What is the chemical equation for photosynthesis?
6CO2 + 6H2O + energy –> C6H12O6 + 6O2
What is in the vascular bundle?
Xylem and phloem
What is involved in transport of water in a plant?
Root pressure
Adhesion
Cohesion (Water is a polar molecule so it sticks to itself)
Transpiration (water goes out through stomata)
Say something about capillaries…
They are one cell thick
In a leaf cross section, there are… (top –> bottom)
Upper epidermis (and waxy cuticle) Palisade Spongy Mesophyll Vascular bundle Lower epidermis (and stomata and guard cells)
How do guard cells work?
Potassium comes in, water flows in through osmosis, the cells swell up and open. To close the potassium leaves and so then the water goes out through osmosis.
What is the function of the waxy cuticle?
Keeps out water from passing through the upper epidermal cells.
Efficient cells should have
High surface area : low volume ratio
Why is the SA:V ratio in a cell important?
High SA: can absorb lots of things (ie. sunlight) and creates more space for things to diffuse across
Low V: Less distance to cover for transporting nutrients to all parts of the cell. Also easier to get info to the nucleus.
What is gravitropism?
Growing in the direction gravity is pushing the plant.
What is phototropism?
Growing towards the light.
Where does most of photosynthesis happen?
Palisade cells
What is the function of spongy mesophyll?
Provides space for gas exchange
What does the xylem do?
Transports water
What does the phloem do?
Transports glucose and nutrients
What makes up the membrane?
Phosphoheads and fatty acid tails.
What in the membrane doesn’t like water?
The fatty acid tails are hydrophobic.
What do root hairs do?
Increase the surface area of roots for the absorption of water.
What is transpiration?
Process of water vapor leaving the leaf through stomata.
What is cohesion?
Water molecules attach to each-other because they are polar.
What is adhesion?
Water is attracted to and attaches itself to other substances
What is root pressure?
Upward force exerted on water in the xylem.
What are tropisms?
Control systems. Ie. phototropism and gravitropism
