Chapter 1 - Cell Structure and Transport Flashcards
Give an advantage and disadvantage of using an electron microscope.
- Magnifying power up to about x2,000,000
- Quite expensive
Give an advantage and disadvantage of using a light microscope.
- Relatively cheap
- Magnifying power of only x2000
How do you calculate magnification?
Size of real object
How many nanometers are in a micrometer?
- 1000nm
How many metres are in a kilometer?
- 1000m
Name the five features of an animal cell.
- Nucleus
- Cytoplasm
- Cell membrane
- Mitochondria
- Ribosomes
Name 3 extra features found in a plant cell.
- Cell wall
- Chloroplasts
- Permanent vacuole
Explain the function of the cell wall.
- The cell wall is made of cellulose and strengthens and supports the cell.
State the function of the mitochondria.
- Where aerobic respiration takes place, releasing energy for the cell.
Give the function of the permanent vacuole.
- A space in the cytoplasm filled with cell sap. Keeps cells rigid to support the plant.
State 2 types of eukaryotic cells.
Animal and plant cells.
Give an example of a prokaryotic cell.
Bacteria.
Describe the structure of the bacterial cell.
- Cytoplasm and cell membrane surrounded by a cell wall.
- Cell wall doesn’t contain cellulose.
- A single DNA loop in the cytoplasm.
Give 3 examples of specialised animal cells.
- Nerve cell
- Sperm cell
- Muscle cell
State 3 adaptations of a sperm cell.
- Large nucleus with genetic information to pass on.
- Long tail to swim towards the egg.
- Mitochondria to produce energy to work.
Give 4 examples of specialised plant cells.
- Root hair cells
- Photosynthesis cells
- Xylem cells
- Phloem cells
Give 3 adaptations of the root hair cell.
- Increased surface area to allow water to move in.
- Large permanent vacuole to speed up movement of water by osmosis across the cell.
- Mitochondria to transfer energy needed for active transport of mineral ions.
Give 2 adaptations of the phloem cell.
- Cell walls between cells break down and form sieve plates, which allow water carrying dissolved food to move up and down.
- Mitochondria of companion cells transfer energy to move dissolved food up and down.
State the definition of diffusion.
Movement of particles from a high conc. to a low conc. down the conc. gradient.
Give 3 factors which affect the rate of diffusion.
- Difference in concentrations
- Temperature
- Surface area
Give 4 examples of dissolved substances moving in and out of cells by diffusion.
- Glucose
- Urea
- Co2
- O2
Define osmosis
- Movement of particles from a high conc. to a low conc. through a Partially Permeable Membrane.
Define dilute.
- Solution containing a high conc. of solvent and a low conc. of solute.
Define isotonic.
- When the conc. of solutes in the solution outside the cell is the same as the internal conc. of the cell.
Define hypertonic.
- When the conc. of solutes in the solution outside the cell is higher than the internal conc. of the cell.
Define hypotonic.
- When the conc. of solutes in the solution outside the cell is lower than the internal conc. of the cell.
What is turgor and why is it important?
- When no more water can physically enter the cell.
- Keeps the cell hard and rigid.
Define active transport.
- Movement of molecules from a lower conc. to a higher conc. against the conc. gradient.
Why is active transport important in root hair cells?
- Allows absorption of mineral ions required for healthy growth.
How does active transport function in a cell? [2]
Active transport uses energy released from respiration [1] to transport and provide energy required. [1]
