Lecture 4: Tissues (II)

Question 1

Draw a root tip, showing the root cap and three zones.

Answer 1

Draw on a piece of paper

Question 2

Draw a cross-section of a dicot root, showing the epidermis, cortex, endodermis, pericycle, xylem and phloem.

Answer 2

Draw on a piece of paper

Question 3

Draw a cross section of a herbaceous dicot stem, showing the epidermis, cortex, pith, bundle cap, xylem, phloem, and vascular cambium.

Answer 3

Draw on a piece of paper

Question 4

Draw a cross section of a woody stem, showing the bark, (cork, cork cambium, cortex, phloem), vascular cambium, xylem and pith.

Answer 4

Draw on a piece of paper

Question 5

Draw a cross section of a leaf, showing the upper and lower epidermis, palisade mesophyll, spongy mesophyll, xylem and phloem.

Answer 5

Draw on a piece of paper.

Question 6

What are the 3 zones on a longitudinal cross of a root tip?

Answer 6

Zone of cell division
Zone of cell elongation
Zone of maturation

Question 7

What does the root cap do?

Answer 7

Protect the apical meristem

Question 8

What does the zone of cell division do?

Answer 8

The apical meristems multiply to elongate the stem

Question 9

What does the zone of cell elongation do?

Answer 9

Vacuoles fill with water and the cells stretch and lengthen.

Question 10

What does the zone of maturation do?

Answer 10

Cells differentiate (specialise) and form tissues.

Question 11

What tissues are formed at the zone of maturation of a root tip?

Answer 11

Xylem and phloem.

Question 12

What also grows from the epidermis of a root tip?

Answer 12

Root hairs.

Question 13

What are the four parts of a dicot root cross section?

Answer 13

Epidermis
Cortex
Endodermis
Vascular cylinder

Question 14

What does the epidermis of a dicot root do?

Answer 14

Outer layer of the root involved in the absorption of water and minerals.

Question 15

What does the cortex of a dicot root cross section do?

Answer 15

A big section of the root that stores starch

Question 16

What is located in the innermost layer of the cortical cell?

Answer 16

Endodermis

Question 17

What does the endodermis of dicot roots do?

Answer 17

Allows water and nutrients to pass through endodermal cells to enter the vascular cylinder.

An inner layer of cells in the cortex of a root and some stems, surrounding a vascular bundle.

Question 18

Where is the Casparian strip located?

Answer 18

Lies around the endodermal cells

Question 19

What does the Casparian strip in the dicot root do?

Answer 19

Prevents passage between dermal cells and is waterproof

Question 20

What is the vascular cylinder and what does it do?

Answer 20

Vascular cylinders are the core of plant stems and roots. They have the crucial job of ensuring that key nutrients, water, and other substances are transported throughout the plant.

Xylem and phloem are found inside.

Question 21

What is a pericycle in dicot roots?

Answer 21

Type of meristem that produces lateral roots inside the endodermis.

Question 22

What is the epidermis in herbaceous dicot stems?

Answer 22

Outermost layer of cells providing protection for the interior of the stem

Question 23

What is the cortex of herbaceous dicot stems?

Answer 23

Small layer of cells under the epidermis which add strength to the stem.

Question 24

What may exist in the cortex of herbaceous dicot cells?

Answer 24

Chloroplast

Question 25

What is the pith of herbaceous dicot stems?

Answer 25

Centre of the stem

Question 26

What is a vascular bundle in dicot stem cross section?

Answer 26

It forms the circle pattern in the dicot stem and contains both xylem and phloem tissues (transports food and nutrients)

Question 27

What is the bundle cap in herbaceous dicot stems?

Answer 27

It provides support to the stem and is comprised of sclerenchyma cells which form fibres and provides support

Question 28

Where is the vascular cambium located in herbaceous dicot stems?

Answer 28

Between the xylem and phloem

Question 29

What does the vascular cambium do in woody stems?

Answer 29

Produces new xylem on the inside and new phloem on the outside and is found in between the xylem and phloem

Question 30

What are the bark layers? How are they layered? List it from inside to the outermost layer.

Answer 30

1. Phloem 2. Cortex 3. Cork cambium 4. Cork

Question 31

Where is the xylem located inside a woody stem?

Answer 31

Inside the vascular cambium

Question 32

Why are larger xylem cells produced in the Spring for woody stems?

Answer 32

More water is needed

Question 33

Why are smaller xylem cells produced in the summer?

Answer 33

Less water is needed

Question 34

What does the upper epidermis of a leaf do?

Answer 34

Provides protection to the leaf

Question 35

What does the cuticle on a leaf do?

Answer 35

Waxy surface that helps reduce water loss

Question 36

What does the lower epidermis do in leaf cells?

Answer 36

Porous surface that contains stomata

Question 37

What do the stomata do?

Answer 37

Allows carbon dioxide in and oxygen out during photosynthesis

Question 38

Where are guard cells located?

Answer 38

Located on both sides of one stoma

Question 39

What do guard cells in leaves do?

Answer 39

Regulate how many stomata exist

Question 40

What is a palisade mesophyll?

Answer 40

Closely packed elongated parenchyma cells that conduct photosynthesis

Question 41

What is spongy mesophyll?

Answer 41

Loosely packed parenchyma cells with intercellular spaces for gases to move in and allow for air to pass through the stomata. Helps with photosynthesis

Question 42

What are vascular bundles in leaves?

Answer 42

Veins in a leaf that contain xylem on the upper half, and phloem on the lower half

Question 43

Where are bundle sheath cells located in leaves?

Answer 43

Surrounding the xylem in leaves

Question 44

What do bundle sheath cells do?

Answer 44

Hold the xylem and phloem together in leaf cells.

Question 45

What is the difference between the cortex in root cells, and cortex in herbaceous stems cells?

Answer 45

Cortex in roots store starch. Cortex in herbaceous stems help strength the stem.

Question 46

What is the difference between the epidermis in root cells and the epidermis in herbaceous stem cells?

Answer 46

The epidermis in root cells help with the absorption of water and nutrients. The epidermis in herbaceous stems provide protection to the stem's interior.