cell biology
Cards (34)
- the nucleus is the control centre of the cell, it contains DNA which controls all activities within the cell
- mitosis is when one cell divides into two identical daughter cells
- mitochondria are found in eukaryotic cells only, they produce energy from glucose through respiration
- chloroplasts contain chlorophyll and are found in plant cells, they absorb light to make food during photosynthesis
- meiosis is where one parent cell divides to produce four genetically different gametes (eggs or sperm)
- cell membrane separates inside of cell from outside, allows substances to pass across by diffusion or active transport
- gametes fuse together at fertilisation to form a zygote
- a zygote undergoes mitosis to create an embryo
- cytoplasm is jelly-like substance containing enzymes which carry out chemical reactions within the cell
- eukaryotic cells
- animals
- plants
- fungi
- prokaryotic cells
- bacteria
- prokaryotic cell structure
- cell membrane
- cell wall
- cytoplasm
- plasmids
- circular loop of DNA
- flagellum
- animal cell structure
- cell membrane
- nucleus
- ribosomes
- mitochondria
- cytoplasm
- plant cell structure
- nucleus
- cell membrane
- cell wall
- ribosome
- mitochondria
- chloroplast
- vacuole
- cytoplasm
- chloroplast
- Organelles that contains the green pigment, chlorophyll, which absorbs light energy for photosynthesis. Contains the enzymes needed for photosynthesis.
- permanent vacuole
- filled with sap to keep the cell turgid
- Comparing eukaryotic and prokaryotic
- prokaryotic cells are far smaller
- prokaryotic cells do not contain mitochondria or chloroplasts
- DNA is found in a circular loop
- sperm cell specialisation
- head of the sperm contains genetic material
- the acrosome in the head contains enzymes to help penetrate the egg
- the middle is packed with mitochondria to release energy to swim
- tail enables the cell to swim
- Nerve cell specialisation
- has extensions and branches to send signals to other nerve cells, muscles and glands
- covered in a fatty sheath to insulate the cell and speed up electrical signals
- Muscle cell specialisation
- contain lots of mitochondria to provide enough energy to contract
- layers of protein that slide over eachother and contract
- Root hair cell specialisation
- large surface area
- thin walls that make it easier for water to move in and out
- Xylem cell specialisation
- no top and bottom walls to allow water through
- thick walls to support the plant
- phloem cells are specialised plant cells
- Stem cells are cells that have not undergone differentiation. A cell which has not yet become specialised is called undifferentiated.
- Adult stem cells are found in
- brain
- muscle
- bone marrow
- heart
- liver
- bone marrow cells can differentiate into blood cells and cells of the immune system but not other cell types.
- The process of creating an embryo is known as fertilization. The sperm enters the egg and fuses with its nucleus. This creates a zygote - a single-celled organism containing genetic material from both parents.
- Embryonic stem cells can be used to treat diseases such as diabetes, Parkinson's disease and heart failure by replacing damaged tissue with healthy tissue made from these cells.
- the zygote divides by mitosis, producing two daughter cells
- stem cells can be used to treat
- type 1 diabetes
- multiple sclerosis
- spinal cord injury
- brain injury
- .Bone marrow cells will differentiate into different types of blood cell. Bone marrow transplants are carried out:
- in cases of blood cell cancer such as leukaemia and lymphoma
- when blood cells have been destroyed by cancer treatment
- embryonic stem cell
- found in embryo
- can divide into almost any cell
- unethical to collect as best found in 5 day old embryos
- adult stem cell
- found in specific locations in adults
- can only differentiate into limited number of cell types
- issues with stem cell transplants
- may not work
- embryonic stem cells not always seen as ethical to use
- can be difficult to find a stem cell donor