Photosynthesis

Question 1

word and symbol equation of photosynthesis(it is endothermic)

Answer 1

Light energy
Carbon dioxide +water—>glucose + oxygen
6CO2 + 6H20–>C6H1206+602

Question 2

Where does photosynthesis take place

Answer 2

The chloroplasts

Chlorophyll absorb/trap light(energy transferred to chloroplasts

Question 3

5 ways plants use glucose

Answer 3

• Respiration-transfers energy from glucose,plant uses glucose for other stuf
• making cellulose-glucose converted to cellulose for cell wall
• making amino acids-glucose+nitrate ions=amino acids =proteins for growth
• stored as fats and oils-turned into lipids for storing in seeds
• Stored as starch-stored in roots,stems and leaves(for winter)starch is insoluble(good because glucose draws in water and swells)

Question 4

4 Limiting factors that affect the rate of photosynthesis

Answer 4

• light intensity(night)
• CO2 concentration(if it’s warm and sunny then)
• temperature (winter)
• chlorophyll concentration (disease,environmental stress like lack of nutrients

Question 5

Not enough light slows photosynthesis rate

Answer 5

• light provides energy for photosynthesis
• more light =more photosynthesis up to a certain point
• due to a limiting factor eg temperature
• we can change light intensity by moving a lamp closer or further

Question 6

Too little carbon dioxide also slows photosynthesis rate down

Answer 6

• co2 is a raw material needed for photosynthesis
• more co2=more photosynthesis up to a point
• after graph flattens showing there is a different limiting factor

Question 7

The temperature has to be just right

Answer 7

• if temperature is the limiting factor it’s too low
• enzymes work slower in lower temperatures
• At 45 C enzymes denature

Question 8

Inverse square law equation

Answer 8

Light intensity is proportional to 1/distance (d)2

So if you double distance light intensity is x4 as small

Question 9

Artificially creating ideal conditions for farming

Answer 9

• Greenhouse-traps suns heat so temperature isn’t a limiting factor
• shades+ventilation if too hot
• use heater in winter
• artificial light at night
• paraffin heater-increases carbon dioxide (by product)
• enclosed means no pests
• add fertilizer (more minerals-chlorophyll)

Question 10

What is respiration

Answer 10

The process of transferring energy from the break down of glucose
Food—>cells
Exothermic

Question 11

3 ways of Using energy from respiration

Answer 11

Build bigger molecules from small ones eg proteins from amino acids

In animals Allow muscles to contract (move)

In mammals+birds-keep body temp steady in colder surroundings

Question 12

What is metabolism

Answer 12

Sum of chemical reactions which are controlled by enzymes (biological catalysts)

Question 13

In some reactions larger molecules are made from smaller ones

Answer 13

Lots of glucose molecules join to make starch(storage in plants),glucagon(a storage molecule in animal cells) and cellulose ( a component of plant cell walls)
Lipids made from glycerol and three fatty acids
Proteins made from glucose nitrate ions and amino acids

Question 14

In other reactions larger molecules are broken down into smaller ones

Answer 14

Glucose broken down in respiration (transfers energy to power all reactions

Excess proteins broken into urea.which is excreted in urine

Question 15

Aerobic respiration is

Answer 15

Most efficient way to transfer energy from glucose

Happens in mitochondria

Question 16

Aerobic word and symbol equations

Answer 16

Glucose+oxygen—>carbon dioxide+water

c6h12o6+6o2–>6CO2+6h2o

Question 17

Anaerobic reputation is

Answer 17

When your body can’t supply oxygen to your muscles

The incomplete breakdown of glucose making lactic acid(allows you to use muscles for longer)

Question 18

Oxygen debt

Answer 18

Amount of extra oxygen needed to break down lactic acid and remove it from cells so we breath harder to get more oxygen in the blood which is transported to the muscles
Or
Lactic acid is transported to the liver by the muscles and converted back to glucose

Question 19

Anaerobic respiration in yeast

Fermentation

Answer 19

Yeast +Glucose->ethanol + carbon dioxide
Used in brewery
Used to make bread rise

Question 20

Example of metabolic reactions

Answer 20

Glucose—>starch
—>cellulose
—>glycogen

Fatty acids+glycerol—>lipids