Plant cells & tissues

Question 1

What parts are plants organised into? In order from least complex to most complex.

Answer 1

Cells - individual compartments
Tissues - A group of cells with a similar structure & function work together to do a particular job. eg. meristematic tissue.
Organs - A group of tissues which work together to do a particular job. eg. leaf.
Organisms - A group of organs which work together. eg. Rose plant.

Question 2

What are the two primary differences between a plant cell and an animal cell?

Answer 2

Produce their own food.

Support their own weight.

Question 3

How does a plant cell differ from an animal cell?

Answer 3

Plant cells contain choloroplasts for photosynthesis. Animal cells do not.
Plant cells are surrounded by a strong cellulose wall to prevent the cell bursting due to the pressure of water inside and to give the plant strength. Animal cells do not have a cell wall.

Question 4

What are the 7 parts of the plant cell?

Answer 4

Cell wall
Cell membrane
Vacuole
Nucleus
Mitochondria
Chloroplasts
Cytoplasm

Question 5

What is the function of the cell wall.

Answer 5

Provides support for the plant as it is rigid and strong.
Allows the cell to become turgid as it will expand but remain intact as water enters the cell by osmosis.
Separates one cell from another.

Question 6

What is the function of the cell membrane?

Answer 6

Controls the movement of substances into and out of the cells. Semi permeable. Water can pass through it by diffusion but other solutes cannot. Osmosis and Active transport both happen here.

Question 7

What is the function of the nucleus?

Answer 7

The nucleus is the brain of the cell - controls all the activities within the cell. Also controls growth. Often to the side of a plant cell.

Question 8

What is the function of the Cytoplasm?

Answer 8

Jelly like substance in which the organelles are suspended. Helps to give the cell it’s shape along with the vacuole.

Question 9

What is the function of the Vacuole?

Answer 9

Large fluid filled sac which creates internal pressure and pushes cytoplasm to the internal edge of the cell. Helps maintain cell shape. Contains mineral salts, sugars and waste pigments. Storage mechanism - can store waste products and pigments.

Question 10

What is the function of the Chloroplast?

Answer 10

Organelle containing chlorophyll. Series of stacked discs to increase surface area. Chloroplasts absorb light and use the energy to make sugars from Co2 and water. Photosynthesis. Large numbers in leaf cells, and not in root cells. Also found in young

Question 11

What is the function of the Mitochondria?

Answer 11

Sausage shaped organelle. Site of cellular respiration where stored sugars are broken down to release energy om the form of ATP Lots of energy used when cells are dividing so there are many mitochondria in meristem tissue. Energy used for active transport of large molecules across cell membrane.

Question 12

What is packing tissue called?

Answer 12

Parenchyma or Cortex

Situated between the vascular tissue and the epidermal tissue.

Question 13

What is transport tissue called?

Answer 13

Phloem and Xylem - transports sugars and waters and nutrients.
Xylem = water & minerals
Phloem = sap with dissolved nutrients & minerals.

Question 14

What is protective tissue called?

Answer 14

Epidermis - protects the outside of the plant.

Question 15

What are the characteristics of Parenchyma tissue?

Answer 15

Packing tissue. Can be in the spongy mesophyll or the palisade mesophyll or cortex or pith.
Large round shape.
Large vacuole.
Contains many chloroplasts in leaf.
Thin cell wall.
May contain starch grains (storage in root for example)

Question 16

What are the characteristics of epidermis tissue?

Answer 16

Found in the root, stem & leaf.
Tightly packed cells.
No spaces between to protect from predators like aphids.
Transparent.
Waxy surface area - the cuticle on leaves & stem.
May be elongated to form a trichome which has a special function. eg. root hair or leaf hair.

Question 17

What are the characteristics of Xylem tissue?

Answer 17

Xylem vessels and tracheids.
Dead cells at maturity, with no cross cells to make a hollow tube.
Cell walls contain lignin for structural support.
Transports water & minerals in both directions.

Question 18

What are the characteristics of Phloem tissue?

Answer 18

Sieve cells which are living cells and have a perforated wall to form a tube and no nuclei.
Companion cells have many mitochondria to provide energy for movement of phloem and support the sieve cells.

Question 19

What are the characteristics of meristematic tissue?

Answer 19

Apical meristem situated in the apical bud and root tip.
Also in the vascular cambium in root and stem.
Cells are tightly packed as divide rapidly.
Large nucleus.
Many mitochondria providing energy.
No vacuole.
Undifferentiated.

Question 20

What is a cluster of xylem, phloem and cambium called?

Answer 20

Vascular bundle

Question 21

What does a plant cells need to do to so the plant can grow?

Answer 21

Multiply in number
Enlarge - expansion.
Multiply in numbers - cell division.

Question 22

Where does plant cell division take place?

Answer 22

In the meristematic tissue.

Question 23

What does Vascular Cambium do?

Answer 23

Gives rise to new Xylem and Phloem cells increasing girth of plant by secondary growth.

Question 24

Do Monocotyledons get woody?

Answer 24

No. Think grasses, daffordils. Doesn’t get a wider girth. Therefore does not have a vascular cambium.

Question 25

Do Dicotolyedons get woody?

Answer 25

Yes. Think trees, shrubs, herbaceous perennials. They do get wider, therefore does have a vascular cambium.

Question 26

What is a lateral meristem?

Answer 26

Found only in Dicotyledons. Known as the Vascular Cambium. Found in stem and roots. That’s why you can do cuttings easily of dicotyledons.

Question 27

What happens in the meristems?

Answer 27

Multiplication of cells through division called MITOSIS.