Biology unit 1,2 & 3

Photosynthesis uses sunlight energy to transform it into chemical energy in bonds of glucose. 

Glucose

• Stored as starch
• Used in respiration for energy
• With nitrate it produces protein for growth
• Turned into sucrose for transporting
• Turned into cellulose for cell walls 

A limiting factor: factors that limit the rate of photosynthesis. 

So the limiting factors are 

1) light intensity

2) Carbon dioxide concentration

3) Temperature

Glucose provides: 

• respiration
  
• growth
• movement 

• Large surface area - absorb more light
• Thin - Short distance for Carbon dioxide to diffuse into leaf across cells.
• Chlorophyll- Absorb sunlight energy into chemicals.
• Veins- Support leaf,  transport water.
• Stomata_  Allow carbon dioxide to diffuse into leaf
• Cuticle of wax- Protect leaf, without reducing sun light
• Palisade cells- Contain chloroplasts to absorb light. 

CELLS- something that all living things are made up of.

A bundle of cells called tissues.

TISSUES- Bundle of unspecialized cells, they for together to perform a similar function. 

Epidermal cells cover plants.

Mesophyll tissue carry out photosynthesis in leaf

Xylem and phloem transport around leaf

• Light- limits the amount of photosynthesis
• Water availability- a necessary life source
• Availability food- another necessary life source
• Temperature- in the arctic, plants are small
• Nutrients- another essential life source

• Scientists carry out investigations, under the same conditions, this increases reproducibility.
• Although the outdoors, you can't contol certain variables, such as weather.
• In a lab, you are able to control a lot more. 

Hydroponic growing- growing a plant without soil.

This means mineral levels are controlled!