Cells Flashcards
Function of a nucleus.
To control the cell’s activities.
Function of cytoplasm.
Where many chemical reactions take place.
Function of a ribosome.
Where protein synthesis takes place.
Function of a mitochondrion.
Where energy is released during aerobic respiration.
Function of a cell membrane.
To control the movement of substances into and out of the cell.
What is a cell wall?
Made of cellulose for support.
Function of chloroplasts.
Contain chloroplasts for photosynthesis, the chloroplasts absorb light energy to make food.
Function of a permanent vacuole.
Well cell sap is stored.
What are algae?
They are simple aquatic organisms which have many features similar to plants.
Where is the genetic material found in a bacteria cell and why?
The genetic material is in the cytoplasm because bacteria cells do not have a nucleus.
What is formed when bacteria multiply? What is different about these compared to single bacteria cells?
When they multiply they form colonies, which can be seen with the naked eye.
How are mesophyll cells specialised?
They contain many chloroplasts for photosynthesis.
How are gland cells which produce enzymes specialised?
They contain many ribosomes to make a lot of protein.
For what function are neurones specialised?
They are specialised to carry electrical impulses to the CNS.
Why are root hair cells important?
They increase the surface are of the root so that it can absorb water and mineral ions efficiently.
What is diffusion?
Diffusion is the net movement of particles from an are of high to low concentration.
What is the concentration gradient?
How does the steepness of the concentration gradient affect diffusion?
The difference in concentration between two areas.
The steeper the concentration gradient the faster the rate of diffusion.
Give three examples of diffusion.
1) The diffusion of oxygen into the cells of the body from the bloodstream as the cells are respiring (and using up oxygen).
2) The diffusion of carbon dioxide into actively photosynthesising plant cells.
3) The diffusion of simple sugars and amino acids from the gut through cell membranes.
On what does the net movement into or out of cells depend?
The concentration of particles on each side of the cell.
What happens to cells during the development of a multi-cellular organism?
They differentiate.
What is a tissue?
A tissue is a group of cells with similar structure and function.
Name three animal tissues and describe their function.
1) Muscular tissue, contracts to bring about movement.
2) Epithelial tissue, covers the inside and outside of the body.
3) Glandular tissue, produces and secretes hormones and enzymes.
Name three plant tissues and describe their function.
1) Epidermal tissue, covers the plant
2) Mesophyll tissue, which can photosynthesise
3) Xylem and phloem, which transport substances around the plant.
What three tissues make up the stomach and what are their role?
1) Muscular tissue, churns up the stomach contents - mechanical digestion.
2) Glandular tissue - to release digestive juices.
3) Epithelial tissue to cover the outside and inside of the stomach.
What three tissues do the stem, leaf and root organs contain?
1) Epidermal tissue
2) Mesophyll
3) Xylem and phloem
What are organ systems?
Groups of organs working together to perform particular functions.
What must be done before food can be absorbed into the bloodstream?
Which organ system is responsible for this process?
The food eaten by an individual must be changed from insoluble molecules into soluble molecules, then the soluble molecules can be absorbed into the bloodstream.
The digestive system.
The digestive system is a muscular tube which includes what five main things?
1) Glands such as the pancreas and the salivary glands which produce the digestive juices,
2) The stomach and small intestine where digestion occurs.
3) The liver which produces bile.
4) The small intestine where the absorption of soluble food occurs.
5) The large intestine where food is absorbed from undigested food, producing faeces.