Chapter 8: Plant Systems: Gas Exchange and Transport Systems

Question 1

What does vascular mean?

Answer 1

De scribes vessels that conduct fluid

Question 2

What is the epidermis on a plant?

Answer 2

The surface layer of cells in an organism

Question 3

What are stomata?

Answer 3

A controlled opening found in leaves and young stems that controls the movement of gases into and out of a plant

Question 4

What are guard cells?

Answer 4

A pair of crescent-shaped cells that enable the opening and closing of stomata

Question 5

What conditions cause stomata to open?

Answer 5

In wet conditions, the guard cells swell and become rigid, opening the stomata

Question 6

What conditions cause the stomata to close?

Answer 6

Dry conditions, the guard cells lose water they become soft and fall closed, due to this, gases cannot enter and leave

Question 7

What do pineapples, cacti and orchids do to enable photosynthesis, even when the stomata are closed?

Answer 7

They open their stomata during the cool evening and store carbon dioxcide

Question 8

What is mesophyll?

Answer 8

A chloroplast-containing cell in plant leaves that performs photosynthesis

Question 9

What does tugidity?

Answer 9

The state of being swollen with water, which usually causes the cell to become rigid

Question 10

What is the cuticle?

Answer 10

A thin, transparent layer of wax on the outside of a leaf’s epidermis to reduce water loss

Question 11

What are the two types of mesophyll cells?

Answer 11

Palisade mesophyll and spongy mesophyll

Question 12

What is palisade mesophyll?

Answer 12

A densely packed layer of elongated cells that have many chloroplasts for photosynthesis

Question 13

What is spongy mesophyll?

Answer 13

A loosely arranged layer of irregularly shaped cells that have a few chloroplasts for photosynthesis and plenty of air spaces

Question 14

What are the two type of vascular tissues in a plant?

Answer 14

Xylem and phloem

Question 15

What is xylem?

Answer 15

The vascular tissue in plants, consisting of dead cells, responsible for the bulk transport of water and nutrients

Question 16

What is phloem?

Answer 16

The vascular tissue in plants, consisting of living cells, responsible for the transport of sugars from leaves to the rest of the plant

Question 17

What are the two types of cells that make up xylem in a plant?

Answer 17

Tracheids and vessel elements

Question 18

What are tracheids?

Answer 18

A dead elongated cell that forms, the unspecialised part of the xylem of plants

Question 19

What are vessel elements?

Answer 19

A dead cell that is perforated at each end and stacked vertically, forming the specialised part of the xylem in flowering plants, almost a straw

Question 20

Which is more effective: tracheids or vessel elements?

Answer 20

Vessel elements due to their ‘straw like’ strucutre, however, this adaptation is only foun din flowering plants (angiosperms)

Question 21

What are the two types of phloem cells?

Answer 21

Sieve tube cells and companion cells

Question 22

What is a seive tube cell?

Answer 22

A long, tubular plant cell without a nucleus that form seive tubes, the main component of the phloem

Question 23

What is a companion cell?

Answer 23

A specialised plant cell situated beside the seive tubes in the phloem, which provides most of the cell dunctions for the seive tube cells

Question 24

What are sieve plates?

Answer 24

The tough cellulose walls between sieve tube cells that contain pores to allow the cytoplasm to flow between cells

Question 25

What are plasmodesmata?

Answer 25

A tiny channel through plant cell walls that allows communication between cells by sharing cytoplasm

Question 26

What are the two main root forms?

Answer 26

Taproot and fibrous root

Question 27

What is a taproot?

Answer 27

A large main root deep underground for stability and long-term water supply

Question 28

What is a fibrous root?

Answer 28

A thin, branching root that spreads along the upper layers of soil for rapid colonisation and surface water uptake

Question 29

What is root hair?

Answer 29

A thin extension of a root epidermal cell that greatly increases the cell’s surface area

Question 30

What is root pressure?

Answer 30

The prussure, caused by the uptake of water in the roots, that forces water furhter up the stem

Question 31

What are monocotyledons (monocots)?

Answer 31

A flowering plant with a number of characteristics, including scattered arrangement of vascular bundles in the stem

Question 32

What are dicotyledons (dicots)?

Answer 32

A flowering plant with a number characteristics, including a ringed arrangement of vascular bundles in the stem

Question 33

What is adhesion?

Answer 33

The force of attraction between water molecules and the molecules that make up the sides of the tube

Question 34

What is cohesion?

Answer 34

The force of attraction between water molecules

Question 35

What is transpiration?

Answer 35

The loss of water from plants through evaporation

Question 36

What is transpiration stream?

Answer 36

A continuous column of water that moves up the stem of the plant

Question 37

What is transpirational pull?

Answer 37

The force arising from the evaporation of water from leaves that draws water up the xylem

Question 38

What factors can increase the rate of transpiration?

Answer 38

High air temperatures, low humidity, wind and long days with strong sunlight

Question 39

What are some adaptations to reduce water loss?

Answer 39

Thick waxy leaves, minimal stomata, spines

Question 40

What factors can decrease the rate of transpiration?

Answer 40

Low air temperatures, high humdity, stifled airflow and short days with weak sunlight

Question 41

What is translocation?

Answer 41

The bulk movement of substances during metabolic reactions