1.2 Ultrastructure of cells Flashcards
What are prokaryotes?
Prokaryotes are cells without a nucleus
What domains are prokaryotes?
- Archaebacteria
- Eubacteria
Draw a prokaryote
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What are the important parts of a prokaryote?
- Cell wall
- Cell membrane
- Ribosomes
- Nucleoid region
Some have:
* Slimy capsule
* Plasmid
* Pili
* Flagella
What is the function of the slimy capsule?
Keeps bacteria from drying out
What is the function of the cell wall?
Provides structural support and protects the cell
What is the function of the cell membrane?
- Holds the cell together
- Seperates cell from others
- Semi-permeable
What is the function of ribosomes?
- Synthesis of proteins
- Made up of ribosomal RNA and protein
What is the function of the nucleoid region?
It’s 1 large circular DNA molecule
What is the function of the flagella?
Helps the bacteria swim
What is the function of the plasmid?
It’s a small ring of extra DNA
What is the function of pili?
Hair-like extensions that enable adherence to surfaces
How do prokaryotes replicate?
Through binary fission
What are the steps of binary fission?
- The single chromosome is replicated
- The copies move to opposite sides of the cell
- Division of the cytoplasm
- Each of the daughter cells contain one copy of the chromosome so they are identical
What are eukaryotes?
Cells that have a nucleus
Dram the structure of a typical animal cell
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What is the function of the nucleus?
- The control center of the cell
- Contains the DNA
What is the function of the golgi apparatus?
Packaging and modification of proteins
What is the function of the vacuole
Takes up a large space of a plant cell and affects wether the cell is turgid or not
What is the function of the rough endoplasmic reticulum?
Site of protein synthesis
What is the function of the smooth endoplasmic reticulum?
Synthesis of hormones and lipids
What is the function of the mitochondria?
- Where cell respiration takes place
- Contains oxidative enzymes that convert sugar to ATP
What is the function of the lysosome?
Contains enzymes that break down waste and phagocytosed material
What is the function of the centriole?
Function in cell division
Draw the structure of a typical plant cell
Compare to picture on bioninja
What is the function of the chloroplast?
- Contains chlorophyll
- Place where photosynthesis occurs
Compare DNA in prokaryotes and eukaryotes
Prokaryotes: Naked DNA
Eukaryotes: Protein bound DNA
Compare nucleus in prokaryotes and eukaryotes
Prokaryote: No nucleus
Eukaryote: Has nucleus
Compare organelles in prokaryotes and eukaryotes
Prokaryotes: No membrane-bound
Eukaryotes: Membrane-bound
Compare ribosomes in prokaryotes and eukaryotes
Prokaryotes: 70S
Eukaryotes: 80S
Compare reproduction in prokaryotes and eukaryotes
Prokaryotes: Binary fission
Eukaryotes: Mitosis and mieosis
Compare size in prokaryotes and eukaryotes
Prokaryotes: Smalles, about 1-5 µm
Eukaryotes: Larger, about 10-100 µm
Compare light microscopes and electron microscopes
Electron microscopes have much higher resolution than light microscopes
Why does electron microscopes have higher resolution than light microscopes?
Because beams of electrons have much shorter wavelength than beams of light
