Cells and cell transport Flashcards
Explain what happens to the level of the sucrose solution in the glass tube.
- The level of the sucrose solution will rise because of osmosis.
- The water molecules will move from an area of low concentration to an area of high concentration across a partially permeable membrane.
Explain why some plant cells contain many chloroplasts, some plant cells contain few chloroplasts and some plant cells contain no chloroplasts.
- Chloroplasts responsible for photosynthesis
- None in the root hair cells as they are not exposed to sunlight
- Many in the upper part of the leaf
Describe how this apparatus could be modified to measure the rate of osmosis at different temperatures.
- Use a Bunsen burner for hot water
- Have a ruler to measure the comparison
- Using a stopwatch, clock, etc to measure the time
What is meant by the term diffusion?
Diffusion is the movement of particles from an area of high concentration to an area of low concentration
Describe the effect of food dye concentration on diffusion.
- As concentration increases, the diameter increases
- The rate reduces at higher concentration
Explain the relationship between the food dye concentration and diffusion.
- Higher concentration, more particles in a given area
- Larger concentration gradient
State two variables that the student should control in this experiment to ensure that the results are valid.
- Volume of dye
- Same amount of agar
Explain what happens to a plant cell if it is put into a concentrated salt solution
- The water leaves the cell across a partially permeable membrane by osmosis
- The plant cell becomes flaccid, e.g. cell membrane peels away from the cell wall as there is a high solute concentration outside of the cell.
Name the organ that the student observes.
leaf
What is meant by the term organ?
A group of tissues working together to perform a particular job.
Name one structure which is present in both plant cells and fungal cells but not in animal cells
cell wall
