cell biology Flashcards
(49 cards)
state the two eukaryotes cells?
Animal and plant cell
What does a eukaryotes cell contain?
nucleus
What is differentation?
when a cell specialises.
What is a stem cell?
an undifferentiated cell that can form the same type of cell or differentiate into a different type of cell.
Where are stem cells found in adults?
bone marrow
What can bone marrow differentiate into?
red blood cells/ white blood cells/ platelets
Describe a bone marrow transplant…
1) existing bone marrow destroyed by radiation
2) patient receives bone marrow transplant from donor
3) stem cells in bone marrow can form new bone marrow and differentiate to form new blood cells.
What are the dangers for donors?
1) viruses may be passed
2) must be compatiable otherwise wbc from the donor could attack patients body.
What is therapeutic cloning?
1) embryo produced with the same genes as patient
2)stem cells from the the embryo can be transplanted into patients body without being rejected by patients immune system
3)stem cells can differintiate to replace cells that have stopped working.
Who uses therapeutic cloning?
diabetes or paralysis
Why are some people against therapeutic cloning?
embryo is seen as a life
ethic and religious reasons.
What is the stem cell found in plants? (leaves and roots)
meristem
What are the uses of meristem?
clone a rare plant to stop it from getting extinct
clone crop plants for farmers
What is osmosis?
movement of WATER particles from a dilute solution to a concentrated solution, through a partially permeable membrane.
What happens to an animal cell in osmosis?
water moving in causes cell to expand, and could cause it to burst.
What happens to a plant cell in osmosis?
water moving in causes cell to expand, cell wall prevents cell from bursting.
becomes swollen (turgid)
What happens to an animal cell in a concentrated solution?
when the water moves out it will shrink
What happens to a plant cell in a concentrated solution?
water moves out and shrinks (flaccid)
Describe the method of osmosis…
1) peel the potato.
2) use a cork borer to produce three cylinders of potato with the same diameter.
3) use scalpel to trim the cylinders to the same length.
4) measure the length of potato using a ruler and mass using a balance.
5) place cylinders into three test tubes. 2 with sugar solution and one with distilled water.
6) leave over night to allow osmosis to take place.
7) gently role cylinders to get rid of any surface moisture.
8) measure length and mass again.
Describe the role of the sperm cell and how it is adapted for it’s function…
role: join with the egg cell (fusion of male DNA and
female DNA)
adaptation: long tail –> to swim to the egg /
packed full of mitochondria
for energy
contain enzymes which
allows them to digest
the outer layer of the egg
cell
Describe the role of the nerve cell and how it is adapted for it’s function…
role: send electrical impulses around the body
adaptation: axons cover large distances / myelin
insulates axon and speeds up the
transmission of electrical impulses /
synapses are junctions –> allow
impulses to pass from one nerve cell to
the other / dendrites creates a network
of nerve cells
Describe the role of the muscle cell and how it is adapted for it’s function…
role: contraction
adaptation: protein fibres decreasing the length of the cell / packed full mitochondria to provide energy
Describe the cell cycle and its process…
1) interphase –> DNA replicates to form two copies of each chromosome / grows and copies internal structures
2) mitosis –> one set of chromosome is pulled to opposite ends of the cell and nucleus divides
3) cytokonsis –> cytoplasm and cell membrane divide to form two identical daughter cells
What is the purpose of mitosis?
growth and repair / asexual reproduction
