Movement Of Molecules In And Out Of Cells

Question 1

What are the cells, tissues and organs in plants and animals adapted to

What can affect this

Answer 1

Take up and get rid of dissolved substances

Different conditions effect the rate of transfer and sometime energy is needed for this to take place

Question 2

What do sports drinks contain

Answer 2

Water and ions to replace those lost through sweat

Sugar (usually glucose) to replace what’s lost in respiration

Question 3

What is a disadvantage to isotonic sports drink

Answer 3

They are expensive

Question 4

When would isotonic drinks be best

Answer 4

On a hot day as it restores more ions such as sodium ion and chloride ions that otherwise would be lost in sweat

Question 5

What 4 adaptations does a good exchange surface have

Answer 5

Large surface area
Thin thus, short diffusion pathway
Efficient blood supply to maintain a concentration gradient
Ventilation to maintain concentration gradient

Question 6

What do large animals have for gas exchange

Answer 6

Specialised exchange surfaces such as lungs/gills/small intestines as otherwise small SA to Vol
Small SA to Vol causes diffusion happens too slow

Question 7

What does an alveoli do and what characteristics does it contain to help it carry out this function

Answer 7

Gas exchange in lungs

Thin cells- diffusion distance short

Lobes- large surface area

Rich blood supply- supplies carbon dioxide and takes oxygen. Maintains steep concentration gradient

Ventilation supplies fresh co2 so steep concentration gradient