Organisation - Transport in Cells Flashcards
What are three factors that affect the rate of photosynthesis?
- Light intensity
- CO2 concentration
- Temperature
What is an example of diffusion in plants?
CO2 diffuses into plant cells.
How do animals maintain a steep concentration gradient?
- Rich blood supply
- Network of capillaries
In a microscope, how do you adjust the magnification?
Adjust the objective lens
State the test and result for the protein.
Test: Biuret’s solution
Result: Blue to lilac
As a cell gets bigger, what happens to its surface area to volume ratio?
Decreases
What does an electron microscope use to observe cells?
A beam of electrons.
Which objective lens should always be used when starting to observe specimens using a microscope?
Lowest power
What does a light microscope use to observe cells?
Light
Why do exchange surfaces have thin membranes?
Short diffusion pathway
State the test and result for starch.
Test: Iodine
Result: Orange to blue/black
What are four adaption of alveoli for efficient gas exchange?
- Large surface area
- Thin membrane
- Rich blood supply
- Well ventilated
Why do the potato cylinders need to be dried before measuring their mass?
- Removes excess water
- Prevents the results from being corrupted
What are four adaptations of villi (in the small intestine) for efficient nutrient absorption?
- Large surface area
- Thin membrane
- Rich blood supply
- Many mitochondria
What is diffusion?
The movement of particles from an area of higher concentration to an area of lower concentration across a semi-permeable membrane.
