IMMS HS

Question 1

Homeostasis

Answer 1

the maintenance of stable internal conditions within the body

Question 2

cell communication

• autocrine
• paracrine
• endocrine

Answer 2

• within the same cell
• signal effects nearby cells
• signal secreted into blood

Question 3

Feedback

• positive=
• negative=

Answer 3

• amplification process–>chain reaction

- result of action inhibits another action

Question 4

VIP

water distribution

Answer 4

2/3 intracellular
1/3 extracellular:
-80% extracellular space
-20% plasma

Question 5

osmoregulation

Answer 5

(dehydration)

1. low water levels detected by hypothalamic osmoreceptors
2. osmoreceptors send signal to pituatary to release ADH
3. ADH travels to kidney = increases fluid uptake

Question 6

fluid loss

• sensible
• insensible

Answer 6

• can be measured - urine, faeces, breathing

- evapration from the skin

Question 7

osmolality

Answer 7

conc. of solutes in plasma per kg of solvent

Question 8

osmolarity

Answer 8

conc. of solutes in plasma per litre of solution

Question 9

osmotic pressure

Answer 9

how easily solution can take in water vs oncotic pressure: specific type of osmotic pressure concerning albumin

Question 10

oedema

Answer 10

increased movement of fluid from plasma to interstitial space, or decrease in vice verse

Question 11

types of oedema (4)

Answer 11

normal-increased hydrostatic pressure forces fluid out of vessels
inflammatory-histamine increases bl vessel permeability
lymphatic=lymph system doesn’t remove fluid from extracellular space
hypoalbuminaemic-decreased albumin=decrease oncotic pressure

Question 12

carbohydrate

Answer 12

6xC monosaccharides

glycosidic bonds form between monosaccharaides to produce disacharrides/polysacharrides (condensation reaction)

Question 13

lipid

Answer 13

hydrophobic

triglyceride - glycerol head with 3 fatty acid tails

Question 14

nucleotide (structure)

Answer 14

nitrogenous base
pentose sugar
phosphate group

Question 15

nucleotide

Answer 15

phospodiester bonds form between adjecent nucleotides

hydrogen bonds form between opposite nucleotides

Question 16

amino acid (structure)

Answer 16

central C atom attached to amine gp, carboxyl gp, H gp, variable gp

Question 17

amino acids

Answer 17

peptide bonds form in condesation reactions

Question 18

protein structure

1st to 4th

Answer 18

primary- specific sequence of amino acids
secondary- alpha helix and beta pleated sheet
tertiary- folding onto 3D shape
(disulphide bridges, H bonds and polar regions)
quartery- multiple tertiary proteins working together (haemoglobin)

Question 19

enzyme (4)

Answer 19

biological catalyst
protein and non-protein component
induced fit theory
coenzyme= non-protein component

Question 20

intermolcular forces (weak to strong)

Answer 20

: Van der Waals -> permanent dipole -> H bonds

Question 21

cell cycle (4)

Answer 21

G1 phase-cellular contents are replicated
S p-chromosomes are replicated
G2 p-replication is checked for errors and components are assembled/arranged

Question 22

mitosis (7)

Answer 22

1) Interphase: G1->S->G2 phases (can’t see)
2) Prophase: chromatin condenses to visible chromosomes, AND centrioles migrate to poles of cell
3) Prometaphase: nuclear membrane breaks down AND microtubules from centrioles bind to centromeres
4) Metaphase: chromosomes line up in middle of cell (metaphase plate)
5) Anaphase: sister chromatids are pulled apart to opposite ends of cell by microtubules
6) Telephase: nuclear membranse reforms AND chromosomes decondense to form chromatin
7) Cytokinesis: cytoplasm divides to form 2 daughter cells

Question 23

meiosis (3)

Answer 23

1. Interphase: cell contents replicate (2n->4n)
2. Meiosis 1: mitosis, but crossing over and independent assorment occurs (4n->2n)
3. Meiosis 2: daughter cells divide to form haploid cells

Question 24

Meiosis
numerical abnormalities (2)

Answer 24

during meiosis 1 or 2 chromosomes are not divided up equally
Down’s syndrome (3x 21)
Turners (x1)

Question 25

``` Meiosis structural (3) ```

Answer 25

- chromosomes (or bits of) swap places during meiosis 1 + 2 - different sized chromosomes - less serious than numerical as genetic info still present

Question 26

gametogenesis

Answer 26

meiosis to form gametes

Question 27

Mendal's 2nd law

Answer 27

the hereditary box crossover diagram (dominant and recc. alleles)

Question 28

gonadal mosaicism

Answer 28

epigenetics mean environmental factors (mainly age) cause sperm/egg to have different genetic information to father/mother

Question 29

allele

Answer 29

different forms of genes | many within chromosome

Question 30

genotype

Answer 30

genetic makeup of an individual

Question 31

phenotype

Answer 31

observable characteristics of an individual (gens and environment working together)

Question 32

inheritance (2)

Answer 32

mendelian: purely genes multifactorial: combination of genes and environment

Question 33

autosomal dominant

Answer 33

condition presents in heterozygous state - polysistic kidneys, huntingtons

Question 34

autosomal recessive

Answer 34

only presents homozygous ie cystic fibrisis, sickle cell aneamia

Question 35

X-linked inheritance (4)

Answer 35

- genes carried on maternal x chromosome - unaffected female carriers (predominantly male) - heamophilia, muscular dystropy - faulty gene can be active or inactive

Question 36

Lyonisation (3)

Answer 36

- random process - one of the maternal X chromosomes inactivated - gene can be active or inactive

Question 37

Knudson's 2 hit hypothesis

Answer 37

cancer result of accumulated mutations to cell DNA | -relates to discovery of cancer genes anf carcinogenesis

Question 38

Multifactorial diseases (3)

Answer 38

combination of genes and environment risk of condition is highest in relations of 'diseased' schizophrenia, cancer, Alzheimer's

Question 39

penetrance

Answer 39

% individuals with specific genotype showing expected phenotype

Question 40

variable expression

Answer 40

individuals with same genotype may have differing phenotypes

Question 41

anticipation

Answer 41

genetic defects affect successive generations early and more severly, due to repeat triplet sequences

Question 42

metabolism

Answer 42

chemical processes occuring within the body to maintain life

Question 43

basal metabolic rate

Answer 43

rate of energy use in the body for vital functions at rest | affected by: age, gender, body size, composition