19

What happens post transcription

The base sequences frames are read and segmented into each 3 bases create a codon specific for a particular amino acid

20

What happens in the translation of mRNA

1. mRNA binds to ribosomes (rRNA) in the cytoplasm
2. tRNA binds anticodons to mRNA coding sequence
3. tRNA then brings in specific amino acids
4. passes amino acid along forming peptide chain
5. Peptide chain is then transported to golgi apparatus where they are synthesised and packaged into proteins

21

Where is ribosome/rRNA produced

nucleus

22

What is degeneracy

more than one codon codes for an amionacid

23

What can a single point mutation cause

dysfunctional protein

24

Example of a single point mutation

sickle cell anaemia

25

what is a polysome

several ribosomes translating mRNA at the same time