Cellular Biology Flashcards
What are the 8 specialized cellular functions?
- Communication
- conductivity
- metabolic absorption
- movement
- respiration
- reproduction
- secretion
- excretion
What organelle builds proteins?
Ribosome
Function of rough endoplasmic reticulum
synthesis, folding and transport of protein components
Function of smooth endoplasmic reticulum
synthesis of steroid hormones and a variety of reactions required to remove toxic substances
Function of golgi complex
processing and packaging proteins into secretory vesicles that break away from the gonlgi and migrate to a variety of intra & extra cellular destinations including plasma membrane
2 functions of lysosomes
-contain digestive enzymes that break substances into basic forms (amino acids, fatty acids and carbs).
-cellular injury leads to release of lysosomal enzymes digesting self. They also serve as a signaling hub in a network for cellular adaptation.
Function of Peroxisomes
contain several enzymes that either produce or use hydrogen peroxide and their reactions detoxify waste products
Function of mitochondria
Metabolic machinery needed for cellular energy metabolism. enzymes of the respiratory chain (electron transport chain) generate ATP
What is the structure of the plasma membrane
lipid bilayer studded with various proteins. Carbohydrates contained within the plasma membrane are generally bound to membrane proteins (glycoproteins) or lipids (glycolipids)
Amphipathic
polar- hydrophilic at one end and hydrophobic at the other
Define trafficking
proteins synthesized by the ribosome translocate into different areas of the cell.
Plasma Protein function
performs most of the membranes tasks. Recognition, binding, moving substances into and out of the cell, pores and transport channels, enzymes that drive pumps or maintain ion concentrations, cell surface makers, cell adhesion molecules and catalysts of chemical reactions
What is proteostasis
state of cell balance of the processes of protein synthesis, folding and dehydration.
What organelles are in the proteostasis network
ribosomes, chaperones, and protein breakdown or proteolytic systems. Issues with this system are associated with disease
What is the glycocalyx
-carbohydrate coating on the outside of the cell that protects it from mechanical damage and creates a slimy surface that assists mobility.
-these carbohydrates also function in cell to cell recognition and adhesion
What are the three ways cells are held together
- extracellular membrane
- cell adhesion molecules in the cells plasma membrane
- specialized cell junctions
What is the extracellular matrix
secreted by cells and is a meshwork of fibrous proteins in a gel like substance. provides a pathway for diffusion of nutrients, wastes and other water soluble substances. It helps regulate cell growth, movement and differentiation
What are the extracellular matrix macromolecules
1.fibrous structural proteins (collagen and elastin)
2. adhesive glycoproteins
3. proteoglycans and hyaluronic acid
What is a basement membrane
special type of extra cellular matrix that is very thin, tough, and flexible. It lies under the epithelium of many organs. Also called basal lamina
What are the 4 cell adhesion molecule families, and their function
- integrins- bind to ECM- collagen, fibronectin, vitronectin, and fibrinogen
- cadherins- cell to cell- calcium dependent
- selectins- cell to cell- carbs
- IgSF (immunoglobulin superfamily)- cell to cell-
What are symmetric junctions
tight junctions, belt desmosome, desmosomes and gap junctions
What are asymmetric junctions
hemidesmosome
What are the three main ways cells communicate
- protein channels (gap junctions)
- display receptors that affect intracellular processes or other cells in direct physical contact
- use receptor proteins inside the target cell
What are the primary modes of intercellular signaling (5)
- contact dependent
- paracrine
- hormonal
- neurohormonal
- neurotransmitter
What is signal transduction
signals or instructions from ECM chemical messengers conveyed to the cells interior for execution.
deprivation of appropriate signals triggers apoptosis.
Catabolism vs anabolism
Catabolism is energy releasing and anabolism is energy using
Phases of catabolism
- digestion
- glycolysis and oxidation
- citric acid cycle
What are the passive transport mechanisms
- diffusion
- filtration
- osmosis
Diffusion
solute from high concentration to low
Filtration
Water and solutes through a membrane from pushing pressure on one side
Osmosis
water movement from lower solute concentration to higher
Oncotic pressure, osmotic pressure, and hydrostatic pressure
Oncotic- overall osmotic effect of colloids such as plasma proteins
Osmotic- the amount of hydrostatic pressure needed to oppose the osmotic movement of water
hydrostatic- force of water pushing against a cellular membrane
Pinocytosis
type of endocytosis where fluids and SOLUTE molecules are ingested though the formation of small vesicles
What are the 4 phases of the cell cycle
- G1 (Gap)- between M phase and start of DNA synthesis
- S phase (synthesis)- DNA synthesis occurs
- G2 (between completion of DNA synthesis and the next phase where RNA protein synthesis occurs
- M phase (mitosis)- both nuclear and cytoplasmic division
What are the two classes of trigger regulatory molecules that determine a cells progression though the cell cycle
- CDKs- cyclin dependent kinases
- Cyclins
What three factors maintain cellular organization of tissues
- Recognition and cell communication
- selective cell to cell adhesion
- memory
What are the 4 basic tissue types
- Epithelial
- Muscle
- Nerve
- Connective
