Limiting factors, Water transport, Osmosis, Organisms and the environment Flashcards Preview

Biology | GCSE - Edexcel - Additional > Limiting factors, Water transport, Osmosis, Organisms and the environment > Flashcards

Flashcards in Limiting factors, Water transport, Osmosis, Organisms and the environment Deck (15)
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What can limit the rate of photosynthesis?

- Light intensity.
- Carbon dioxide concentration.
- Temperature


Describe the structure of a root hair cell.

Long thin extensions with a large surface area.


What can the roots absorb?

Water, nitrates and other mineral ions that are dissolved in the water.


What is meant by osmosis?

Water moving through a semi-permeable membrane from a high to low concentration.


What is xylem and what is its role?

They are dead cell tubes that transport water. Because the tubes are dead cells they don't absorb, and stop others from absorbing, the transported water. The hollow tubes also give the plant structure.
(Remember XY and DIE rhyme, xylem are the dead hollow cells)


What is phloem tissue and what is its role?

It transports the sucrose made from glucose in leaves by photosynthesis to where it's needed in the plant.


What is meant by active transport? Give an example.

Absorbing particles against a concentration gradient. For example, The plant absorbing nitrate and mineral ions from the soil even though the concentration is higher in the plant than the soil water.


True or False:
The energy for active transport comes from respiration/



What happens when the stomata opens during transpiration?

Water diffuses through and onto the surface of the leaf and evaporates.


What happens to the roots when water is lost through transpiration?

They absorb more water and dissolved minerals.


How would you investigate osmosis in potatoes? (3 steps)

- Cut the potato and make sure that is the same mass and same kind of potato as the other samples.
- Put the potato in water for a set time.
- Measure the mass of the potato and this will tell you whether or not osmosis has taken place.


Draw and describe a pitfall trap.

- Used to collect small ground-living animals.
- A hole is dug in the ground and a container is placed there.
- Small stones support the lid off the ground so the animals call fall into the trap.
- Lid shelters trap from sun and rain.


How would you use a sweep net?

- Used to collect larger animals
- Sweep though grass, bushes, ponds, etc.
- Observe what you've captured in the net and then release.


How would you use a pooter?

- Hover the inlet tube over the animal if it is smaller.
- Sharply suck through the mouthpiece tube, you won't swallow the animal because of the mesh/net.
- Observe the animal and then release ASAP.


How would you use a quadrat effectively?

- Place randomly on the sample.
- Count the number or organisms in each quadrat.
- Repeat the measurement in several quadrats.
- Calculate the average measurement.