Cellular

Question 1

Why is there different sections in the cell for reactions?

Answer 1

Many of the intra-cellular reactions are incompatible

Question 2

What is one way that the cell separates the various reactions?

Answer 2

compartmentalization in membrane bound organelles

Question 3

Since most proteins are hydrophobic, how do the cross the membranes?

Answer 3

Vesicle transporters
Membrane Translocation proteins
Pore - nuclear pores

Question 4

What are the two main protein trafficking pathways?

Answer 4

Secretory Pathway

Default Cyctosolic Pathway

Question 5

What are the potential final destinations of proteins from the secretory pathway?

Answer 5

Outside the Cell
Cell Membrane
Lysosomes

Question 6

What are the potential final destinations of the proteins from Default Cyctocolic Pathway?

Answer 6

Cyctosol
Nucleus
Mitochondria
Perioxsomes

Question 7

If a protein is of the secretory pathway, what will it pass through?

Answer 7

Rough Endoplasmic Reticulum and Golgi Apparatus

Question 8

Where can proteins be synthesised?

Answer 8

Cytosol
Mitrochondria
Rough Endoplasmic Reticulum

Question 9

What determines if a protein is transferred to the RER and where is it located on the protein?

Answer 9

Signal Peptide on the N-terminal of the peptide chain (16-20 amino acids)

Question 10

What binds to the Signal Sequence on the peptide chain to allow it to be recognised by the proteins on the membrane of the RER?

Answer 10

Signal Recognition Particle

Question 11

When the Signal Recognition Particle is stimulated it opens a channel to allow enter for the Peptide with the Signal Peptide?

Answer 11

Translocoon

Question 12

What cleaves the Signal Peptide?

Answer 12

Signal Peptidase

Question 13

What are the three parts of the Golgi Apparatus?

Answer 13

Cis Cisternae, Medial &s Trans Cisternae, Trans Golgi Network

Question 14

As the peptide chain passes through the Golgi Apparatus it fuses with vesicles and passes through getting further post-transnational modification. What is this called?

Answer 14

Cis Maturation Model

Question 15

What post transnational modification occurs in the Golgi apparatus?

Answer 15

Phosphorylation - alters protein activity
Acetlyisation - alters Histone/ Gene activity
Ubiqutatition - degradation
Farnelysation - Targets proteins to the cell membrane and Ras Activity

Question 16

What is added to keep a protein stuck in the cell membrane?

Answer 16

Stop Translocation

Question 17

From the default cytosolic pathway, what is added to send the protein to the nucleus?

Answer 17

Nucleus Localisation Signal

Question 18

What does nuclear bound proteins enter into the nucleus via?

Answer 18

Importin via Importin receptors

Question 19

What Junction disorder leads to Vonwinkel Syndrome?

Answer 19

GAP junctions

Question 20

What type of junction is involved in cell to ECM conenction?

Answer 20

Focal Adhesion

Question 21

What determines the tertiary structure of proteins?

Answer 21

Interactions of the side chain functional groups. including:

• disulfide bonds
• hydrogen bonds
• salt bridges

Question 22

What is the quaternary structure of proteins?

Answer 22

Mutliple sub unit proteins (groups of peptide chains) come together to form a larger molecule through covalent and non-covalent bonds.

Question 23

What factors leave mitochondrial DNA most susceptible to mutations?

Answer 23

Highly oxidative reactions taking place inside it

Lack of histones around the DNA

Question 24

What is it called when thyamine undergoes dimerisation?

Answer 24

Cylobutulythiamine

Question 25

What is homologous DNA repair?

Answer 25

This is where there has been a double stranded break and the DNA is repaired by using a sister chromotid to make the complimentary strand from - which will return to the damaged chromotid and will then be used to fix the other damaged strand

Question 26

What can non homologous DNA repair lead to?

Answer 26

Translocation of chromosomes

Question 27

What is the term used when more than one condon can be used to code for the same amino acid? why is this important?

Answer 27

Degeneracy it allows for some mutations to take place

Question 28

What is the amino acid acceptation to degeneracy? and what does it do?

Answer 28

Methionine is non-degeneracy. codes for starting point of protein synthesis

Question 29

When there is a single amino acid change which leads to a similar protein, what is this called?

Answer 29

Conservative amino acid substitute

Question 30

What does the ribosome scan for in order to carry out translation of the mRNA?

Answer 30

Kozak sequence. this informs it that the next AUG (methionine) is where to start translation