chapter 3 ppt

Question 1

what are phospholipids?

Answer 1

the major lipid component of cellular membranes

Question 2

what does a phospholipid molecule consist of?

Answer 2

polar phosphate head that is hydrophilic and a non-polar lipid tail that is hydrophobic

Question 3

what do unsaturated fatty acids result in?

Answer 3

kinks in hydrophobic tails

Question 4

what does the phospholipid bilayer consist of?

Answer 4

two adjacent sheets of phospholipids, arranged tail to tail

Question 5

structure of the phospholipid bilayer

Answer 5

tails form interior, polar head contact fluid outside of the cell

Question 6

what molecular components does the cell membrane have

Answer 6

proteins, cholesterol, and some carbohydrate groups

Question 7

the membrane is ________ permeable to ______ and ________

Answer 7

selectively; ions; molecules

Question 8

4 ways molecules cross biological membranes

Answer 8

simple diffusion, facilitated diffusion, osmosis, active transport

Question 9

simple diffusion

Answer 9

lipid bilayer allows only small, non-polar substances like oxygen and carbon dioxide to pass through the cell membrane; downs the concentration gradient

Question 10

facilitated diffusion

Answer 10

• takes place with help of channel and carrier proteins
  *channel proteins are less selective and discriminate because of size and charge
  *carrier proteins are more selective, only allows one type of molecule to cross

Question 11

osmosis

Answer 11

*diffusion of water through a semipermeable membrane
* if a membrane is permeable to water and not to a solute, water will equalize its concentration by diffusing to the side of lower water concentration

Question 12

hypertonic

Answer 12

solution has a solute concentration higher than another solution

Question 13

isotonic

Answer 13

solution has a solute concentration equal to another solution

Question 14

hypotonic

Answer 14

solution has a solution concentration lower than another solution

Question 15

active transport

Answer 15

• sodium potassium pump
• powered by ATP, three sodium ions go out and two potassium ions go into the cell

Question 16

what is endocytosis

Answer 16

form of active transport where a cell envelopes extracellular matrix materials using it’s cell membrane

Question 17

3 types of endocytosis

Answer 17

phagocytosis, pinocytosis, receptor- mediated endocytosis

Question 18

phagocytosis

Answer 18

nonselective, cell takes in a large particle

Question 19

pinocytosis

Answer 19

cell takes in small particles in fluid

Question 20

exocytosis

Answer 20

material is packed into vesicles, vesicles membrane attaches to cell membrane and exports the material

Question 21

exocytosis examples

Answer 21

neurotransmitters, digestive enzymes

Question 22

what do pancreatic acinar cells secrete

Answer 22

enzymes that digest food

Question 23

what is the ER

Answer 23

winding network of thin membranous sacs, close to the nucleus

Question 24

rough er

Answer 24

studded with ribosomes, site of protein synthesis

Question 25

smooth er

Answer 25

synthesizes phospholipids, regulates concentration, breaks down toxins

Question 26

golgi apparatus

Answer 26

*creates lysosomes
* organizes, modifies, packages, and tags products of the ER

Question 27

mitochondrion

Answer 27

• energy- conversion factory
• two lipid bilayer membranes
• produces ATP

Question 28

peroxisome

Answer 28

• membrane bound organelles
• detoxifies harmful substances

Question 29

3 components of the cytoskeleton

Answer 29

microtubules, microfilaments, intermediate filaments

Question 30

cytoskeleton

Answer 30

• maintains cell shape
• aides cell division

Question 31

nucleus

Answer 31

• control center
• contains genetic material

Question 32

multinucleated

Answer 32

contains many nuclei

Question 33

erythroblasts

Answer 33

extrude red blood cell’s nucleus

Question 34

stem cells

Answer 34

replace damaged cells of different body tissues