Cell Structure and Function Flashcards
What is the Cell Theory?
Cells are the unit of life,
All living things are made up of cells.
All new cells come from pre-existing cells (Virchow)
Who proposed the Cell Theory?
Schleiden and Schwann
Classify cells on the basis of evolution.
Prokaryotic and Eukaryotic
Differentiate between prokaryotic and eukaryotic cells.
Prokaryotic:
1. Genetic material in the form of nucleoid
2. No membrane bound organelles
3. Have a cell wall
4. Ribosomes are 70s
Eukaryotic:
1. Defined nucleus
2. Have membrane bound organelles
3. Plants and fungi have cell wall.
4. Ribosomes are 80s
What is the cell capsule in prokaryotic cells made up of?
Polysaccharides
What is the function of cell capsule in prokaryotic cells?
- Protection
- Attachment- allow cells to cling to each other or their environment
- Prevents the cell from drying out
What is the cell wall in prokaryotic cells made up of?
Peptidoglycans
What is the cell wall in plants made up of?
Cellulose
What is the cell wall in fungi made up of?
Chitin
What is the function of a cell wall?
- Provides shape and structure to the cell
- Prevents the cell from bursting with excess water
- Protection
What are pilli?
Appendages used for attachment.
What are the different types of pilli?
- Sex pilli- joins cells to allow DNA transfer (conjugation)
- Type IV pilli- allows movement of cells
What is flagellum?
Long appendages to propel in water
What is the function of plasma membrane?
- Allows materials to move in and out of the cell (semi permeable)
- Participates in cell recognition
- Has receptors that receive hormonal and other signals.
- Binds cells together through interlocking sites.
- Provides protection and encloses cytoplasm.
- Has binding sites for enzymes
- Has anchoring sites for filaments of cytoskeleton.
What is the structure of a plasma membrane?
Phospholipid bilayer
