3- Exchange of materials

Question 0

What is osmosis

Answer 0

The diffusion of water from a dilute concentration to a concentrated solution through a partially permeable membrane

Question 1

What happens when red blood cells are in more dilute solution

Answer 1

Water goes into the red blood cell and the cell bursts due to the pressure

Question 2

What happens when red blood cells are in more concentrated solution

Answer 2

The red blood cells water travels out of the it and it collapses

Question 3

What happens when a plant cell is in more concentrated solution

Answer 3

The plant cells water travels out of it and it shrinks but does not collapse because of the cell wall

Question 4

What happens when a plant cell is in more dilute solution

Answer 4

Water goes into the plant cell and it swells up but does not burst because of the cell wall

Question 5

What is concentration

Answer 5

The measure of the number of particles of a solute in the solution

Question 6

What is distilled water

Answer 6

Pure water

Question 7

What is miscible liquids

Answer 7

Liquids that dissolve in each other

Question 8

What is the net movement

Answer 8

Overall movement

Question 9

What is a partially permeable membrane

Answer 9

A membrane which let’s some substances pass through, but not others

Question 10

What are pores

Answer 10

The holes in the partially permeable membrane

Question 11

What is a solution

Answer 11

A solid or gas dissolved in a liquid. Or two miscible liquids dissolved

Question 12

What is a solute

Answer 12

A dissolved substance in a solution

Question 13

What is a solvent

Answer 13

The liquid used for dissolving

Question 14

What is active transport?

Answer 14

The movement of particles against the concentration gradient (from low to high) through a partially permeable membrane. Energy released from respiration is required

Question 15

Examples of active transport?

Answer 15

Glucose in an animal cell (small intestine and kidney also)

Mineral ions into route hair cells

Question 16

Why is active transport necessary?

Answer 16

Cells may need to absorb substances which are in short supply (shorter supply than the cell has in it’s supply)

Question 17

What happens in your body while you exercise?

Answer 17

Glucose is used when your muscles respire to release energy. When the body becomes hot, you sweat more to cool down meaning you lose water and mineral ions

Question 18

What are the three basic ingredients in sports drinks?

Answer 18

Water, sugar and mineral ions

Question 19

What are sports drinks designed to do?

Answer 19

Balance the concentration of body fluids and concentration inside cells

If the drink concentration matches the body fluids, the solution is called isotonic

Question 20

What do scientists think of sports drinks?

Answer 20

Some think water is more effective, others think it is better because of the sugars and mineral ions. The general consensus is that is is only effective when exercising for a long period of time

Question 21

What is an exchange surface and give an example?

Answer 21

A surface on which materials are exchanged

Oxygen is absorbed by the lungs and carbon dioxide is removed from them (the gaseous exchange surface)

Question 22

What are qualities of an efficient exchange surface?

Answer 22

Large surface area, thin walls (short diffusion path), an efficient transport system

Question 23

What qualities does the lungs have that makes it so efficient?

Answer 23

Surface area increased by the alveoli (air sacks)

Ventilated to maintain a steep diffusion gradient

Question 24

Describe the process of gaseous exchange of the breathing system? (Detail)

Answer 24

Oxygen diffuses into the many capillaries surrounding the alveoli and carbon dioxide diffuses back out into the lungs to be breathes out

Question 25

Where are the lungs situated?

Answer 25

In the thorax, inside the rib age and above the diaphragm which separates the lungs from the abdomen

Question 26

What happens when we breath in?

Answer 26

The intercostal muscles (between ribs and diaphragm) contract The ribcage moves up and out The diaphragm flattens The thorax's volume increases and pressure decreases

Question 27

What happens when we breath out?

Answer 27

The intercostal muscles (between the ribs and diaphragm) relax The ribcage moves down The diaphragm becomes domed The thorax's volume decreases and pressure increases

Question 28

What is the diaphragm?

Answer 28

A strong sheet of muscle that separates the thorax and digestive organs, used to change the volume of the chest during ventilation of the lungs

Question 29

What is ventilation? (In terms of lungs)

Answer 29

The movement of air in and out of the lungs

Question 30

Give three reasons why someone cannot get enough oxygen into their blood stream?

Answer 30

If the alveoli is damaged (surface area decreased) Tubes leading to lungs narrowed Person is paralysed, muscles for ribcage will not work

Question 31

What are the three types of breathing aid? (Brief description)

Answer 31

~Iron lung - for people with polio or paralysed, a machine (metal cylinder) acts as your lungs and muscles ~Breathing aids - force measured amounts of air into the lungs to create a positive pressure (bag of air mask) ~Positive pressure aids - a smaller, more practical version of breathing aids

Question 32

What is the exchange surface for food molecules? Describe

Answer 32

The villi, lining of the inner surface of the small intestine. They are finger like projections which greatly incense the surface area, the walls are very thin with many capillaries close to them

Question 33

Describe the exchange of food molecules in the gut?

Answer 33

Food is digested in the gut into soluble molecules which are then absorbed into the blood in the small intestine. Diffusion or active transport takes place on the exchange surface that is the villi

Question 34

What is a stomata and what does it mainly do?

Answer 34

Oxygen and carbon dioxide diffuse (not very far because of the thinness) in and out of leaves through tiny holes called stomata. They size of them are controlled by guard cells (which surround them). The movement of the gasses depend on what process (photosynthesis or respiration) is taking place most quickly

Question 35

Why is oxygen needed in plants?

Answer 35

For respiration and is a waste product of photosynthesis

Question 36

Why is carbon dioxide needed in plants?

Answer 36

For photosynthesis and is a waste product of respiration

Question 37

What else does the stomata do, besides gas exchange?

Answer 37

Plants lose water vapour from leaf cells through the stomata due to evaporation in leaves

Question 38

What happens if plants lose water faster than the roots replace it?

Answer 38

The stomata can close to prevent willing

Question 39

What is the transpiration system?

Answer 39

The movement of water through the plant

Question 40

What inhances water evaporation in leaves?

Answer 40

Hot, dry, bright or windy conditions

Question 41

What can the guard cell do to prevent water loss in plants?

Answer 41

Can close or the leaves can wilt or collapse down to prevent water loss,

Question 42

What can a potometer measure?

Answer 42

The uptake of water by a plant with different conditions