Unit 1: Cells Flashcards
What is a cell?
A functional unit of cytoplasm with genetic material in a membrane
What are the 3 laws of cell theory?
Cell theory is based on evidence obtained through observation and experiments:
- Law 1 = All living things are made of one or more cells
- Law 2 = All cells come from pre-existing cells
- Law 3 = Cells are the smallest unit of life
What are the exceptions to cell theory?
- Many living things have non-cell parts (Law 1)
- Examples) teeth, outer part of bone, sea shells, liquid in eye, etc. - Where did all the first cells come from? (Law 2)
- There must have been a first cell
- L.U.C.A. (last universal common ancestor ) - Some cells are really big (Law 3)
- Giant algae grow really big - 10cm (Law 3) - Some cells have more than one nucleus (definition of cell)
- Muscle and fungal cells can have more than 1 nuclei (def. )
What are the functions of life?
Metabolism: All the chemical reactions that take place in an organism/cell
Response: An ability to react to the environment
Homeostasis: Controlling your “body” conditions
Example) Temperature, sugar control, water levels, etc.
Growth: An irreversible increase in size
Reproduction: Make more copies of one self
Excretion: Make waste
Nutrition: Consume nutrients
What are prokaryotes and how do they reproduce?
Prokaryotes are a domain of life including bacteria and archaeans
- Mostly unicellular organisms
- Example: Escherichia coli = E. coli
Prokaryotes reproduce by binary fission
- Bacteria grows and copies in DNA
- Bacteria splits in two, putting one molecules of DNA in each new cell
What does the structure of a prokaryote contain?
- Cytoplasm: Liquid filling the cell.
- Cell membrane: Controls what exits and enters the cell.
- Cell wall: Protects cell and gives the shape.
- Nucleoid: Region in the cytoplasm where the cell keeps the DNA.
- Mesosome: In-curling of the cell membrane to increase SA.
- 70S ribosomes: Makes proteins (does translation).
- Flagellum: Used for movement.
- Plasmid: Loop of DNA.
- Pilus: Allows bacteria to hold on to each other and allows bacteria to trade plasmid = conjunction
What does the structure of ALL eukaryotes contain?
- Cytoplasm: Liquid filling the cell
- Cell membrane: Controls what exits and enters the cell
- Nucleus: Double-membrane bound with linear DNA to control the cell
- Rough endoplasmic reticulum: Membrane bags with ribosomes, making proteins for export
- Vesicle: Membrane bag to move substances around the cell
- Golgi apparatus: Membrane bags that modify and label vesicles for export
- 80S ribosomes: Makes proteins for use inside the cell (does translation)
- Mitochondria: Make ATP / Do respiration
Which organelles only exist in eukaryotic animal cells?
- Centriole: Organizes the cytoskeleton (important during mitosis)
- Lysosomes: Digests eaten material and breaks down wastes
- Flagellum (sometimes): Used for movement
How are proteins exported in eukaryotes?
1) Proteins are made by bound ribosomes in the RER
2) Proteins from RER are put in vesicles
3) Vesicles move to and fuse with Golgi apparatus
4) Golgi modifies the proteins
5) Golgi puts proteins in another labelled vesicle
6) Vesicle moves to membrane and fuses with it
7) Releasing proteins outside of cell by exocytosis
Which organelles only exist in eukaryotic plant cells?
- Cell wall: Protects cell and gives the shape
- Vacuole: Large vesicle that stores water
- Chloroplasts: Organelles that do photosynthesis (converting light energy into chemical energy)
What are the similarities and differences between prokaryotes and eukaryotes?
PROKARYOTE vs. EUKARYOTE
- 70S Ribosomes vs. 80S Ribosomes
- Nucleoid vs. Nucleus
- Naked DNA vs. DNA + Protein
- 1 um vs. 100 um
- No mitochondria, RER vs. Has Mitochondria and RER
- No internal membranes vs. Organelles with membranes
- All have cell walls vs. Plants have cell walls but animals do not
-Both have cell membrane, ribosome, DNA and cytoplasm
What are the similarities and differences between animal cells and plants cells?
ANIMAL CELL vs. PLANT CELL
- No cell wall vs. Cell wall
- No Chloroplast vs. Chloroplast
- No Vacuole vs. Vacuole
- Lysosomes vs. No lysosome
- Centrioles vs. No centrioles
- Both have mitochondria, cell membrane, nucleus, 80S ribosomes, golgi apparatus, etc.
