PPT Notes: Chapter 3 Flashcards
hematopoeisis
process of making blood in the bone
cell layers
- simple - single layered
- stratified - two or more layers
- pseudostratified - single layered
cardiac muscle cell
long branched chain
skeletal muscle cell
no branching; multi-nucleated cell
What are the 4 principles of cell theory?
- -The cell is the basic structural and functional unit of life
- -Activity of the organism depends on individual and collective activity of cells
- -Biochemical activities of cells are dictated by subcellular structure
- -Continuity of life has a cellular basis
Cells vary greatly in what 3 areas?
size, shape and functions
All cells are composed primarily of what elements?
NCHOPS
- -Nitrogen
- -Carbon
- -Hydrogen
- -Oxygen
- -Phosphorous
- -Sulfur
All cells have the same…
basic parts and some common functions
A generalized human cell contains 3 major regions:
- -the plasma membrane
- -cytoplasm
- -nucleus
3 characteristics of the plasma membrane
- -Separates intracellular fluids from extracellular fluids
- -Plays dynamic role in cellular activity
- -Utilizes 3 common biological molecules: protein, carbohydrates and lipids in its structure
Glycolipids are… found only … function in…
- -lipids with bound carbohydrates
- -found in the outer membrane
- -function in cell signaling
*Cholesterol maintains fluidity of the membrane and is found in the lipid portion
glycocalyx
*calyx=coat
- -aka cell coat
- -fuzzy, sticky, carbohydrate
- -involved with cell recognition:
- fertilization, immunity (determines blood type), acts as adhesive between cells
tight junction
impermeable junction that encircles the cell
*found in bladder, intestine, etc
desmosome
anchoring junction scattered along the sides of cells
gap junction
a nexus (tube) that allows chemical substances to pass between cells
passive transport does not require…
energy
*the amount of E required is too small to be significant
facile
easy
Osmosis
- -passive membrane transport
- -diffusion of water across a semipermeable membrane
- -Occurs when the concentration of a solvent is different on opposite sides of a membrane
Osmolarity
total concentration of solute particles in a solution (%)
tonicity
how a solution affects cell volume
toni-
tension
isotonic
solutions with the same solute concentration as that of the cytosol
iso-
same
hypertonic
solutions having greater solute concentration than that of the cytosol
hypotonic
solutions having lesser solute concentration than that of the cytosol
crenate
to shrivel up
Which way does water move in the concentration gradient?
always moves down
Osmotic imbalance on living red blood cells:hypertonic and hypotonic
- -crenation in hypertonic solution
- -hemolysis in hypotonic solution
Filtration
=Passive membrane transport=the passage of water and solutes through a membrane by hydrostatic pressure
- -pressure gradient pushes solute-containing fluid from higher-pressure area to a lower-pressure area
- -essential for proper urine formation
Active transport
- -Uses ATP (energy) to move solutes across a membrane
- -requires carrier proteins (pumps)
What are the two active transport systems?
Symport system
- two substances are moved across a membrane in the same direction (cat walks in, you walk in)
Antiport system
- two substances are moved across a membrane in opposite directions (cat walks in, you walk out)
What kind of pump is Na+K+ pump
antiport
*salt on a banana
Primary active transport
hydrolysis of ATP phosphorylates the transport protein causing conformational change
Secondary active transport
use of an exchange pump (such as Na+K+ pump) indirectly to drive the transport of other solutes
-uses the gradient established by the primary transport
*Na+K+ = salt on a banana
Vesicular transport
transport of large particles and macromolecules across plasma membranes within a vesicle
- -exocytosis moves substance from the cell interior to the extracellular space (out)
- -endocytosis enables large particles and macromolecules to enter the cell (in)
Transcytosis
moving substances into, across and out of the cell
Vesicular trafficking
moving substances from area in the cell to another within vesicles
Phagocytosis
pseudopods engulf solids and bring them into the cell’s interior
Fluid-phase endocytosis
the plasma membrane infolds, bringing extracellular fluid and solutes into the interior of the cell
Receptor-mediated endocytosis
clathrin-coated pits provide the main route for endocytosis and transcytosis
*clathrin = parking sign
Non clathrin-coated vesicles
caveolae that are platforms for a variety of signaling molecules
CAMs: Cell Adhesion Molecules
Act as:
- -anchors eg desmosomes
- -sticky arms for cellular migration
- -SOS signals for immunity
- -Mechanical sensors for local tension at the cell surface
- -Intracellular transmitters
Ribosomes
single stranded plynucleotide
- -granules containing protein and rRNA
- -site of protein synthesis
- -Free ribosomes synthesize soluble proteins
- -membrane bound ribosomes synthesize proteins to be incorporated into membranes
Rough endoplasmic reticulum
- external surface studded with ribosomes
- manufactures all secreted proteins
- responsible for the synthesis of integral membrane proteins and phospholipids for cell membranes
Smooth endoplasmic reticulum
*slippery, fats
- -tubules arranged in a looping network
- -catalyzes reactions in various organs of the body
Smooth ER catalyzation in the liver
lipid and cholesterol metabolism, breakdown of glycogen and, along with the kidneys, detoxification of drugs
Smooth ER catalyzation in the testes
synthesis of steroid-based hormones
Smooth ER catalyzation in the intestinal cells
absorption, synthesis and transport of fats
Smooth ER catalyzation in skeletal and cardiac muscle
storage and release of calcium
Golgi apparatus
- -stacked and flattened membranous sacs
- -operates as the cell’s “chop shop”
- -functions in modification, concentration and packaging of proteins
Describe the process proteins go through when being modified by the Golgi apparatus
- -Transport vessels from the ER fuse with the cis face (receiving side) of the Golgi apparatus
- -proteins then pass through the Golgi apparatus to the trans face (releasing side)
- -secretory vesicles leave the trans face of the Golgi stack and move to designated parts of the cell
Nucleus
*most important structure
- -contains nuclear envelope, nucleoli, chromatin, and distinct compartments rich in specific protein sets
- -gene-containing control center of the cell
Stages of mitosis (nuclear division)
PMAT
- -Prophase
- -Metaphase
- -Anaphase
- -Telophase
Prophase
- -Asters are seen as chromatin condenses into chromosomes
- -nucleoli disappear
- -centriole pairs separate and the mitotic spindle is formed
Metaphase
- -Chromosomes cluster at the middle of the cell with their centromeres aligned at the exact center, or equator, of the cell
- -This arrangement of chromosomes along a plane midway between the poles is called the metaphase plate
Anaphase
- -Centromeres of the chromosome split
- -Motor proteins in kinetochores pull chromosomes toward poles
Telophase/Cytokinesis
New sets of chromosomes extend into chromatin
- -New nuclear membrane is formed from the rough ER
- -Nucleoli reappear
- -Generally cytokinesis completes cell division
Protein synthesis
- -DNA serves as master blueprint for protein synthesis
- -Genes are segments of DNA carryig instructions for a polypeptide chain
- -Triplets of nucleotide bases form the genetic library
- -Each triplet specifies coding for an amino acid
Central Dogma
Information transfer from DNA to RNA to Protein
