Proteins

Question 1

What are proteins uses? 8

Answer 1

• enzymes
• defence (antibodies)
• transport
• storage
• hormones
• receptors
• contractor and motor proteins
• structural

Question 2

Why do we eat some amino acids (essential)?

Answer 2

Essential amino acids are the ones that the body doesn’t make, so we have to eat food that contains it

Question 3

Primary structure of protein

Answer 3

• the list of amino acids in order from terminus and interminus

Question 4

Secondary protein

Answer 4

• chains of amino acids in a parallel or antiparallel sheet (beta sheet) sheet into helix –> alpha helix

Question 5

tertiary structure (the fold)

Answer 5

• beta sheet, alphahelix and other bits combine to fold up in space

Question 6

How to tertiary structures stay together?

Answer 6

to maintain and stabilise structure, disulfide bridge, and Van der Waal’s forces are present.

Question 7

Quaternary structure?

Answer 7

• multiple folded subunits and folded proteins

Question 8

Helicase function?

Answer 8

Unwinds parental double helix at replication fork

Question 9

Single-strand binding protein function?

Answer 9

Binds to and stabilises single-stranded DNA until it is used as a template

Question 10

Topoisomerase function?

Answer 10

relieves overwinding strain ahead of the fork by breaking, swivelling and rejoining DNA strands

Question 11

Primase function?

Answer 11

synthesis for RNA primer at 5’ end of the leading strand and at 5’ end of each Okazaki fragment of the lagging strand

Question 12

DNA pol iii

Answer 12

using parental DNA as a template synthesises new DNA strand by adding nucleotides to RNA primer

Question 13

DNA poll i

Answer 13

removes RNA nucleotides of primer from 5’ end and replaces with DNA nucleotides

Question 14

DNA ligase?

Answer 14

Joins Okazaki fragments of lagging strand; on leading strand joins 3’ end of DNA that replaces primer to rest of leading strand DNA.