1. intro to cells

Question 1

plasma membrane function

Answer 1

• protection
• transport
• communication

Question 2

key components of plasma membrane

Answer 2

• phospholipids
• cholesterol
• proteins

Question 3

types of membrane proteins

Answer 3

• integral
• peripheral

Question 4

integral proteins

Answer 4

anchored to membrane (either partially or transmembrane)

Question 5

peripheral proteins

Answer 5

on outside or inside of membranes

Question 6

how do cell signals get inside cells

Answer 6

• diffusion
• enter through channels or carriers
• they don’t enter

Question 7

cytoskeleton

Answer 7

• maintains cell shape and structure
• helps with internal organisation

Question 8

cytoskeleton components

Answer 8

• microtubules
• microfilaments
• intermediate filaments

Question 9

microtubules

Answer 9

rows of tubulin dimers form a tube
- resist compression
- maintains cell shape
- important for motility (flagella, cilia, organelle motility)

Question 10

microfilaments

Answer 10

actin subunits forming rope-like filaments
- resist tension
- form cortical network beneath plasma membrane
- important for muscle contractions

Question 11

intermediate filaments

Answer 11

coiled fibrous keratin proteins
- form more permanent structures
- anchor organelles
- important in cell adhesion

Question 12

steps of cell signalling

Answer 12

• synthesis of signal molecule
• release of signal molecule
• transport of signal molecule
• detection of signal molecule
• cellular response
• feedback

Question 13

signalling pathway specificity

Answer 13

• direct contact
• selective receptor expression
• degradation/ reuptake of signal molecule

Question 14

signalling modes

Answer 14

• juxtacrine
• autocrine
• paracrine
• endocrine
• neuronal

Question 15

juxtacrine specificity

Answer 15

direct contact required (and receptor expression sometimes)

Question 16

autocrine specificity

Answer 16

selective receptor expression and rapid degradation of signal molecule

Question 17

paracrine specificity

Answer 17

selective receptor expression and rapid degradation of signal molecule

Question 18

neuronal specificity

Answer 18

precise contacts and rapid removal of neurotransmitters

Question 19

endocrine specificity

Answer 19

selective receptor expression

Question 20

signal ligand types

Answer 20

• lipid soluble
• water soluble
• gases

Question 21

common ligands

Answer 21

• hormones (eg. testosterone, insulin, IGF-1)
• neurotransmitters (eg. acetylcholine and Epinephrine)

Question 22

second messengers

Answer 22

• small molecules that relay signal from receptor to effector protein
• often can be synthesised, released, and degraded by enzymes

Question 23

common membrane associated second messengers

Answer 23

• diacylglycerol (DAG)
• phosphatidylinositol (PI)

Question 24

common cytosol second messengers

Answer 24

-cAMP
-cGMP
-inositol triphosphate (IP3)
- Ca2+