Unit 1

Question 1

what is the proteome

Answer 1

the proteome is the entire set of proteins expressed by a genome

Question 2

what factors affect the set of proteins expressed by a given cell type

Answer 2

metabolic activity of the cell, cellular stress, response to signalling molecules and healthy vs diseased cells

Question 3

what is the difference between the two ERs

Answer 3

Rough endoplasmic reticulum has ribosomes on its cytosolic face whereas smooth endoplasmic reticulum lacks ribosomes

Question 4

what is the Golgi apparatus

Answer 4

the Golgi apparatus is a series of connected flattened membrane discs to allow molecules to move within the apparatus. the Golgi apparatus is adjacent to the endoplasmic reticulum.

Question 5

what are lysosomes

Answer 5

membrane bound organelles containing a variety of hydrolyses that digests proteins lipids, nucleic acids and carbohydrates. they are acid allowing optical function of its enzymes.

Question 6

what is the site of lipid synthesis

Answer 6

smooth endoplasmic reticulum

Question 7

where is the site of protein synthesis

Answer 7

the synthesis of all proteins start and end in the cytosolic ribosome then the proteins remain in the cytosol.

Question 8

what are examples of post translational modification

Answer 8

proteolytic cleavage, phosphorylation and adding functional groups

Question 9

what is the basic structure of amino acids

Answer 9

central carbon, amine (NH2), carboxylic acid (COOH), a hydrogen and a variable R group.

Question 10

what are the features of an acidic amino acid

Answer 10

carboxylic acid (COOH) group, hydrophilic

Question 11

what are the features of a basic amino acid

Answer 11

Amine group, hydrophilic

Question 12

what are the features of a polar amino acid

Answer 12

C=O, OH or NH group, hydrophilic

Question 13

what are the features of an hydrophobic amino acid

Answer 13

hydrocarbon group, hydrophobic

Question 14

what causes the range of functions of amino acids

Answer 14

the R groups which vary in size, shape, charge, hydrogen bonding capacity and chemical reactivity.

Question 15

what is the primary structure of a protein

Answer 15

the sequence in which the amino acids are synthesised into the polypeptide

Question 16

what are the three types of tertiary structure

Answer 16

alpha helix, beta sheet and turns

Question 17

which amino acid is the main driving force of protein folding

Answer 17

hydrophobic as hydrophilic predominate at the surface of a soluble protein

Question 18

what bonds are found in proteins

Answer 18

hydrogen bond and disulphide bonds.

Question 19

what is quaternary structure of proteins

Answer 19

protein with two or more connected polypeptide subunits.

Question 20

what are the non protein binding units necessary for proteins function

Answer 20

prosthetic groups

Question 21

what are allosteric proteins

Answer 21

allosteric proteins have quaternary structure and multiple binding sites, when a substrate binds to one of these sites the affinity of the others alters. this means activity of enzymes can vary greatly with small changes of substrate concentration

Question 22

how does pH and temperature affect affinity

Answer 22

as temperature increases affinity decreases and as pH increases affinity increases

Question 23

what do modulators do

Answer 23

modulators change the conformation of allosteric proteins. positive modulators increase affinity, negative modulators decrease affinity

Question 24

what enzyme os responsible for the phosphorylation of proteins

Answer 24

kinase

Question 25

what enzyme os responsible for the dephospho-rylation of proteins

Answer 25

phosphatase

Question 26

what are the two membrane protein types

Answer 26

integral and peripheral

Question 27

What are the specific sites on DNA that hormone response complexes bind to

Answer 27

hormone response elements, which directs influence the rate of transcription

Question 28

what is the cytoskeleton

Answer 28

the network of proteins extending throughout the cytoplasm is known as the cytoskeleton

Question 29

what protein are microtubules composed of?

Answer 29

tubulin radiations from the centrosome

Question 30

what does the cell cycle compose of

Answer 30

G1 phase DNA synthesis, S phase DNA Replication, M phase and G2 phase further DNA growth

Question 31

what are the stages of mitosis

Answer 31

interphase, prophase, metaphase, anaphase, telophase

Question 32

what protein is involved in regulating the cell cycle

Answer 32

cyclin with combine to cyclin dependent kinases to phosphorylate proteins that regulate progression through the cycle

Question 33

what is the result of uncontrolled reduction in the rate of the cell cycle

Answer 33

degenerative disease

Question 34

what is the result of an uncontrolled increase in the rate of the cell cycle

Answer 34

tumour formation

Question 35

what is apoptosis and how is it brought upon

Answer 35

triggered by internal or external death signals such as DNA damage from lymphocytes. death signals bring upon activation of caspases that cause destruction of the cell

Question 36

what does an internal death signal resulting from DNA damage do

Answer 36

activates p53 tumour suppressor protein

Question 37

Name the class of enzyme found within lysosomes.

Answer 37

hydrolase

Question 38

Describe the role of vesicles.

Answer 38

Transport materials between membrane compartments.

Question 39

Define the term facilitated diffusion.

Answer 39

The passive transport of substances across the membrane through specific transmembrane proteins.

Question 40

Describe the relationship between the sodium-potassium pump and glucose symport in the small intestine.

Answer 40

The sodium gradient created by the sodium-potassium pump drives the active transport of glucose.

Question 41

What type of protein are the receptors for steroid hormones?

Answer 41

Transcription factors

Question 42

What is an action potential?

Answer 42

A wave of electrical excitation along a neuron's plasma membrane.

Question 43

Describe the role of CDKs.

Answer 43

They phosphorylate proteins that regulate progression through the cycle.

Question 44

Describe one role of p53 protein.

Answer 44

stimulate DNA repair; stop/arrest the cell cycle; cause cell death/apoptosis

Question 45

Give an example of an internal death signal.

Answer 45

DNA damage

Question 46

Give an example of an external death signal.

Answer 46

lymphocytes

Question 47

What term described the pH at which a soluble protein had no net charge and will precipitate out of solution

Answer 47

Isoelectric point

Question 48

What is a haemocytometer used for

Answer 48

To estimate cell numbers in a liquid culture

Question 49

Describe the cause of type 2 diabetes

Answer 49

Loss of insulin receptor function