3.5- CELL SPECIALISATION AND ORGANISATION

Question 1

What are cells specialised to do in multicellular organisms?

Answer 1

to perform specific functions

Question 2

What are similar cells grouped into?

Answer 2

tissues

Question 3

What are tissues grouped into?

Answer 3

organs

Question 4

What are organs grouped into?

Answer 4

organ systems

Question 5

Why is the grouping of cells -> tissues -> organs -> organ systems done for?

Answer 5

increased efficiency

Question 6

Can any one cell provide the best conditions for all functions?

Answer 6

no

Question 7

As cells cannot provide the best conditions for all functions, what do the cells do in multicellular organisms?

Answer 7

cells specialised in different ways to form particular role

Question 8

What has specialised cells evolved?

Answer 8

more or fewer of certain organelles + structures to suit role it carries out

Question 9

What is the first group of cells in an embryo initially?

Answer 9

initially identical

Question 10

What happens to the cell as the embryo matures?

Answer 10

each cell takes on its own individual characteristics that suit it to the function it will perform when it’s mature

Question 11

How are all cells in an organism, such as a human produced?

Answer 11

by mitotic divisions from fertilised egg

Question 12

As all the cells in an organism are produced by mitotic divisions from a fertilised egg, what follows?

Answer 12

they all contain exactly the same genes

Question 13

What do cells have for them to develop into any one of the many different cells in an organism?

Answer 13

every cell contains genes

Question 14

How are the genes used in a cell for them to be specialised?

Answer 14

only some of the genes switched on (expressed) in a cell, at any one time. rest of the genes switched off

Question 15

What will muscle/sperm cell have a lot of?

Answer 15

mitochondria

Question 16

What do white blood cells have many of?

Answer 16

lysosomes

Question 17

What is done to cells for working efficiency?

Answer 17

cells are normally aggregated together

Question 18

What is a tissue?

Answer 18

collection of similar cells that perform a specific function

Question 19

Examples of tissues? (2)

Answer 19

epithelial tissues

xylem

Question 20

Where are epithelial tissues found?

Answer 20

in animals

Question 21

What do epithelial tissues consist of?

Answer 21

sheets of cells

Question 22

What do epithelial tissues line?

Answer 22

line surfaces of organs

Question 23

What function do epithelial tissues often have?

Answer 23

protective or secretory function

Question 24

Types of epithelial tissues? (2)

Answer 24

thin, flat cells

ciliated epithelium

Question 25

What do thin, flat cells of epithelial tissues line and what happens here?

Answer 25

line organs where diffusion takes place

Question 26

Example of where thin, flat cells of epithelial tissue line?

Answer 26

alveoli of lungs

Question 27

Example of where ciliated epithelium of epithelial tissue line?

Answer 27

a duct i.e. trachea

Question 28

What is the cilia of the ciliated epithelium of epithelial tissue used to do?

Answer 28

move mucus over epithelial surface

Question 29

Where does the xylem occur?

Answer 29

in plants

Question 30

What is the xylem used for? (2)

Answer 30

to transport water + mineral ions throughout plant give mechanical support

Question 31

What are tissues aggregated into?

Answer 31

organs

Question 32

What is an organ?

Answer 32

combination of tissues coordinated to perform variety of functions although they have one predominant major function

Question 33

In animals, what is the stomach organ involved in?

Answer 33

digestion of certain types of food

Question 34

What tissues is the stomach made up of? (3)

Answer 34

muscle epithelium connective tissue

Question 35

What do the muscle tissues do in the stomach?

Answer 35

churn + mix stomach contents

Question 36

What do the epithelium tissue do in the stomach?

Answer 36

protect stomach wall + produce secretions

Question 37

What do the connective tissue do in the stomach?

Answer 37

hold together the other tissues

Question 38

What tissues is the leaf made up of? (5)

Answer 38

``` palisade mesophyll spongy mesophyll epidermis phloem xylem ```

Question 39

What is the palisade mesophyll of the leaf made up of?

Answer 39

leaf palisade cells

Question 40

What do the palisade mesophyll do in the leaf?

Answer 40

carry out photosynthesis

Question 41

What is the spongy mesophyll in the leaf adapted for?

Answer 41

gaseous diffusion

Question 42

What do the epidermis do in the leaf?

Answer 42

protect leaf + allow gaseous diffusion

Question 43

What do the phloem do in the leaf?

Answer 43

transport organic materials away from leaf

Question 44

What do the xylem do in the leaf?

Answer 44

transport water + ions into leaf

Question 45

Are capillaries organs?

Answer 45

no

Question 46

Are veins and arteries organs?

Answer 46

yes

Question 47

What is the function of arteries, veins and capillaries?

Answer 47

transport of blood

Question 48

What tissue is the capillary made up of?

Answer 48

epithelium

Question 49

What tissues are the veins and arteries made up of?

Answer 49

epithelial, muscle + other tissues

Question 50

What is the single unit that organs work together in called?

Answer 50

organ system

Question 51

Why are organs grouped together?

Answer 51

to perform particular functions more efficiently

Question 52

Examples of organ systems in humans? (3)

Answer 52

digestive system respiratory system circulatory system

Question 53

What does the digestive system do?

Answer 53

digest + process food

Question 54

What organs are in the digestive system? (7)

Answer 54

``` salivary glands oesophagus stomach duodenum ileum pancreas liver ```

Question 55

What does the respiratory system do?

Answer 55

used for breathing + gas exchange

Question 56

What organs are in the respiratory system? (3)

Answer 56

trachea bronchi lumps

Question 57

What does the circulatory system do?

Answer 57

pumps + circulates blood

Question 58

What organs are in the circulatory system? (3)

Answer 58

heart arteries veins