Ib bio 9.1+9.2

Question 1

What are the functions of sieve tubes in the phloem?

Question 2

What is the primary role of the xylem vs the phloem?

Answer 2

Xylem: carries water and dissolved minerals UP the plant
Phloem: carries sugars from the place they are produced to the place they are stored (multidirectional/ all directions)

Question 3

What is lignins function in a plant?

Answer 3

-substance that helps strengthen cell walls in xylem

Question 4

Why doesnt a xylem contain a cytoplasm?

Answer 4

-makes a larger lumen so more water can transport easier

Question 5

Xylem passive or active transport?

Answer 5

Passive

Question 6

When does osmosis occur in the roots of a plant?

Answer 6

-when water absorbed by root cells and solute conc inside root cell in greater than the water in the soil

Question 7

How does water go up the xylem passively?

Answer 7

-capillary action combined with forced of adhesion and cohesion

Question 8

Explain hydrostatic pressure

Answer 8

-organic molecules like sugars and amino acids that go into the phloem
-results in water conc decrease
-water then diffuses to phloem from xylem to balance out conc
-when phloem gets to sink t releases sugars and other organic molecules

Question 9

Translocation

Answer 9

-source of production and is transported via the phloem to sink for storage
-(source to sink)

Question 10

Phloem loading

Answer 10

-active transport use to load organic comps to serve tubes

Question 11

What are cell walls made of

Answer 11

-lignin
-cellulose

Question 12

What is turgor pressure?

Answer 12

-the pressure of the guard cells opening and closing in the stomata

Question 13

What do gaurd cells look like when closed?

Answer 13

Shrunken

Question 14

What do guard cells look like when stomata open?

Answer 14

Swollen

Question 15

What happens in the stomata when there is type presence of light?

Answer 15

-atp powered membrane protein pumps actively potassium in the cell
-causes osmosis

Question 16

What happens to potassium ions in cell when stomata closes?

Answer 16

-water also leaves the cell

Question 17

What is the zone of maturation?

Answer 17

-where cells become functional apart of the plant

Question 18

3 ways mineral ions get into the plant

Answer 18

1) diffusion from soil to root
2) fungal hyphae
3) active transport when higher conc in root than soil

Question 19

What will happen to the plant if water increases? Transpiration

Answer 19

-transpiration will increase

Question 20

What will happen to plant if water decreases? Stomata

Answer 20

-low water intake from roots causes stomata to close and transpiration to slow/ stop

Question 21

What will happen to plant if co2 increased? Transpiration

Answer 21

-transpiration decreases

Question 22

What will happen to plant if c02 increases? Stomata

Answer 22

-cuased stomata to close

Question 23

Xerophyte vs halophyte

Answer 23

Xerophyte
-plants that are well adapted to survive in dry climates
-cacti, succulents

Halophyte
-plants that are well adapted to survive in water with high levels of salt
-marsh grass