B1.1 - Cell Biology Flashcards
parts of animal cell
mitochondria nucleus cytoplasm ribosome cell membrane
parts of plant cell
mitochondria nucleus cytoplasm ribosome cell membrane
cell wall
chloroplast
amyloplast - starch grain
vacuole
Nucleus
controls activities of cell, contains genetic material
Cell Membrane
barrier that controls what goes in and out of the cell - contains receptor molecules
Cytoplasm
jelly-like substance, cells chemical reactions occur here
Cell Wall
surrounds cell - made of tough fiber called cellulose. makes wall rigid and supports the cell
Chloroplast
made of green pigment - chlorophyll, only in green part of plant. Chlorophyll transfers sun energy to the plant as light - used in photosynthesis
Vacuole
full of cell sap, watery solution of sugars and salts. supports plant by keeping the cell rigid
mitochondria
contain enzymes for respiration - where respiration happens
- enzymes enable glucose + O2 to react together
Prokaryotes
- No nucleus genetic material floats in cytoplasm, often forms a ring - plasmid
- small (1-10μm)
- cell wall - peptidoglycan
- no mitochondria
- single-celled organism
- can have, flagella - movement, pili - attach to structures, slime capsules - protects cell
- examples - e.coli - food poising, streptococcus -sore throat
Eukaryotes
- nucleus - contains gen material
- larger (10-100-μm)
- some have cell wall - cellulose
- mitochondria
- often made of many cells
- organelles surrounded by membrane
- examples - plants, animals, fungi
Methylene blue
stains bacteria
Iodine
stains carbs
Crystal Violet
bacteria cell walls
Magnification =
Image size / actual size
I / A x M
Light microscope
- light rays - radiation used
- focusing with lenses
- magnification - X 1500
- resolution - 200nm
- living or dead biological matter
- small and portable
- easy to use
- quite cheap
- images produced in colour
Electron microscope
- Electron beam - radiation used
- focusing with magnets
- magnification - X 500,000
- resolution - 0.2nm
- Dead biological matter
- Very large and static ( not easily moved)
- not easy to use - skill & training required
- very expensive
- samples in a vacuum
- images produced in black and white
2 types of electron microscopes
- Transmission electron microscope ( TEM ) - sends electrons through a specimen, image produced is 2D
- Scanning electron microscope ( SEM ) - bounce electrons off surface of an object, images are 3D of the surface.
Specialised cell
has a specific role, each specialised cell has a different role. Group of specialised cells = tissue
Specialised cell examples
- red blood cells
- muscle cells
- ciliated epithelial cells
- fat cells
- sperm cells
- palisade cells
- root hair cells
Stem cells in animals
- Embryonic stem cells - found in embryos, have ability to differentiate into all cell types
- Adult stem cells - found in tissues such as brain, bone marrow, skin and liver, can differentiate into SOME not all types of cells
Stem cells in plants
- stem cells found in meristems which are in the roots and shoot tips and buds
- these stem cells have thin cell walls and small vacuoles compared to normal plant cells
Conditions stem cells have potential to treat
- spinal chord injury
- diabetes
- heart disease
- Parkinson’s disease
- Alzheimer’s disease
- however, is controversial as it involves use of human embryos and can be used in cloning
What sub-cellular structures do eukaryotic cells contain?
- mitochondria
- nucleus & nucleolus
- cytoplasm
- ribosomes
- cell membrane
- smooth and rough ER (endoplasmic reticulum)
what bacteria causes sore throats?
streptococcus
what sub-cellular structures does ALL bacteria contain?
- cell membrane
- cell wall
- cytoplasm
- genetic material
stem cell definition
- a cell that hasn’t yet become specialised
- undifferentiated
- able to turn into many different cell types
