Chapters 1-3 Flashcards
homeostenosis
decreased ability to maintain homeostasis under stress
4 major types of biomolecules
carbohydrates lipids proteins nucleotides
3 major body cavities
cranial thoracic abdominopelvic
TBW
women= .5x body weight men= .6x body weight ICF volume = 2/3 TBW ECF volume = 1/3 TBW interstitial fluid = 3/4 ECF plasma fluid = 1/4 ECF
3 main types of lipids
phospholipids sphingolipids cholesterol
MICELLES
small droplets consisting of single layer of phospholipids arranged so interior is filled with hydrophobic fatty acid tails; important in digestion
LIPOSOMES
larger spheres with bilayer phospholipid membrane, hollow core that can be filled with aqueous solution (?drug delivery thru skin)
integral proteins
only way they can be removed is by disrupting the membrane; include some enzymes and structural proteins; trans-membrane and lipid-anchored
peripheral proteins
attach via noncovalent bonds; can be separated by chemical methods that do not disrupt the membrane. Includes some enzymes & structural binding proteins that anchor the cytoskeleton.
transmembrane proteins
are also called membrane-spanning proteins When a protein traverses the membrane more than once, loops of the AA chain protrude into the cytoplasm and the extracellular spaces
Lipid anchored proteins
covalently bound to lipid tails inserted into the bilayer GPI (glycosphosphatidylinositol) anchor
cell membrane glycocalyx
Most membrane carbohydrates are sugars attached to proteins or lipids Found exclusively o the surface of the cell where they form a glycocalyx Play a role in immune response Cell-cell commnication and signal transduction Viral receptors ABO blood groups (bases on number and composition of sugars attached to sphingolipids)
4 primary tissue types
Epithelium Connective tissue Muscle Neural
Extracellular matrix
ECM Extracellular material that is synthesized and secreted by a cell of a tissue 2 basic components: Proteoglycans proteins covalently bound to polysaccharide Insoluble protein fibers collagen, fibronectin, laminin
Cadherins
calcium dependent; cell-cell junctions such as desmosomes
Integrins
cell-matrix junctions; have a role in cell signaling
immunglobulin superfamily CAM
NCAM’s (nerve CAM’s); responsible for nerve growth during development
Selectins
temporary cell-cell adhesions
Gap junctions
rapid cell-cell communication connexins open and close to regulate transport of ions and small molecules Allow chemical and electrical signals to pass from cell to cell rapidly Once thought to be only in muscle and nerve cells, found in: liver, pancreas, ovary and thyroid
occluding tight junctions
restrict the movement of material between cells Adjacent cell membranes partially fuse via specialized proteins (claudins, occludins) Examples: blood brain barrier kidney and GI tract
anchoring junctions
Attach cells to each other or to matrix Cadherins (cell-cell) Integrins (cell matrix) Also involved in cell-signaling
Fluid filled compartments
Cardiovascular system (heart and blood vessels) CSF (brain and spinal cord) Eyes (aqueous and vitreous humors) Pericardial and pleural sac
lumen
The interior of any hollow organ for some organs, the lumen can be an extension of the external environment
body compartments are divided by
the cell membrane
functions of the cell membrane
- physical barrier 2. regulates exchange with the environment 3. communication between cell & environment 4. structural support
the cell membrane is lipid and protein
the more metabolically active the cell is, it generally has more protein
Fluid mosaic model
protein synthesis
translation
