Structure and tissues in plants

Question 1

What is a tissue

Answer 1

A tissue is group of one or more cell types which carry out specific functions

Question 2

How do we call the structures of plant root and shoot with meristematic properties

Answer 2

Apices
Buds
Meristems

Question 3

What are meristems?

Answer 3

Undifferentiated tissues ,consisting of cells which constantly divide under suitable conditions and produce new cells.

Question 3

Functions of meristems

Answer 3

Help in plant growth

Produce new plant cells which differentiate into new plant tissue

Question 4

Do meristems always divide?

Answer 4

No, meristems do have dormant period

Question 5

Give 8 characteristics of meristems?

Answer 5

Are living
Are isodiametric ( roughly spherical )
Are structurally and functionally undifferentiated 
Have central nucleus 
Have dense cytoplasm 
Have the ability to multiple 
Have thin primary cell wall
Large central vacuole absent

Question 7

Write the location of the following meristematic tissues?
Apical meristems
Lateral meristems
Intercalary meristems

Answer 7

Apical meristems-located at root tips and shoot tips
Lateral meristems- Found laterally in stem and root of the plants
Intercalary meristems- base of the stem of grass, in nodes of grasses and bamboo

Question 8

What is the type of meristems involved in following functions?

1) primary growth of shoot and root ( increases the length of the plant)
2) secondary growth of shoot and root ( increases the circumference of roots and stems )
3) production of secondary xylem and secondary phloem during secondary growth
4) production of tough periderm during secondary growth
6) rapid growth of damaged leaves

Answer 8

1) apical meristems
2) lateral meristems
3) vascular cambium [lateral meristems]
4) cork cambium [ “]
5) intercalary meristems

Question 9

To which direction do cell division occur in primary growth of roots ?

Answer 9

New cells are produced to both sides of the root apical meristems.

Question 10

What are the structures included in the zone of cell division in primary growth of roots?

Answer 10

Root apical meristems and it’s derivative

Question 11

What do the cells produced outwards differentiate into in primary growth of plant?

Answer 11

Differentiate into root cap

Question 12

Name the meristematic tissue found only in monocot plants?

Give the location of this tissue

Answer 12

Intercalary meristems
At the base of leaf blades
Nodes
Stems of bamboo

Question 12

Define primary growth of roots?

Answer 12

Elongation of root due to the activity of primary meristems located on root apex is called primary growth of roots

Question 12

What do the epidermis of root possess?

Answer 12

Root hair for absorbing soil solutions

Do not possess stomata Because roots are underground parts which do not involve in gas exchange

Question 12

What happens to the cells produced inward to the apical meristems in primary growth of roots

Answer 12

Undergo elongation, in the zone of cell elongation
Then cells become specialized in the zone of cell maturation
And finally becomes mature cells

Question 13

What do the epidermis of stem possess?

Answer 13

Stomata for gas exchange.

Question 14

What do the following primary structures in dicot root and stem develop into after secondary growth?

Epidermis

Answer 14

Periderm

Question 15

Root hair

Answer 15

Roots

Question 16

Stomata

Answer 16

Lenticels

Question 17

Pericycle in root

Answer 17

Lateral roots

Question 18

Pericycle in stem

Answer 18

Lateral shoot

Question 19

What do the following primary structures in shoots develop into after secondary growth?

Leaf primodia

Answer 19

Leaves

Question 20

To which direction do cell division occur in primary growth of shoot?

Answer 20

Only towards the stem.

reason : they do not need a cover to protect them from sunlight because leaf primordia acts as a cover

Question 21

To which direction do primary growth of roots occur in plants?

Answer 21

Cell are produced both outwards and inwards to the apical meristems.

Question 22

Name three tissue systems in plants?

Answer 22

Dermal tissue system Ground tissue system Vascular tissue system

Question 23

Give an example for dermal tissue before and after secondary growth

Answer 23

Before : epidermis | After: periderm

Question 24

Name 3 specialized cells found in the epidermis?

Answer 24

Guard cells ,trichomes, root hair

Question 25

Give 5 features of epidermis?

Answer 25

Protective outer covering of stems and roots in plant body and leaves Tightly packed cells without intercellular spaces A single cell layer tissue Epidermal coating in aerial parts are covered by cuticle Has specialized cells in them.

Question 26

Give functions of epidermis?

Answer 26

Defense against physical damage and pathogens Cuticle helps to prevent water loss Root hairs involve in absorption of water and mineral Guard cells help in gaseous exchange Trichomes ( hairs and glands ) Hairs reduce water loss, shiny hairs reflect excess light Trichomes secrete chemicals involves in defense against insects, pathogens and herbivores.

Question 27

Name two types of ground tissues?

Answer 27

Pith ( inner to vascular tissue) | Cortex ( outer to vascular tissue )

Question 28

Name three main types of cells in ground tissue?

Answer 28

Parenchyma cells Collenchyma cells Sclerenchyma cells

Question 29

Name four main types of functions carried out by ground tissues?

Answer 29

Storage Photosynthesis Support Short distance transport

Question 30

Give 5 features of parenchyma cells

Answer 30

Living at functional maturity Mature cells have relatively thin and flexible primary cell wall ( most cells lack secondary cell wall ) Cell wall has a uniform thickness without any lignification or suberisation Have a large central vacuole Plasmodesmata are present between neighboring cells Has intracellular spaces

Question 31

Give five functions of Parenchyma cells?

Answer 31

Perform metabolic functions (photosynthesis) [ as they are living ] Storage [ stems and roots contain plastids, leucoplast to store starch] Wound repair [ as they have the ability to divide and differentiate] Used in tissue culture practice [ As they have the ability to divide and differentiate] Provide mechanical support [ turgidity in vacuoles]

Question 32

Define primary growth of shoot

Answer 32

Elongation of shoot as result of the activity of primary meristems located in the shoot apex is called primary growth of shoot

Question 33

Give six features of Collenchyma cells?

Answer 33

Living at functional maturity generally elongated Have a thicker flexible primary cell wall Cell wall is unevenly thickened at the corners of the cell only by cellulose. Lignification or suberization is absent. Plasmodesmata are present between adjoining cells Usually intercellular spaces are absent

Question 34

Function of collenchyma cells

Answer 34

Give mechanical support to the stem and leaf without restraining growth. [ cell wall has thicker primary cell wall hence it provides support, cell wall is flexible without lignification or suberization therefore do not restrain the growth]

Question 35

Give 4 features of sclerenchyma cells

Answer 35

Secondary cell walls are produced after cell elongation Secondary cell walls are thickened by large amounts of lignin They are dead at functional maturity Plasmodesmata are absent Plasmodesmata Are absent

Question 36

Name two types of sclerenchyma cells?

Answer 36

Trachieds and fibers

Question 37

Function of sclerenchyma cells

Answer 37

These cells are specialized to provide support and strength

Question 40

What are the locations where we can find collenchyma cells

Answer 40

In young stems and petioles strands of collenchyma cells are found just below their epidermis Found in veins of dicot leaves

Question 40

Where can we find epidermis in plants

Answer 40

In stems and root in primary plant body | In leaves of all plants

Question 40

State the parenchyma cells perform photosynthesis

Answer 40

Palisade and spongy mesophyll

Question 40

State the parenchyma cells which stores starch

Answer 40

Cells in roots and stem which contain plastids(leucoplast) in them

Question 40

Locations where parenchyma cells are found

Answer 40

Mesophyll cells found in leaves and young stems Fleshy part of fruit and seed (endosperm) Pith and cortex of root and stem

Question 41

Locations where sclerenchyma cells are found

Answer 41

Nut shells Coconut shell Fibers