Cells And Organelles Flashcards
(27 cards)
What is the function of a ribosome?
Makes proteins
-Ribosomes are made of RNA .
What role does cholesterol play in the cell membrane?
Regulates fluidity
What are the types of membrane proteins?
- Carrier Proteins
- Channel Proteins
- Transport Proteins
What is the primary function of the nucleus?
Contains DNA and coordinates cell activities
-In prokaryotes, the nucleoid contains genetic material.
What does the nucleolus do?
Site of ribosome synthesis
What is the main function of the smooth endoplasmic reticulum?
Synthesizes lipids and steroid hormones
What is the cytoplasm?
Fluid-filled area for metabolic activities
What are mitochondria known for?
Making ATP and fatty acid catabolism
What is the function of lysosomes?
Break down nutrients, bacteria, and cell debris, involved in apoptosis, made by golgi
What is passive transport?
Movement without ATP, down the gradient
Ex: simple diffusion, osmosis, and facilitated diffusion.
What is active transport?
Movement using ATP, against the gradient
Ex: Amino acids
What is phagocytosis?
The plasma membrane invaginates around solid undissolved substances like bacteria.
What are the components of the cytoskeleton? And what does it do?
- Microtubules
- Intermediate filaments
- Microfilaments
-maintains cell shape and movement.
What distinguishes prokaryotic cells?
- No nucleus
- Single circular DNA
- Ribosomes (70S)
Prokaryotes have cell walls made of peptidoglycan or polysaccharides.
What is a hypertonic solution?
Higher solute concentration
-lose water and shrink.
What is the function of anchoring junctions?
Connects two cells together
Ex. Desmosomes
What is the role of tight junctions?
Prevents material passage between cells
They are important in the lining of the digestive tract.
What is a gap junction?
-Narrow tunnels between animal cells
They allow the passage of ions and small molecules.
Hypotonic solution
Lower solute concentrations
-cell may burst or be lysed
Isotonic
Equal solute concentration
-Normal
What are 2 main components found in plants
Cell wall: provides support
Plastids: serves various metabolic activities
Ex. Chloroplast for photosynthesis
True or false: Mitochondria have their own circular DNA and ribosomes.
True
Pinocytosis
PM invaginated around dissolved material (liquid)
Mediated endocytosis
Specific molecs called ligands bind to receptors
