unit 6

Question 1

what is the cell membrane made of?

Answer 1

phospholipid bilayer, proteins, cholesterol

Question 2

what is the model of the cell membrane called?

Answer 2

fluid mosaic model

Question 3

what does the cell membrane control?

Answer 3

controls what goes in/out of the cell, to maintain homeostasis

Question 4

homeostasis–

Answer 4

internal balance needed for survival

Question 5

cell membrane is semi–

Answer 5

permeable or selectively permeable

Question 6

what does semipermeable (or selectively permeable) mean?

Answer 6

it allows only somethings to enter/leave while excluding others. In other words, it selects what enter/leaves. It does not allow everything to enter/leave

Question 7

extracellular–

Answer 7

outside the cell

Question 8

intercellular–

Answer 8

inside the cell

Question 9

how do substances move in and out of the cell?

Answer 9

the size and polarity of the molecule determines whether it can move into a cell

Question 10

can water, O2, CO2, N2, I2 (iodine) pass though the cell membrane?

Answer 10

yes, all those are easy to pass through the cell membrane

Question 11

can large molecules like glucose, amino acids, charged molecules, and sugar get into the cell membrane?

Answer 11

all those examples that cannot easily cross

Question 12

what ways do substances move in and out of the cells?

Answer 12

passive transport and active transport

Question 13

does passive transport need energy (ATP)?

Answer 13

no, molecules do not need energy to move across the cell membrane to move across the cell membrane

Question 14

does active transport need energy (ATP)?

Answer 14

yes, molecules need energy to move across the cell membrane

Question 15

passive transport–

Answer 15

molecules move with the flow, from an area of high concentration to an area of low concentration

Question 16

what are the three types of passive transports?

Answer 16

simple diffusion, facilitated diffusion, osmosis

Question 17

simple diffusion–

Answer 17

the movement of molecules from an area of higher concentration to an area of lower concentration, all molecules are constantly moving in space

Question 18

facilitated diffusion–

Answer 18

the movement of molecules from an area of higher concentration to an area of lower concentration through a protein gate or a channel protein (sometimes called a protein channel)

Question 19

osmosis–

Answer 19

the movement of water through a membrane from an area of high water concentration to an area of low concentration, from more H2O to less H2O (H2 osmosis)

Question 20

true or false: water moves with the concentration gradient

Answer 20

true

Question 21

what happens to cells when you put them in solutions of different concentrations?

Answer 21

osmosis occurs

Question 22

solution = solvent + ???

Answer 22

solute

Question 23

solvent–

Answer 23

water (dissolves stuff)

Question 24

solute–

Answer 24

what is dissolved in water

Question 25

how many types of solutions are there?

Answer 25

3 types

Question 26

what are the three types of solutions?

Answer 26

isotonic, hypertonic, hypotonic

Question 27

isotonic--

Answer 27

same solute concentration as the cell, cell stays the same, water enters and leaves the cell in same amounts

Question 28

hypertonic--

Answer 28

higher solute concentration than the cell, more water leaves the cell, cell shrinks (plasmolysis)

Question 29

hypotonic--

Answer 29

lower solute concentration, more water enters the cell, cell blows up/bursts (swells) (cytolysis)

Question 30

active transport--

Answer 30

requires ATP (energy), molecules move from an area of low concentration to an area of high concentration

Question 31

how many types of active transport are there?

Answer 31

3 types

Question 32

what are the types of active transport?

Answer 32

protein pumps (carrier protein) in the membrane endocytosis (into) extocytosis (exit)

Question 33

protein pumps--

Answer 33

in the membrane (carrier proteins), proteins move large molecules across the membrane from low to high concentration

Question 34

endocytosis--

Answer 34

when cells take in material by making pockets in the cell membrane, the pocket becomes a vacuole

Question 35

exocytosis--

Answer 35

cells send materials out, a vacuole fuses with the membrane and releases the content

Question 36

do endocytosis and exocytosis require energy?

Answer 36

yes

Question 37

what are the two types of endocytosis?

Answer 37

phagocytosis and pinocytosis

Question 38

phagocytosis--

Answer 38

takes in larger substances (bacteria)

Question 39

pinocytosis--

Answer 39

takes in fluids and solutes cell "drinking"