Exchange of materials with the environment

Question 1

unicellular organisms exchange ___ and __ with their envrionment

Answer 1

carbon dioxide and oxygen

Question 2

multicellular organisms exchange __ with their environment

Answer 2

materials

Question 3

m___ are take in by the animal including ___, water and various substance contained in food e.g. carbohydrates, ___,__, ___ and ____

Answer 3

materials are taken in by the animal including oxygen, water and various substance contained in food e.g. carbohydrates, proteins, lipids, vitamins and minerals

Question 4

what are some materials released by animals?

Answer 4

excess water, slats and toxic substances produced by biochemical reactions e.g. carbon dioxide and nitrogen containing waste like uric or urea acid.

Question 5

unicellular organisms exchange materials ___ with the ____

Answer 5

unicellular organisms exchange materials directly with the environment

Question 6

why are most cells unable to exchange materials directly with the environment?

Answer 6

because they do not have direct contact with the environment

Question 7

to cope with this multicellular organisms have __ composed of cells in certain __ specialised for exchange called an _______

Answer 7

to cope with this multicellular organisms have structures composed of cells in certain organs specialised for exchange called an exchange surface

Question 8

exchange surface areas must be what?

Answer 8

1. thin to reduce the distance the materials need to move during exchange
2. moist which assist the transport of materials across the exchange surface
3. large total surface area which provides more surface for exchange to take place

Question 9

the exchange of __ is facilitated by exchange surfaces being close to a supply of ___ transporting the material from the ____ to the __ in the body

Answer 9

the exchange of materials is facilitated by the exchange surface being close to a supply of blood transporting the materials from the exchange surface to the cells in the body

Question 10

what is diffusion?

Answer 10

the movement of substance across an exchange surface

Question 11

substances aid to be exchanged by this are said to ____

Answer 11

diffuse

Question 12

movement of substance from a region of _____ to ___ until the two regions have an ___ of substance

Answer 12

movement of substance from a region of high concentration to low concnetration until the two regions have an ewual concentration of the substance

Question 13

a way to describe diffusion is?

Answer 13

the movement of substance down its concentration gradient until equilibrium has been reached

Question 14

is diffusion passive?

Answer 14

yes

Question 15

why does oxygen diffuse into the cell?

Answer 15

oxygen diffuses into the cell as it is needed for the process called aerobic respiration

Question 16

aerobic respiration enables the cell to?

Answer 16

make energy available for them to function

Question 17

what is a waste product produced by aerobic respiration ?

Answer 17

carbon dioxide

Question 18

what are apart of the external environemnt?

Answer 18

surroundings

Question 19

what are apart of the internal environments?

Answer 19

blood supply and body cells of multicellular organism

Question 20

what is the function of the exchange surface?

Answer 20

to permit exchange of materials between external and internal environments of organisms

Question 21

where does the exchange of gases in animals happen?

Answer 21

in the respiratory system in the alveoli

Question 22

the ___ of the respiratory system facilitates the __ of gases by moving the external environment e.g. air to or from the ___

Answer 22

the structure of the respiratory system facilitates the exchange of gases by moving the external environment e.g. air to or from the alveoli

Question 23

gas exchange by diffusion takes place because air in the ___ is in close contact with the __ environment, the blood transported to or from the __

Answer 23

gas exchange by diffusion takes place because the air in the alveoli is in close contact with the internal environment, blood transported to or from the lungs

Question 24

movement in and out of the __ is called __

Answer 24

alveoli, ventilation

Question 25

air that moves into the lungs and alveoli is called ___

Answer 25

inhalation

Question 26

air is inhaled when the pressure inside the lung is ___ than the air outside the body.

Answer 26

lower

Question 27

this is achieved by the contraction of the ___ and the ____muscles that move the diaphragm ___ and the ribs outwards

Answer 27

diaphragm, intercostal, downwards

Question 28

air moving out of the lungs is called ___

Answer 28

exhalation

Question 29

air is exhaled when the lung air pressure is __ than the air pressure outside of the body

Answer 29

greater

Question 30

this occurs when the diaphragm and the intercostal muscles __ causing the diaphragm to move upwards and the ribs downwards and inwards

Answer 30

relax

Question 31

each lung has a huge number of __ which creates a very large surface for __ to occur

Answer 31

alveoli, exchange

Question 32

the outside of the alveoli is covered with a lot of __ that transport blood to and from them

Answer 32

capillaries

Question 33

why is the distance for diffusion very small

Answer 33

because the alveoli surface are consist of a single layer of epithelial tissue which makes it very thing

Question 34

how is the exchange off gases across the alveoli assited?

Answer 34

by the presence of a film of moisture that covers the inside surface of them

Question 35

Cells need to exchange material in order to what?

Answer 35

survive

Question 36

Cells take in what?

Answer 36

• oxygen
• glucose
• amino acids
• water
• mineral ion

Question 37

cells remove what?

Answer 37

• carbon dioxide
• urea
• lactic acid

Question 38

Exchange surfaces are made up of what?

Answer 38

a single layer of epithelial cells

Question 39

cells need to be what when passively exchanging materials?

Answer 39

efficient

Question 40

efficient exchange occurs when what?

Answer 40

cells are THIN - for rapid exchange
there are MOIST surfaces - to help exchange
there is a LARGE SURFACE AREA - to maximise exchange
exchange surfaces are CLOSE TOGETHER - for rapid exchange

Question 41

Thin = what?

Answer 41

less tissue for the moving molecule to pass through

Question 42

moist = what?

Answer 42

molecules diffuse more efficiently through a liquid medium

Question 43

large surface are = what?

Answer 43

a lot of molecules can pass through - aiding in efficiency of exchange

Question 44

exchange surface are close together = what?

Answer 44

molecules have a smaller distance to move

Question 45

Diffusion is a what?

Answer 45

a passive transport process - it does not require energy to occur

Question 46

diffusion describes what?

Answer 46

the movement of molecules from regions of high concentration to low concentrations along a concentration gradient

Question 47

Where are the [air of lungs located?

Answer 47

within the thorax

Question 48

the lungs are connected to the outside air by way of a system of tubular passageways - describe them

Answer 48

• trachea
• bronchi
• bronchioles

Question 49

the diaphragm is a dome-shaped sheet of what?

Answer 49

skeletal muscle

Question 50

The ___ divides into two ___ each of which leads to one lung

Answer 50

trachea, bronchi

Question 51

Each __ divides many times into ____ _____

Answer 51

bronchus, respiratory bronchioles

Question 52

The __ are the site of __ and ___ in the lungs

Answer 52

alveoli, oxygen and carbon dioxide exchange

Question 53

the alveoli tend to what?

Answer 53

recoil inward (deflate) after each breath

Question 54

The alveoli are the site of gas exchange in the lungs:

Answer 54

• the air sac increase the surface area
• they have thin, moist membranes that are close to blood vessels
• oxygen diffuses into the blood, and into the haemoglobin of red blood cells
• carbon dioxide diffuses from blood into air sacs