IMMS

Question 1

DNA

Answer 1

Chromatin- Euchromatin: loose coils expressed. Heterochromatin: tight coils, repressed

Nucleolus -RNA synthesis

Question 2

Mitochondria

Answer 2

ATP synthesis

Question 3

SER

Answer 3

Membrane lipid synthesis, protein storage
Phase 1 detoxification

Question 4

RER

Answer 4

Protein synthesis

Question 5

Golgi apparatus

Answer 5

cis: receives protein/lipid vesicles
medial: add sugar to these
trans: package modified molecules into vesicles, exocytosis

Question 6

Perinuclear Hoff:

Answer 6

Plasma cells: Golgi

Question 7

Lysosomes

Answer 7

Degrades protein + cell autolysis

Low pH maintained by H+/K+ ATPase

Question 8

Peroxisomes

Answer 8

Type of vesicle

Beta oxidation of FA

Produces (+destroys) H2O2 (→0H)

Removes H from lipid/ alcohol/ toxic substances

Question 9

Cytoskeleton

Answer 9

Microtubules = 25micrometres

-Tubulin motor protein: arranged as Alpha + Beta structure; a DIMER

Function: Mitosis, a component of cilia

Intermediate filaments = 10nm

no motor protein

Function: cell integrity + cell cell contract

Microfilament: 5-7nm

myosin motor proteins

Function: cell shape + motility

-

Question 10

Storage Products in cell

Answer 10

Lipofuscin: “wear + tear” pigment (oxidative lipid degradation). In old cells. Orangey brown

Lipids: pale white storage, stored in adipocytes

Glycoprotein: glucose reserve, in skeletal muscle + liver

Question 11

Membrane proteins

Answer 11

Receptors: Outside binding triggers intracellular response

• Enzyme-linked/ ion channels
• G- coupled protein: extracellular binding activates the transduction pathway internally. Cascade of internal reactions
• Channels

Ligand-gated ( depends on the

ligand binding to it)

Voltage gated

Mechanical gated (open when stretched)

Question 12

Cell to cell junctions

Answer 12

Tight junctions: no passage, cells sealed like a sheet e.g in G.I tract, BBB

Adherens: Adjacent actin (bundle of cells joined).

Desmosomes: adjacent intermediate filaments (bigger) joined

Gap junctions: allows adjacent cells passage of ions

Key in myocardium contraction

Question 13

Types of endocytosis

Answer 13

Phagocytosis

Pinocytosis

Receptor-mediated

Question 14

Homeostasis + Communication

Answer 14

Def: Maintenance of constant internal conditions at a normal range

Autocrine: acts on the same cell, secretin into ECF

Paracrine: secretion into ECF, acts on neighbouring (nearby) cell

Endocrine: secretion into the blood, acts on target cell

Question 15

Hormones

Answer 15

Peptide: made from a.a

water-soluble

binds to CSM surface

Fast-acting

Prepared and Stored

Steroid hormone:

Question 16

Water distribution 70kg male

Answer 16

42l →

ICF= 28L K+

ECF (Na+)= 14L → IF: 11L (outside BV)

Plasma = 3L(inside BV)

Question 17

Osmolarity vs osmolality

Answer 17

Osmolarity: the number of substances dissolved per litre of solvent

Osmolality: Amount of substances per kg of solvent

Question 18

Osmotic pressure

Answer 18

the pressure exerted by a pure solvent on a solution to prevent inward osmosis (solvent → solution)

Question 19

Oncotic pressure

Answer 19

Albumin pressure on the capillary wall keeping fluid in

Question 20

Hydrostatic pressure

Answer 20

Fluid pressure wants to move out of the capillary

Question 21

Ion balance

Answer 21

Na+: Hypernatremia, Hyponatremia

K+: Hyperkalaemia

Hypokalaemia

Ca+: Hypocalcaemia

Hypercalcemia

Question 22

Nucleotide vs nucleoside

Answer 22

Nucleotide: pentose sugar with a base + phosphate

Nucleoside: pentose with base+ base

Question 23

Purine vs pyrimidine

Answer 23

Purine has 2 rings

Pyrimidine has 3 rings