Animal Tissues

Question 1

What are the four main type of tissues in the body

Answer 1

Epithelial
Connective tissues
Muscle tissues
Nervous tissues

Question 2

Define tissues

Answer 2

Group of cells that work together to perform specific function/set of functions

Question 3

Epithelial tissues uses and examples

Answer 3

Covers and lines free surfaces in the body
Such as -skin
Cavities of the respiratory and digestive systems
Blood vessels
Heart chambers and walls of organs

Question 4

What are the characteristics of epithelial tissues

Answer 4

• made up almost entirely of cells
• cells are very close and form continuous sheets.
• Adjacent cells are bound together by lateral contacts , such as tight junctions and desmosomes
• no blood vessels, cells receive nutrients by diffusion by tissue fluid in the underlying connective tissue
• some have smooth surfaces, some have projections -cilia or microvilli
• have short cycles- divide up to two or three times a day to replace worn/damaged tissue

Question 5

What is epithelial tissue specialised for?

Answer 5

Carrying out its function of protection , absorption, filtration , excretion and secretion

Question 6

Connective tissue

Answer 6

Consists of non-living extra cellular matrix containing proteins (collagen and elastin )
And polysaccharides (such as hyaluronic acid which traps water
The matrix separates in living cells within tissue and enables it to withstand forces such as weight

Question 7

Give six examples of connective tissue

Answer 7

Blood
Bone
Cartilage 
Tendons
Skin
Ligaments

Question 8

What are chondroblasts

Answer 8

Immature cells in cartilage

Question 9

Explain how chondroblasts turn into Chondrichthyes

Answer 9

They can divide by mitosis and secrete the extra cellular matrix.
Once the matrix has been synthesised the chondroblasts become mature, less active Chondrichthyes , which maintain the matrix

Question 10

What are the three main type of cartilage

Answer 10

-hyaline
Fibrous
-elastic

Question 11

Hyaline cartilage

Answer 11

-form the embryonic skeleton , covers the ends of long bones in adults joins ribs to sternum and is found in the nose, trachea and larynx

Question 12

Fibrous cartilage

Answer 12

Occurs in the discs between the vertebrae in the backbone and knee joint

Question 13

Elastic cartilage

Answer 13

Makes up the outer ear (pinna)

And the epiglottis (flap that covers over the larynx when you swallow)

Question 14

Muscle tissues

Answer 14

Well vascularised
Called fibres-
They are elongated and contain special organelles called myofillaments , these allow muscles to contract

Question 15

Functions of muscle

Answer 15

• allow movement
• skeletal muscle ; packaged by connective tissue sheets, joined to bones by tendons :these muscles hen they contract cause bone to move
• cardiac muscle; makes up the walls of the heart and allows the heart to beat and to pump blood
• smooth muscle ; occurs in the walls of intestine, blood vessels , uterus and urinary tracts, and it propels substances along this tract

Question 16

Epidermal cells

Answer 16

Consists of flattened cells, which lack chloroplasts and form a protective covering over leaves, stems and roots.
Some epidermal cells also have walls impregnated with waxy substance , forming a cuticle.

Question 17

Why are epidermal tissues important to plants that live in dry places?

Answer 17

As the cuticle reduces water loss

Question 18

Vascular tissue

Answer 18

Concerned with transport

Question 19

What are the two types of vascular tissue

Answer 19

Xylem and Phloem

Question 20

What is xylem role

Answer 20

Carry water and minerals from roots to all parts of the plant

Question 21

Phloem vessels role

Answer 21

Sieve tube transfer the products of photosynthesis (mainly from sucrose sugar), in solution, from leaves to parts of the plant that do not photosynthesise , such as roots, flowers, growing shoots

Question 22

What type of cells are contained in meristematic tissue

Answer 22

Stem cells

Question 23

Why are meristematic tissue important

Answer 23

It is from this tissue that all other plant tissue are derived by cell differentiation

Question 24

Where are m tissues found

Answer 24

Roots and shoot tips

In the cambium of vascular bundles

Question 25

The cells in meristems

Answer 25

• have thin walls containing little cellulose
• don’t have chloroplasts
• don’t have large vacuole
• can divide by mitosis

Question 26

Why do mature plants develop a large vacoules and cellulose cell wall?

Answer 26

These prevent the cells from dividing

Question 27

How are xylems derived from meristems

Answer 27

• lignin is deposited in their cell walls to reinforce and waterproof them :however this also kills cells
• the ends of the cells break down so that xylems forms continuous columns with wide lumens to carry water and dissolved minerals

Question 28

Phloem sieves from meristems

Answer 28

Sieve tubes lost most of their organelles, and sieve plates develop between them

Question 29

Companion cells from meristems

Answer 29

Companion cells retain their organelles and continue metabolic functions to provide ATP for active loading of sugars into the sieve tubes

Question 30

List al the plant organs

Answer 30

Leaf
Root
Stem
Flower

Question 31

Leafs function as a plant organ

Answer 31

-photosynthesis

Question 32

Roots function as a plant organ

Answer 32

• anchorage in soil
• absorption of mineral ions and water
• storage ,e.g carrot roots store carbohydrates

Question 33

Stems function as plant organs

Answer 33

• support
• holds up leaves for more sun exposure
• transportation of water and minerals
• transportation of photosynthesis products
• storage of products of photosynthesis

Question 34

Flowers unctions as plant organs

Answer 34

-sexual reproduction

Question 35

Organ definition

Answer 35

A collection of tissues working together to perform the same function is called an organ

Question 36

Tissue definition

Answer 36

Group of cels that work together to perform a specific set of functions