Unit 2 - Cell Organelles, Plasma Membrane, Transport

Question 1

Prokaryote characteristics

Answer 1

• no membrane bound nucleus
• circular DNA
• simple
• ribosomes floating in cytoplasm

Question 2

Eukarytoe characteristic

Answer 2

• membrane bound nucleus, structures
• linear DNA
• multicellular: mitochondria/chloroplast, golgi
• bound ribosomes

Question 3

Compartmentalization

Answer 3

local environments for different functions (lysosome has a different pH)

Question 4

Endosymbiosis

Answer 4

1. folding of plasma membrane
2. engulfing of aerobic prokaryote
3. autotrophs diverge from heterotrophs
   
   • autotroph engulfs photosynthetic prokaryote
4. ancestral eukaryotes develop

Question 5

Cell Wall (prokaryote, plant)

Answer 5

plant: cellulose
fungi: chitin
prokaryote: peptidoglycan

help with shape/structure and also protection

Question 6

Plasma membrane (all three)

Answer 6

phospholipid bilayer

help with H2O regulation/pressure, help transport things across the membrane

Question 7

Ribosome (all three)

Answer 7

protein synthesis!

prokaryotes: free in cytosol/cytoplasm
eukaryotes: bound (rough ER)

Question 8

Smooth ER (eukaryotes)

Answer 8

make lipids, detoxification

Question 9

Rough ER (eukaryotes)

Answer 9

ribosomes bound, form protein

Question 10

Golgi (eukaryotes)

Answer 10

modifies, packs, and sorts proteins/materials

cis (close to RER) and trans side (where proteins bud off)

Question 11

Mitochondria (eukaryotes)

Answer 11

double membrane with cristae (inner membrane)
cellular respiration

more mitochondria = more metabolism
more surface area of inner membrane = more rate of exchange, more efficient kreb cycle

Question 12

Lysosome (eukaryotes)

Answer 12

digestion, pH: 5 (acidic), autophagy (recycle cell matter), hydrolyze

Question 13

Nucleus (eukaryotes)

Answer 13

chromosomes, double membrane

Question 14

Peroxisome (eukaryotes)

Answer 14

enzyme that converts peroxide into water

Question 15

Chloroplast (plant only)

Answer 15

photosynthesis

thylakoid (singular disk) and grana (stack of disks): light dependent
stroma (fluid): calvin/dark cycle

Question 16

Vacuole (eukaryotes)

Answer 16

food vacuole: phagocytosis
contractile: maintaining water level
central (plants): turgor pressure

Question 17

Cytoskeleton (eukaryotes)

Answer 17

structural support:
1. microtubules (tubulin): movement of cells, support
2. microfilaments (actin): structure support, shape/tension
3. intermediate filaments (fibrous protein): movement of materials, shape, anchor, cushion

Question 18

Centrioles (animal only)

Answer 18

function during reproduction with spindle fibers

Question 19

Endomembrane system

Answer 19

1. RNA attaches to the ribosome, turns primary structure to polypeptide (mRNA to polypeptide) in the lumen of the RER
2. protein leaves RER in a vesicle and goes into golgi cis side
3. modified and packaged in golgi and leaves in vesicle from trans side (budding off)
4. vesicle is transported to other parts of cell or out of membrane

Question 20

Cell size

Answer 20

increased surface area and colume = increased rate of material exchange

Question 21

Osmoregularity

Answer 21

regulate solute and concentrations to maintain water balance, high to low water potential, low to high solute

Question 22

Hypotonic

Answer 22

hypo: low water inside, high solute
cell gains H2O

plants use this for turgor pressure (vacuole), turgid

Question 23

Hypertonic

Answer 23

hyper: over water inside, low solute
cell loses H2O

plasmolysis

Question 24

Isotonic

Answer 24

dissolved, balanced

Question 25

Phospholipid head

Answer 25

philic, polar

Question 26

Phospholipid tail

Answer 26

phobic, nonpolar

Question 27

What can pass through a phospholipid bilayer without anything?

Answer 27

small, nonpolar N2, O2, CO2, hormones, lipids

Question 28

Integral protein

Answer 28

embedded, amphipathic (part sticking out is philic and part within the membrane is phobic)

Question 29

Peripheral protein

Answer 29

loosely bonded on the surface, philic

Question 30

Glycolipid/protein

Answer 30

cell-to-cell recognition

Question 31

Carrier protein

Answer 31

conformational change glucose, nucleoside, animo acids ions, large, polar

Question 32

Channel protein

Answer 32

tunnel is philic, outside touching membrane is phobic aquaporins (H2O) ions, large, polar

Question 33

Cholesterol

Answer 33

temperature buffer, maintains fluidity inc. temp. = dec. movement dec. temp. = inc. movement

Question 34

Active transport

Answer 34

requires ATP, against concentration gradient (low > high)

Question 35

Sodium Potassium Pump

Answer 35

2 Na+ are pumped out, 3 K+ are pumped in against their concentration gradients through carrier proteins that change when phosphate from ATP is attached creates an electrochemical gradient since more positive on the inside due to net +1 from the K+

Question 36

Cotransport

Answer 36

Lots of H+ on the outside and O wants to move in against it's concentration gradient due to H+ electrochemical gradient, it will flow back in and bring an oxygen with it

Question 37

Symporter

Answer 37

cotransport where both things move in with the same direction

Question 38

Antiporter

Answer 38

cotransport where the action of one moving in/out will move the other one in the opposite way

Question 39

Exocytosis

Answer 39

lysosome digests material and sends it in a vesicle to fuse with the membrane and thrown out (all with the sue of ATP)

Question 40

Phagocytosis

Answer 40

food is engulfed fully by the membrane (food vacuole) which will then fuse with the lysosome

Question 41

Pinocytosis

Answer 41

small molecules engulfed by membrane (protein coated vesicle)

Question 42

Receptor-Mediated

Answer 42

receptors detect specific substances which are engulfed by the membrane and transported

Question 43

Osmosis

Answer 43

diffusion of high H2O to low H2O (or low solute to high solute)

Question 44

Passive transport

Answer 44

with the concentration/electrochemical gradient

Question 45

Diffusion

Answer 45

high to low, selectively permeable membrane (allows for different rates of diffusion for different molecules)