BIOLOGY REVISION- CELL BIOLOGY Flashcards
get all of the questions right and ONLY THEN you can move onto the exam questions deck for cell biology :)
What are the similarities & differences between eukaryotic cells(i.e animal & cells) and prokaryotic cells(i.e. bacterial cells) ?
Similarities:
-both contain DNA inside the cell
-Both have cytoplasm and cell membrane
-both have cell membrane surrounded by cell wall (plant cells and fungi)
Differences:
-Eukaryotic cells are bigger than prokaryotic cells
-eukaryotic cells have sub-cellular organells like ribosomes and mitochondria whereas prokaryotic cells don’t.
-eukaryotic cells divide by mitosis whereas prokaryotic cells divide by binary fission.
-in eukaryotic cells, the DNA is in nucleus however in prokaryotic cells the DNA is free in cytoplasm.
describe the function of every part in an animal & plant cell.
Clue: talk about the function of the nucleus, cytoplasm and 5 more!!
1) Nucleus- contains DNA
2) Ribosomes- where protein synthesis takes place
3) Cell membrane- controls the movement of substances in & out of the cell.
4) Cytoplasm- where all the chemical reactions in the cell take place
5) Mitochondria- where aerobic respiration in the cell takes place
6) chloroplasts- contains chlorophyll that traps sunlight for photosynthesis
7) permanenet vacoule-contains cell sap
What is a stem cell?
keyword: specialise :)
A stem cell is an undifferentiated cell that can be specialised to any cell to perform a speciliased function
what is a nerve cell and what are it’s adaptations?
the nerve cells send electrical impulses around the body.
functions:
-the nerve cell has a long axon with myelin insulating the axon to speed up the rate at whoch electric impulses are sent around the body.
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what is a muscle cell and what are it’s adaptations?
a muscle cell is contracted and relaxed for movement
functions:
-muscle cells have a lot of mitochondria to provide sufficient energy (via respiration) for muscle contraction.
-all muscle cells have layers of protein filaments in them. these layers can slide over each other causing muscle contraction.
what is the sperm cell and what are it’s adaptations?
there are 3 adaptations but one’s jst irrelavant….
the sperm cell fuses with an ovum (egg cell) and this is called fertilisation.
functions:
-The head of the sperm contains the genetic material for fertilisation. The acrosome in the head contains enzymes so that the sperm can penetrate an egg. The middle piece is packed with mitochondria to release energy needed to swim and fertilise the egg. The tail enables the sperm to swim.
What is a root hair cell and what is it’s adaptations?
a root hair cells absorbs water and minerals ions from the soil.
functions:
The root hair cell has a large surface area to provide contact with soil water. It has thin walls so as not to restrict the movement of water.
what are the adaptations of the xylem and phloem tissues in the plant?
xylem cell:
There are no top and bottom walls between xylem vessels, so there is a continuous column of water running through them. Their walls become thickened and woody. They therefore support the plant.
phloem cell:
Dissolved sugars and amino acids can be transported both up and down the stem. Companion cells, adjacent to the sieve tubes provide energy required to transport substances in the phloem.
what is a bone marrow transplant ans what are its disadvantages?
the stem cells in bone marrow differentiate to form cells found in our blood.
bone marrow transplant treat lukemia( cancer of the bone marrow).
diadvantages:
-bone marrow could not be compatible to the patient’s cells. Could attack the patient’s body.
-viruses could be passed from the donor to the patient.
What is therapeutic cloning and what are its advntages & disadvantages?
in therapeutic cloning, an embryo is produced with the same genes as the patient.
advantages:
-used to treat a range of medical conditions (i.e. diabetes or paralysis)
-stem cells can be into the patients’ body without being rejected.
-stem cells differetiate to various spealised cells to perform a certain function.
Disadvantages:
-religious and ethical beliefs.
-no consent given from donor
where is DNA found?
chromosomes carry genetic information in a molecule called DNA.
what is mitosis. describe in 3 stages in bullet points please and tyvm <33!!
Stage 1:
- DNA replicates to form copies of each chromosomes.
-cell growth
-sub-cellular organells begin to replicate in this stage(i.e. mitochondria & ribsomes)
Stage 2:
-mitosis takes place
-1 set of chromosome is pulled to each end end of the cell and the nucleus also divides.
stage 3:
-cytoplasm and the cell membrane divide to form 2 identical daughter cells.
what are the importance of mitosis?
1)Mitosis is essential for growth and development in multicellular organisms
2)Mitosis happens during assexual reproduction
3)Mitosis happens so cells can repair
What are chromosomes?
follow-up question hehe:
what are genes?
DNA exists in a cell’s nucleus withing structures called chromosomes.
each section of a chromosome that contain the code of reproduction of a particular protein is called a gene.
