cell organisation

Question 1

what is a tissue

Answer 1

it made up of a collection of differentiated cells that have a specialised function or functions. as a reuslt each tissue is adapted for a particular function within an organism

Question 2

what are the tissues in animals

Answer 2

nervous tissue
epithelial tisuues
muscle tissue
connective tissue

Question 3

what is the nervous tissue adapted for

Answer 3

supporting the transmission of electrical impulses

Question 4

what is the epithelial tissue adapted for

Answer 4

to cover body surfaces, internal and external

Question 5

what is the muscle tissue adapted for

Answer 5

to contract

Question 6

what is the connective tissue adapted for

Answer 6

to hold other tissues together or as a transport medium

Question 7

what are the features of epithelial tissues

Answer 7

• no blood vessels within the tissue. cells recieve nutrients by diffusion from tissue fluid in the undelrying connective tissue
• can have smooth surfaces or have projections
• have short cell cycles and divide 2,3 times a day to replace damaged cells

Question 8

what are two types of epithelial tissue

Answer 8

squamous and ciliated epithelial tissue

Question 9

how does the squamous epithelial tissue protect the skin and the alveoli

Answer 9

flattened cells are close to each other forming continous sheets

Question 10

how does the squamous epithelial tissue protect the arteries and veins

Answer 10

adjacent cells bound by lateral contacts such as tight junctions and desmosomes

Question 11

how does the squamous epithelial tissue allow for exchange in the capillary walls

Answer 11

thin walls give it a short diffusion distance

Question 12

how does the squamous epithelial tissue allow for absorption

Answer 12

they are ciliated with microvilli

Question 13

how does the ciliated epithelial tissue protect the trachea

Answer 13

• has hair like structures, sweeps mucus with trapped particles and lungs
• ciliated. goblet cells release mucus that trap dirt, dust and microbes

Question 14

what does connective tissue consist of

Answer 14

a non living extraceullalr matrix containing proteins (collagen and elastin) and polysaccharides which trap water. the matrix enables tissue to withstand forces

Question 15

give an example of connective tissue

Answer 15

cartilage

Question 16

what is cartilage

Answer 16

firm, flexible connective tissue composed of chondrocyte cells embedded in an extracellular matrix

Question 17

where is cartilage found

Answer 17

in the outer ear, nose and at the ends of and between bones

Question 18

what does cartilage contain

Answer 18

fibres of elastin and collagen

Question 19

what is the function of cartilage

Answer 19

prevents the ends of bones from rubbing together and causing damage

Question 20

what else contains connective tissue

Answer 20

blood, bone, tendons and ligaments, skin

Question 21

what does the connective tissue in blood do

Answer 21

transports nutrients and wastes throughout the body

Question 22

what is muscle tissue

Answer 22

elongated and contain special organelles called myofilaments made of the proteins actin and myosin. these allow the muscle tissue to contract

Question 23

what are three types of muscle tissue

Answer 23

skeletal, cardiac and smooth

Question 24

skeletal tissue

Answer 24

packaged by connective tissue sheets, joined to bones by tendons. when they contract, they cause the bone to move

Question 25

cardiac tissue

Answer 25

make up the walls of the heart allowing it to beat and pump blood

Question 26

smooth tissue

Answer 26

occurs in the walls of the intestine, blood vessels, uterus and urinary tracts propelling substances along these tracts

Question 27

what are tissues in plants

Answer 27

epidermal, vascular and meristem

Question 28

what is epidermal tissue adapted for

Answer 28

to cover plants surfaces

Question 29

what is vascular tissue adapted for

Answer 29

transport of water and nutrients

Question 30

what is meristem tissue adapted for

Answer 30

adapted for cell differentiation

Question 31

what is epidermal tissues

Answer 31

single layer of closely packed cells covering the surface of plants.

Question 32

why do epidermal tissues have a waxy cuticle

Answer 32

prevent water loss

Question 33

what is present in the lower epidermis

Answer 33

stomata allowing carbon dioxide in and out, and water vapour and oxygen in and out

Question 34

give features of epidermal tissue

Answer 34

- lack chloroplasts (apart from guard cells) - protective layer over leaves, stems and roots - root hairs increase the surface area for absorption

Question 35

what are the two types of vascular tissue

Answer 35

xylem and phloem tissue

Question 36

what is xylem tissue responsible for

Answer 36

transport of water and minerals throughout plants

Question 37

what are xylem tissues composed of

Answer 37

vessel elements (elongated dead cells). the walls of these cells are strengthened with a waterproof material called lignin providing structural support for the plant

Question 38

what is phloem tissue responsible for

Answer 38

transport of organic nutrients (sucrose) from leaves and stems to where it is needed.

Question 39

what are the organic nutrients made by

Answer 39

photosynthesis

Question 40

what is phloem tissue composed of

Answer 40

columns of sieve tubes cells separated by sieve plates

Question 41

what is meristematic tissue

Answer 41

- contains stem cells - all other plant tissues are dervied by cell differentiation from this tissue

Question 42

what are the features of meristematic tissue

Answer 42

thin walls with little cellulose no chloroplasts

Question 43

what is an organ

Answer 43

collection of tissues adapted to perform a particular function in an organism

Question 44

give two examples of organs

Answer 44

heart and leaf

Question 45

what is the heart adapted for

Answer 45

pumping blood around the body

Question 46

what is the heart made up of

Answer 46

made up of muscle and connective tissue

Question 47

what is the leaf adapted for

Answer 47

photosynthesis

Question 48

what is the leaf made up of

Answer 48

epidermal and vascular tissues

Question 49

what is an organ system

Answer 49

large multicellular organism have coordinated organ systems. each organ system is composed of a number of organs working together to carry out major functions in the body

Question 50

give examples of organ systems

Answer 50

digestive, cardiovascular, gaseous exchange system

Question 51

what is role of the digestive system

Answer 51

takes in food, breaks down the large insoluble molecules from small soluble ones. absorbs the nutrients into the blood, retains water needed by the body and removes any undigested material from the body

Question 52

what is the role of the cardiovascular system

Answer 52

moves blood around the body to provide an effective transport system for the substances it carries

Question 53

what is the role of the gaseous exchange system

Answer 53

brings air into the body so oxygen can be extracted for respiration and carbon dioxide can be expelled