Cells Flashcards
What is the function of the nucleus?
Contains genetic material (DNA) which controls the activities of the cell.
What is the function of the vacuole?
Contains cell sap for support.
What is different about a bacterial cell compared to a plant cell?
Has a non cellulose cell wall.
No nucleus (large DNA molecule)
Contains plasmids
Name the two lens on a microscope.
The eye piece lens
The objective lens
What is meant by the term resolution?
The ability to discriminate between two separate points (see fine detail)
On making a temporary slide with a coverslip, why do we stain the epidermis of onion with iodine?
The onions epidermis is transparent so iodine is used to stain it so it is easier to see
On making a temporary slide with a coverslip, what is the purpose of the coverslip?
Why does it have to be lowered slowly onto the slide?
The purpose of the coverslip is to prevent the specimen from drying out and protect the lens.
It has to be lowered down slowly to prevent air bubbles from forming.
Name three differences between an electron microscope and a light microscope:
The electron microscope has more resolution and the light microscope has less resolution. The electron has more magnification and the light has less magnification. The electron is cumbersome and the light is easy to carry.
What is the function of a root hair cell?
To absorb water and minerals
What is the function of the ciliates epithelium cell?
To sweep mucus away from the respiratory system.
Name the levels of organisation in order:
Cell
Tissue
Organ
Organ system
Organism
What are stem cells?
Simple unspecialised cells that can divide and form cells of the same type. They can differentiate into a variety of cell types.
Name three sources of stem cells:
Unused embryos
Harvested from the umbilical chord
Taken from adult bone marrow
Where are stem cells found in a plant?
The meristem
Uses of stem cells in medicine:
Making new brain cells for people with Parkinson’s disease, rebuilding bones and cartilage, repairing damaged immune systems, treating leukaemia (a cancer where someone produces too many abnormal white blood cells)
