Cells Flashcards
What parts are in an animal cell?
Cell membrane
Cytoplasm
Nuclear membrane
Nucleus
Mitochondria
What is the function of mitochondria
Where respiration takes place
What is the nuclear membrane
Surrounds the nucleus
What parts are only in the plant cell
Cellulose cell wall
Vacuole
Chloroplast
Chlorophyll
Function of cellulose cell wall?
A rigid structure outside the cell membrane that provides support.
Function of vacuole
Contains cell sap and when full pushes the cell membrane against the cell wall, providing support.
Cell membrane function
A selectively permeable boundary surrounding the cell which allows some substances to enter and leave the cell while preventing others.
Function of nucleus
Control centre of the cell. Contains the cells genetic information arranged in chromosomes.
What is diffusion
Diffusion is the random movement of a substance from a region of high concentration to region of low concentration.
What is the rate of diffusion affected by
Concentration gradient- a larger difference in the high and low concentrations increase diffusion rate
Temperature- higher temperature provides more kinetic energy
Surface area- a larger surface area through which diffusion can happen increases the diffusion rates.
What are stem cells
Stem cells are simple, unspecialised cells found in animal and plants that have the ability to divide to form cells of the same type. They can also differentiate into a variety of specialised cells.
Where can stem cells be harvested from
Embryonic umbilical cord or adult bone marrow
Where can stem cells be found in plants
Apical growing points or meristems at the end of shoots and roots.
Benefits of stem cells in medicine
Treating leukaemia. Chemotherapy and radiotherapy destroys new white blood cells in the patients body, stopping their bone marrow producing new blood cells. A bone marrow transplant contains stem cells from a matching donor allows healthy blood cells to be made in the patient.
Risks of stem cells in medicine
Risk of infection from the environment and donor as the chemo and radiotherapy leave the patient with no immune system
Stem cells may divide in an uncontrolled manner leading to the formation of tumours
Transfer of viruses or diseases from other animals
