2 - Nerve & muscle part one

Question 1

phospholipid bilayer definition

Answer 1

two layer orchestration of phosphate and lipid molecules that form a cell membrane

Question 2

what model in important for neurotransmission?

Answer 2

fluid mosaic model

Question 3

What is polar and non polar in the plasma membrane?

Answer 3

head is polar and tail is non polar

Question 4

What does the head of the phospholipid molecule contain? And how does it react with water?

Answer 4

Contains a phosphate group which makes is hydrophilic

Question 5

hydrophilic definition

Answer 5

water loving

Question 6

hydrophobic definition

Answer 6

water hating

Question 7

why is the head of the phospholipid polar?

Answer 7

because the phosphate group is negatively charged

Question 8

what does the tail of the phospholipid molecule have and it’s reaction to water?

Answer 8

lipid (fatty acid) and hydrophobic

Question 9

the tail of the phospholipid molecule is ——

Answer 9

non polar

Question 10

how do the 2 layers of phospholipid molecules sit?

Answer 10

heads face outwards - one to extracellular fluid and other head faces the intracellular fluid

Question 11

Integral membrane proteins are located where?

Answer 11

permanently embedded within the plasma membrane

Question 12

Integral membrane proteins can be classified in 2 ways

Answer 12

Transmembrane proteins and Integral monotopic proteins

Question 13

Transmembrane proteins location in the membrane and where it’s found

Answer 13

span the entire plasma membrane - found in all types of biological membranes.

Question 14

Integral monotopic proteins location

Answer 14

permanently attached to the membrane from one side

Question 15

peripheral proteins are —- and attached to?

Answer 15

temporarily attached to the cell or membrane

Question 16

peripheral proteins can be

Answer 16

enzymes, involved in attachment functions and shape changes

Question 17

integral membrane protein location and function?

Answer 17

span the whole membrane, responsible for transport and communication

Question 18

cytoskeleton function & location

Answer 18

anchors to plasma membrane, can interact with receptors

Question 19

cytoskeleton definiton

Answer 19

interlinking protein filaments present in the cytoplasm

Question 20

glycocalyx make up & location

Answer 20

an ensemble of carbohydrates attached to lipids and proteins on the extracellular face

Question 21

what happens to the glycocalyx when the cell becomes cancerous?

Answer 21

changes - can change so much to avoid recognition by immune system

Question 22

cholesterol (overall) function

Answer 22

reduces general membrane fluidity and stabilizes its structure

Question 23

too much cholesterol causes membranes to?

Answer 23

lose flexibility

Question 24

functions of plasma membrane proteins

Answer 24

transport, enzyme activity, receptors for signal transduction, intercellular joining, cell-cell recognition, attachment to ECM

Question 25

ECM definiton

Answer 25

extracellular matrix, protein complex outside the cell

Question 26

tight junctions contain

Answer 26

interlocking junctional proteins and space between cells

Question 27

tight junction function

Answer 27

forms continuous seal on cell to precent molecules from passing between cells

Question 28

desmosomes contains

Answer 28

space between cells, plaque, linker proteins, intermediate filament

Question 29

what is the liner proteins in desmosomes?

Answer 29

cadherins

Question 30

what is the intermediate filament made up of in desmosomes?

Answer 30

keratin

Question 31

desmosomes function

Answer 31

bind adjacent cells together to prevent tearing

Question 32

desmosomes can be compared to

Answer 32

Velcro

Question 33

tight junctions have ----- junctions

Answer 33

impermeable

Question 34

desmosomes have ----- junctions

Answer 34

anchoring

Question 35

gap junctions have ------ junctions

Answer 35

communicating

Question 36

gap junction have

Answer 36

space between cells and channels formed by connexons

Question 37

connexins is an assembly of

Answer 37

six proteins

Question 38

gap junctions function

Answer 38

allow ions and small molecules to pass cell to cell

Question 39

for which cells are gap junction important?

Answer 39

heart and embryonic

Question 40

concentration gradient

Answer 40

a difference in concentration (high to low) `

Question 41

simple diffusion

Answer 41

the process where a substance moves through a semipermeable membrane or in a solution without any help from transport proteins

Question 42

osmosis

Answer 42

movement of water molecules from a solution with a high concentration of water molecules and low solute to a solution with a lower concentration of water molecules but more solutes

Question 43

osmosis generally happens when the membrane is impermeable to ---

Answer 43

solutes

Question 44

isotonic solutions in cells

Answer 44

cell size is normal, same water/solute concretion as inside cells - water moves in and out

Question 45

hypertonic solutions in cells

Answer 45

cell shrinks, loses water by osmosis

Question 46

hypertonic - solute/water concentration inside and outside cell

Answer 46

extracellular fluid contains higher concentration of non-penetrating solutes than inside the cell

Question 47

hypotonic - solute/water concentration inside and outside cell

Answer 47

extracellular fluid contains a lower concentration of non-penetrating solutes than intracellularly

Question 48

hypotonic solution cell

Answer 48

cell grows due to intake of water through osmosis - cell can burst

Question 49

transmembrane transport examples

Answer 49

simple diffusion, carrier-mediated facilitated diffusion, channel-mediated facilitated diffusion and osmosis