2.1 Plant cells & tissues Flashcards Preview

RHS Level 2 Module R2101 > 2.1 Plant cells & tissues > Flashcards

Flashcards in 2.1 Plant cells & tissues Deck (22)
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1

Function of: Cell Wall

Outer layer - controls shape of the cell

Provides strength and rigidity

Protects against pathogens

2

Function of: Cell Membrane

Located just inside Cell Wall.

Contains and encloses cell contents and produces the cell wall.

Selectively-permeable to control what passes in and out of a cell

3

Function of: Cytoplasm

Jelly-like substance inside the Cell Membrane

Contains most of the organelles, and also dissolved minerals and nutrients

4

Function of: Chloroplasts

Organelles in a cell which trap light energy to conduct photosynthesis.

5

Function of: Mitochondria

Site of respiration

They break down sugars to release energy

6

Function of: Vaculoles

Pockets of water - store minerals, pigments or waste products

Aid in cell expansion and rigidity (turgor)

7

Function of: Endoplasmic Reticulum

Wavy, sheet-like structures that surround the Nucleus

A factory that makes proteins and other structures;

Also makes new cell membranes and hormones

8

Function of: Nucleus

Contains DNA which controls cell processes and metabolism

Initiates cell devision and codes for the characteristics of the plant

9

Function of: Chromosomes

Arranged bodies of DNA within the Nucleus

Contain coded information for the cell.

10

Where is cell division located within a plant?

In the Meristems

Apical meristem is present in shoot and root tips (root apical meristem and shoot apical meristem)

Lateral meristem is present on lateral sides of stems and roots - they increase the girth/thickness of the plant.

Vascular cambium and cork cambium are examples of lateral meristematic tissues

11

How do plants increase in size?

Through cell division (sited at meristems)

Through cell expansion

Differentiation is the third process - when cells modify to perform certain functions

These three combined processes lead to formation of plant tissues.

12

What does the term, "Plant Tissue" mean?

A group of similar cells performing a specific function or purpose

(Many different types of tissues combine to form many different complex organs (e.g. leaves, stems etc))

13

TWO characteristics and TWO functions of: Epidermis

Characteristics:

Outermost layer of tissue with surface wax (cuticle)

May have specialised cells - e.g hairs/guard cells

Functions:

Protection from pests/diseases

Prevention of water loss

Gas exchange

14

TWO characteristics and TWO functions of: Cambium

Characteristics:

Found in stems and roots.

A layer of meristematic cells

Functions:

Forms xylem and phloem;

Allows dicots to become thicker by laying down secondary xylem and phloem.

15

TWO characteristics and TWO functions of: Phloem

Characteristics:

Located in vegetative tissues

Forms part of the vascular tissue.

Functions:

Food transport tubes (sugars/ carbohydrates)

Structural

16

TWO characteristics and TWO functions of: Xylem

Characteristics:

Forms part of the vascular tissue

Formed of dead, tube-shaped cells


Functions:

Water and nutrient transport from roots to leaves;

Forms wood for strength and support

17

TWO characteristics and TWO functions of Parenchyma

Characteristics:

Made from simple cells that are generally rounded;

Has thin cell walls and large vacuoles.

Functions:

"Packing tissue" for maintaining shape through turgor;

May have specialised function - e.g. starch storage

18

Cortex: function and location

Packing tissue in roots and stems

Sits just beneath the epidermis

19

Endodermis: function (1) and location (2)

Controls the uptake of water & dissolved nutrients

Located in roots

Innermost layer of the cortex

Casparian strip also located here

20

Pericycle: function and location

Layer of meristematic cells that produces lateral roots.

Located in roots, between endodermis and vascular tissue - outermost layer of stele.

21

Packing tissue location & characteristics:

E.g. parenchyma and cells in the pith, cortex and mesophyll.

Thin cell walls

Air spaces between cells

Living cell contents

Storage for starch

Contain chloroplasts for photosynthesis

22

Meristematic tissue location and characteristics:

Location: apical meristems of shoots and roots, vascular cambium.

Unspecialised cells

Capable of cell division

Tightly packed together

Small vacuole

Contain numerous mitochondria