Unit 2: Cellular Physiology Flashcards
(54 cards)
What are the three main components of the cell?
-A plasma membrane, nucleus and cytoplasm
What is the purpose of the Plasma Membrane?
Oily layer that separates the ICF from the ECF.
-Allows for selective permeability of substances
What constitutes the Nucleus?
- Double membrane layer that has nuclear pores which allow for selective materials in and out of the nucleus
- Contains DNA for protein synthesis & to hold genetic information
What is mRNA?
Delivers the coded message to ribosomes which “read” mRNA templates and translate it into a proper amino acid sequence
What is rRNA?
-An essential component of ribosomes.
What is tRNA?
-Transfers the appropriate amino acids within the cytoplasm to their designated site in the synthesizing protein.
What is the cytosol?
Semi-fluid medium in which many biochemical events occur within. Contains all the macromolecules.
What is the cytoskeleton?
- Protein network that gives the cell its shape, provides internal organization and regulates its various movements.
- ->Consists of microfilaments, intermediate filaments and microtubules.
What are organelles?
Compartments within the cells that carry out specific tasks. There are 6 organelles:
ER, golgi, lysosomes, peroxisomes, mitochondria and vaults.
Components of the RER?
- Studded with ribosomes, so it undergoes protein synthesis.
- Proteins can be transported within the cell or secreted elsewhere throughout the golgi.
Components of the SER?
-Does not contain ribosomes.
Primarily serves as a central packaging and discharge site for molecules to be transported to the ER.
-Sends molecules to transport vesicles where they can be distributed.
What are vesicles?
Cargo containers
What is the main purpose of the SER?
Lipid Synthesis
What is the SER in muscle cells?
The Sarcoplasmic Reticulum which stores calcium.
What is the Golgi complex?
The golgi complex is composed of stacks that bind with vesicles, sort and transport molecules appropriately.
–>Raw materials are turned into finished products and sorted accordingly. Each product is marked with a docking marker to ensure it gets sorted correctly.
Define exocytosis?
The mechanism of extruding substances to the cell’s exterior.
“Secretion of contents”
Where do secretory vesicles bind to cells?
ONLY to the plasma membrane and not into the actual cells internal membrane.
What are v-snares & t-snares?
After vesicles shed coating proteins, docking markers are exposed, which can bind with protein markers on the target membrane.
What are lysosomes?
Membrane enclosed sacs that contain powerful hydrolytic enzymes, capable of lysing and destroying cells.
- Form in the Golgi Complex
- Like a cell’s miniature digestive system
What is Phagocytosis?
- A type of endocytosis
- In taking of material by the cell by engulfing the foreign matter.
- ->Most commonly occurs in WBC’s.
What is Pinocytosis?
“Cell Drinking”
- A small droplet of extracellular fluid is internalized.
- The plasma membrane drips inward, which seals at the surface around the ECF contents.
What is the name of the protein responsible for pinching off Endocytotic vesicles?
Dynamin
Explain Receptor- Mediated Endocytosis?
- Intake of material by receptor- protein binding.
- Membrane sinks and seals at the surface.
- Highly selective, but allows intake of large molecules from the environment.
What are psuedopods?
- “False Feet”
- Surround the material to be engulfed and trap it within an internalized vesicle.
- ->Lysosomes then bind with the vesicle and break down the foreign matter.
