Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
50 Cards in this Set
- Front
- Back
Cells
|
coined by Robert Hooke in 1665; describes the individual units observed in thin sections of cork
|
|
Cell Theory
|
cells are the basic building blocks of all plants and animals; come from division of pre-existing cells; smallest units that perform all vital physiological functions; maintains cellular homeostasis
|
|
Homeostasis of body
|
determined by homeostasis of the cells; combined and coordinated efforts of cells give tissues, organs, organ systems, and organisms homeostasis
|
|
Classes of Cells
|
sex cells
somatic cells |
|
Sex cells
|
germ cells; reproductive cells; sperm cells in males; oocytes (ova or eggs) in females
|
|
Somatic cells
|
soma=body; all non-sex cells of the body
|
|
Extracellular fluid
|
surrounds cells in human body; means outside of cell
|
|
Interstital Fluid
|
extracellular fluid in tissue; means standing between
|
|
Plasma Membrane
|
aka cell membrane
sepaates cell from extracellular fluid; thin layer |
|
cytoplasm
|
inside the cell; mostly water
|
|
cytosol
|
liquid portion of cytoplasm
|
|
organelles
|
intracellular structures suspended in cytoplasm
|
|
Nucleus
|
nuclear membrane; DNA
|
|
Plasm membrane functions
|
Physical separation - inside from external fluid; Regulates exchange - controls entry of nutrients and ions and exit of waste and secretions; sensitive to environment - recepotrs respond to environment; structural support - tissue stability
|
|
Plasma Membrane contents
|
lipids
proteins carbs |
|
Phospholipid bilayer
|
2 layers; phospate = hydrophillic; lipid = hydrophobic; hydrophillic head at membrane surface near tissue fluid and cell fluid; hydrophobic tals on inside away from fluid
|
|
Membrane Proteins and functions
|
float in phospholipid bilayer of plasma membranes;
Functions: anchors, recognition, enzymes, receptors, carriers, channels |
|
Anchors
|
mp; attach to cytoskeleton in cytoplasm; attach to extracellular filament or to other cells
|
|
Recognition
|
mp; self v. non-self
- immune system |
|
Enzymes
|
mp; catalyze reactions
|
|
receptors
|
mp; bind to ligands
- triggers changes |
|
Carriers
|
mp;binds solutes and carries them across plasm membrane; may require energy from ATP
|
|
Channels
|
mp; pores; passageway for water and ions; may be specific
|
|
Membrane Carbs
|
small %; glycocalyx; lubrication; protection; sticky - locomation- anchor; specificity; recognitino
|
|
Plasma Membrane characteristics...
|
an effective barrier; continuous, uniform; has selective permeability
|
|
Selective Permeability
|
determines what can either enter or exit the membrane
|
|
Types of Passage across the membrane
|
passive
active |
|
Types of Passive transport across the membrane
|
diffusion; osmosis; facilitated diffusion
|
|
transports that require ATP (energy)
|
active
secondary active vesicular transport - endocytosis - exocytosis |
|
Endocytosis
|
receptor-mediated endocytosis
pinocytosis phagocytosis |
|
Diffusion
|
passive;
ions and molecules; movement from area of high concentration to area of low concentration; reduces the concentration gradient |
|
Concentration Gradient
|
difference between the high and low concentration
|
|
Rates of Diffusion
|
- increases with increase in concentration gradient
- increases as temp increases - increases as molecule size decreases - increases as distance decreases - increases with electrical forces |
|
Osmosis
|
passive;
diffusion of water molecules; moves from area of high water concentration to area of low water concentration; equilibrium |
|
Osmotic Pressure
|
force with which pure water moves;
more force needed as number of particles dissolved in the solution increases |
|
Facilitated Diffusion
|
passive;
transports nutrients such as glucose that are not soluble in lipids and too lg. for simple diffusion; molecule binds to receptor on carrier protein; movement is in difection of concentration gradient so no ATP is required |
|
Carrier Protein
|
shapes changes and moves the molecule across the membrane
|
|
Active Transport
|
ATP provides energy; moves substances against gradient; carrier proteins = ion pumps; Na-K exchange pump
|
|
Active Transport Homeostasis
|
maintained by moving K+ back into cell and ejecting extra Na+ out of cell
|
|
Secondary Active Transport
|
does not use ATP across membrane but to maintain cell homeostasis; carrier protein moves substrate w/o regard to gradient at same time; c. gradient of 1 substance provides force for moving second subtance (free ride)
|
|
Vesicular Transport
|
transporting bulk; membranes are moved in sm. sacs made of membrane (vesicles)
|
|
Types of Vesicular Transport
|
endocytosis
exocytosis |
|
Endocytosis
|
moved into cell; extracellular materials packaged in vesicles; requires ATP
|
|
types of endocytosis
|
receptor-mediated endocytosis
pinocytosis phagocytosis |
|
Receptor-mediated endocytosis
|
materials bind to recognition receptors on cell surface;
ex. cholesterol and iron |
|
Process of receptor-mediated endocytosis
|
1. recepters are glycoprotein and bind to ligands
2. receptors w. bound ligands clust together 3. pinches off into coated vesicle 4. coated vesicle fuses w. lysosomes that contain digestive enzymes 5. digestive enzymes free ligands which enter cytosol by diffusion |
|
Ligands
|
specific target that receptors of receptor-mediated endocytosis bind to
|
|
Pinocytosis
|
endocytosis; cell drinking; vesicles filled w. extracellular fluid; no receptor
|
|
Phagocytosis
|
endocytosis; cell eating; cells form pseudopods that surround solid to be brought into the cell; may be as large as the cell; phagosome vesicle fuses with lysosome and is digested by enzymes; ex. white blood cell destroying bacteria
|
|
Exocytosis
|
vesicle inside the cell fuses with plasma membrane; releases contents; homrones; waste
|