bio quiz 3

Question 1

what is homeostasis

Answer 1

steady, internal physical and chemical conditions maintained by living systems

Question 2

what kind of system is a cell

Answer 2

open system because it can exchange matter and energy with its surroundings

Question 3

What is passive transport

Answer 3

passive transport is the movement of substances with the conectraion gradient (from high to low)
does not require energy (ATP)

Question 4

What is simple diffusion

Answer 4

movement of solute from high to low concentration across membranes bilayer
membrane must be permeable to solute
no transport proteins required (right through mem)

Question 5

What is facilitated diffusion

Answer 5

high to low concentration with help of channel proteins
membrane is impermeable to solute because of its large size

Question 6

What is osmosis

Answer 6

movement of water across semi-permeable membrane high water concentrate to a low one
water always moves naturally to where there are more solutes
mem doesn’t allow solute but water does
if membrane is not permeable then their will be a net movement of water
\water always moves to more solutes so hypotonic to hypertonic

Question 7

What is hypertonic

Answer 7

solution with lots of solutes compared to another solution

Question 8

hypotonic

Answer 8

little solutes compared to another solution

Question 9

isotonic

Answer 9

a solution that has equal solutes to another solution

Question 10

Why would a cell shrivel

Answer 10

because the ECF has a high concentration of solutes than the cytoplasm there will be a net movement of water from cytoplasm to ECF
hypo—> hyper

Question 11

Why does a cell expand

Answer 11

cytoplasm has higher concentration of solutes then ECF there will be a net movement of water from ECF to cytoplasm
hypo on outside hyper on inside

Question 12

What is plasmolysis

Answer 12

when plant cell is placed in solution with higher solute concentration than the cell the vacuole loses water and shrinks causing cell membrane to peel away from cell wall, this causes the plant to wilt or go limp

Question 13

What does it mean when something has high turgor pressure

Answer 13

placed in a solution with a lower solute concentration the vacuole gains water and swells cell membrane pushes up against cell wall
it is the cell wall maintaining turgor pressure
you cant talk about turgor pressure for animal cells since they do not have cell walls

Question 14

What is hemolysis

Answer 14

exploding / causing red blood cells to burst

Question 15

what is crentation

Answer 15

shrinking due to osmosis water loss

Question 16

what is active transport

Answer 16

movement of particles from area of low concentration to high concentration (going against concentration gradient)
requires energy
helps maintain internal environment different from external

Question 17

Explain active transport using carrier protien

Answer 17

requires ATP because moving against concentration gradient
atp also required to alter shape of carrier protein
used for smaller substances

Question 18

explain active transport using vesicle

Answer 18

membrane changes in order to form vesicles
vesicles carry substances in or out of the call against concentration gradient
used for large substances ONLY not small molecules

Question 19

What us Endocytosis

Answer 19

cell surounds and takes in large substcanecs from environment
substance does not pass directly through membrane
substance forms on the outside of cell and cell membrane “dips” inward to form the beginning of a vesicle
vesicle engulfs subatnce and begins moving contents around cell

Question 20

What is Phagocytosis

Answer 20

cell eats large chucks of materials
food or solids taken in

Question 21

What is Pinocytisis

Answer 21

cell drinks lots of small materials, drops of fluid taken in
ions would not move across membrane in this manner

Question 22

What is Exocytosis

Answer 22

release of large materials from cell
expels materials stored in vesicles and vacuolds by fusing cell membrane
used to get rid of waste

Question 23

Why is cell size important

Answer 23

It is the most efficent to have a high surface area to low volume ratio because it takes less energy to move materials in and out of the cell closer the membrane to other parts the more efficient
think of pool vs lake analogy
diffusion is slow and inefficient over long distances especially within cell