unit 2 cont.

Question 1

morphology of plants

Answer 1

shoot and root systems
vascular tissues

Question 2

shoot system

Answer 2

• consists of stems, leaves, and flowers with internal pipelines for conduction
• stems are frameworks for upright growth and display of flowers
  leaves have photosynthetic cells
  flowers are displayed to attract pollinators

Question 3

roots functions

Answer 3

anchoring the plant
absorbing minerals and water
often storing organic nutrients

Question 4

stomata

Answer 4

on underside of epidermis
small pores flanked by guard cells (open/close)
allow CO2 exchange between the air and the photosynthetic cells in a leaf
also lose water

Question 5

epidermal tissue

Answer 5

stomata is found in epidermis
each stoma is made up of two guard cells that enclose a pore called a stomata pore

Question 6

ground tissue

Answer 6

site of photosynthesis

Question 7

vascular tissue

Answer 7

veins
xylem and phloem
supply mesophyll with water and nutrients
move sugars to rest of plant

Question 8

steps of transport in plants

Answer 8

1. roots absorb water and dissolved minerals from soil
2. water and minerals are transported upward from roots to shoots as xylem sap
3. transpiration, the loss of water from leaves (mostly from stomata)
4. through stomata, leaves take in CO2 and expel O2. the CO2 provides carbon for photosynthesis. Some O2 produced by photosynthesis is used in cellular respiration
5. sugars are produced by photosynthesis
6. sugars are transported as phloem sap to roots and other parts of the plant
7. roots exchange gases with the air spaces of soil, taking in O2 and discharging CO2.

Question 9

osmosis

Answer 9

allows for uptake of water across cell membranes

Question 10

proton pumps

Answer 10

create a hydrogen ion gradient that is a form of potential energy that can be harnessed to do work
contribute to a voltage known as membrane potential

Question 11

how do proton pumps

Answer 11

plant cells use energy stored in the proton gradient and membrane potential to drive the transport of many different solutes

Question 12

water potential

Answer 12

a measurement that combines the affects of solute concentration and pressure
- determines direction of water
water flows from regions of high water potential to regions of low water potential

Question 13

how does solute affect water potential

Answer 13

addition of solutes reduces water potential

Question 14

aquaporins

Answer 14

transport proteins in the cell membrane that allow the passage of water
increase rate of water movement

Question 15

how does water travel up the roots

Answer 15

water enters plant through the epidermis of roots and flow through the xylem
- plants lose an enormous amount of water through transpiration, and transpired water must be replaced by water transported up from the roots

Question 16

root pressure

Answer 16

upward push of xylem sap

Question 17

stomata closing

Answer 17

potassium ions move out of the vacuole and out of the cells, and water potential in cell increases. Water moves out of the vacuoles, following potassium ions
the guard cells shrink in size and the stomata closes

Question 18

stomata opening

Answer 18

potassium ions move into the vacuoles, water potential decreases. Water moves into the vacuoles, following potassium ions
the guard cells expand and the stomata opens

Question 19

guard cells

Answer 19

cells that surround the stomata
^ open and close the stomata
allows CO2 to enter for photosynthesis and releases O2

Question 20

How does K+ enter the cell and leave

Answer 20

using the proton pump
- guard cells pump protons out (when activated by light)
when H+ leaves out the cell, electrochemical gradient is created which drives K+ into the cell, where it accumulates
increase in internal K+ changes solute potential driving water in and increasing turn or

Question 21

factors influencing guard cell

Answer 21

light - stomata generally closed at night, preventing unnecessary water loss when too dark for photosynthesis
- uptake of potassium ions - changes potassium ions
- Level of CO2 in leaf air space
Internal clock

Question 22

how does level of CO2 in leaf air space affect guard cell movement

Answer 22

less CO2 opens the stomata

Question 23

how does internal clock influence guard cell

Answer 23

daily rhythm due to regulation of cell preocesses in eukaryotic cells