IMMS

Question 1

Describe Peptide Hormones

Answer 1

Made from amino acids
Water Soluble
Binds to cell surface membrane 
Fast acting
Premade and stored
E.G. ADH, Insulin

Question 2

Describe Steroid Hormones

Answer 2

Made from cholesterol 
Lipid Soluble, need transport protein to travel in blood
Diffuses through cell surface membrane
Slow acting
Not premade
E.g oestrogen, testosterone

Question 3

How much of the water in average human is ICF

Answer 3

28L (66%)

Question 4

How much water in an average human is ECF?

How is this distributed?

Answer 4

14L (33%)

Interstitial fluid 11L, Plasma 3L

Question 5

Examples of sensible water loss

Answer 5

Urine/ vomit

Measurable

Question 6

Examples of insensible water loss

Answer 6

Sweat, breath

Immeasurable

Question 7

What cells in Kidney detect low NaCl

Answer 7

Macula Densa (in distal convoluted tubule)

Question 8

What cells detect low Blood Pressure in the Kidneys

Answer 8

Juxtaglomeruler cells in afferent arteriole

Question 9

What cells release renin

Answer 9

Juxtaglomeuler

Question 10

What does ADH act on in the kidneys

Answer 10

AP-II protein in the collecting ducts

Increase permeability so more water retained

Question 11

Where is ADH released from

Answer 11

Posterior Pituitary

Question 12

Where is ADH made

Answer 12

Hypothalamus

Stored in pituitary

Question 13

What is the affect of aldosterone

Answer 13

Increase Na+ reabsorption in ascending limb of loop of Henle

Question 14

What is obligatory H2O movement

Answer 14

Water following the movement of Na+

Question 15

Where is aldosterone released from

Answer 15

Suprarenal cortex

Question 16

What is released by blood vessels (and myocytes of heart) when they become too dilated due to hugh blood pressure.
(High stress on walls)

Answer 16

Atrial natriuretic peptide

Is an antagonist to aldosterone so decreases blood pressure

Question 17

Define osmolality

Answer 17

Conc. /kilo solution

Question 18

Define osmolarity

Answer 18

Conc. /Litre of solution

Question 19

Osmotic pressure

Answer 19

Pressure exerted by pure solvent on solution needed to prevent inward osmosis
(Solvent➡️ solution)

Question 20

Oncotic pressure

Answer 20

Protein pressure (albumin) on capilly walls keeping fluid in

Question 21

Hydrostatic pressure

Answer 21

Fluid pressure wanting to move out of capillary

Question 22

What is it called when you have excess/ less Na+

Answer 22

Hyper/hyponatremia

Question 23

Causes and symptoms of hypernatremia

Answer 23

Causes:- dehydration, ⬆️aldosterone, failing kidneys

Symptoms:- Oedema, ⬆️BP

Question 24

Causes and symptoms of hyponatremia

Answer 24

Casues:- excess water, ⬇️aldosterone

Symptoms:- ⬇️BP, overhydrated intracellulary

Question 25

What is excess/ less K+

Answer 25

Hyper/hypokalemia

Question 26

Causes and symptoms of hyperkalemia

Answer 26

Causes:- Kidney failure, ⬇️aldosterone, alkalosis Symptoms:- nerve and muscle issues

Question 27

What is Excess/ less calcium

Answer 27

Hyper/hypocalcemia

Question 28

Causes and symptoms of hypokalemia

Answer 28

Causes:- diarrhoea, ⬆️ aldosterone Symptoms:- weakness, heart problems

Question 29

What bond Binds carbohydrates

Answer 29

Glycosidic bonds

Question 30

Describe triglycerides

Answer 30

Hydrophobic Esterbond Main energy source (9kcal/g) by fatty acid beta oxidation Used for protection, lubrication, waterproofing

Question 31

Phosolipids are amphipathic, what does this mean

Answer 31

A molecule with both hydrophilic and hydrophobic parts. (Negative head)

Question 32

Describe nucleotide

Answer 32

Phosphate + pentose sugar + base | Phosphodiester bonds between 3'C + 5'C on sugar

Question 33

Describe nucleoside

Answer 33

Pentose sugar + base (no phosphate)

Question 34

What are purines and pyramidine

Answer 34

Purine have 2 rings A + G Pyramidines have 3 rings C + T + U 1 purine will bind to one pyramidine

Question 35

How many amino acids are there

Answer 35

20 naturally occuring, 8 are essential (must get through diet)

Question 36

On which amino acids would you find disulfide bridges

Answer 36

S=S on cysteine

Question 37

Compare adult and fetal haemoglobin

Answer 37

Adult is 2 alpha chains, 2 beta chain | Fetal is 2 alpha chains, 2 gama chains (⬆️O2 affinity)

Question 38

Describe sickle cell anemia

Answer 38

Autosomal recessive disease Mutated beta chain Mutation occurs on 11p (small arm of chromosome 11) GAG~ GTG (Substitution) Valine coded for instead of Glutamic acid Makes RBA have lower surface area (sickled) RBA less flexible and more prone to damage

Question 39

In DNA replication what unwinds the supercoil?

Answer 39

Topoisomerase

Question 40

In DNA replication, what breaks the H bonds between strands

Answer 40

Helicase

Question 41

Once the 2 strands are separated, what prevents them rejoining?

Answer 41

Single strand bases (SSBs) | Bind to exposed bases

Question 42

What is the role of DNA polymerase

Answer 42

Forms phosphodiester bonds between between free nucleotides to form new strand

Question 43

How does DNA polymerase read DNA and how does it synthesise it?

Answer 43

Reads 3⁰ to 5⁰ | Synthesise 5⁰ to 3⁰

Question 44

What is the role of DNA ligase

Answer 44

Joins ozaki fragments on the lagging strand by phosphodiester bonds

Question 45

Where does transcription occur

Answer 45

Nucleus

Question 46

What is the TATA box region

Answer 46

The promoter region for transcription. | Always starts with codon AUG (methionine)

Question 47

Where does translation take place

Answer 47

Cytoplasm

Question 48

Where does mRNA bind

Answer 48

Small subunit of ribosome

Question 49

Where does tRNA bind

Answer 49

Large subunit of ribosome

Question 50

What happens in G1 of the cell cycle

Answer 50

Organelles replicate | Not DNA

Question 51

What is the G1 checkpoint

Answer 51

The cells checks for DNA damage pre DNA replication.

Question 52

What happens if DNA damage is detected at the G1 checkpoint

Answer 52

Activates tumour suppressor gene p53 which leads to a cascade of events eventually ending either autolysis

Question 53

What happens in the S phase of the cell cycle

Answer 53

DNA replication

Question 54

What happens at the G2 checkpoint

Answer 54

Checks for DNA damage pre mitosis, | Damaged bases removed by glycosylases

Question 55

In what phase of meisos does crossing over take place

Answer 55

Prophase 1

Question 56

In what stage of meiosis does independent segregation occur

Answer 56

Metaphase 1

Question 57

When will meiosis 2 take place in oogenesis

Answer 57

When the egg is fertilised

Question 58

What is non-disjunction

Answer 58

Failure to separate in M1 or M2

Question 59

What is gonadal mosaicism

Answer 59

Healthy patient has a mutated Germline

Question 60

What is a polymorphism

Answer 60

Non pathogenic variations at a locus from a wild type (normal allele)

Question 61

What is consanguinity

Answer 61

2 relatives union (reproductive)

Question 62

Penetrance

Answer 62

% of people with expected phenotype from their genotype

Question 63

Variable expression

Answer 63

Some genotypes may have different expressions

Question 64

Late onset

Answer 64

Manifestation after birth later in life | vs at birth, congenital

Question 65

Autozygosity

Answer 65

Same mutation from both sides of the family

Question 66

Anticipation (in reference to genetic disorders)

Answer 66

Wider trinucleotide repeates of mutated sequence over generations (Earlier and more severe each time) E.g Huntingtons

Question 67

What does Hemizygous mean

Answer 67

Genes come from an unpaid chromosome | E.g. men are hemizygous for genes on y

Question 68

Lyonisation

Answer 68

1 female X randomly inactivated

Question 69

Imprinting

Answer 69

1 allele suppressed (imprinted) of the 2 inherited

Question 70

Sex limitation

Answer 70

Gene defect affects 1 sex only

Question 71

What is the carrier frequency of cystic fibrosis in the UK

Answer 71

1/25

Question 72

What js the defect that causes cystic fibrosis

Answer 72

Defect in gene F508 | Most common auto recessive affecting whites in UK

Question 73

What is the Hardy weinberg equation

Answer 73

p+q=1 p^2 + 2pq + q^2 = 1 ``` p^2 = Homozygous dominant 2pq = heterozygous q^2 = homozygous recessive ```

Question 74

What is the incidence of Cystic Fibrosis

Answer 74

1/2500

Question 75

What is a tandem duplication mutation

Answer 75

Adjacent repeating bases

Question 76

What is a non-tandmem mutation

Answer 76

Repeating bases at another locus

Question 77

What is an inversion mutation

Answer 77

DNA segment reversed Parametric:- outside centromere Pericentric:- includes centromere

Question 78

Translocation mutation

Answer 78

Exchange with non homologous chromosome

Question 79

What does a karyotype show

Answer 79

Numerical configuration of chromosomes

Question 80

What does an ideogram show

Answer 80

Distinct banding patterns of chromosomes

Question 81

How many kcal/g are there in carb, protein, fat, alcohol

Answer 81

Carb=4 Protein=4 Fat=9 Alcohol=7

Question 82

How grams of alcohol are there in 1 unit

Answer 82

8g | 10ml

Question 83

In the absorptive state, do you have higher or lower Insulin levels

Answer 83

Higher | Less glucagon

Question 84

Where is fat stored

Answer 84

Adipocytes | Ito cells

Question 85

Where are carbs stored

Answer 85

Skeletal muscle | As glycogen