UNIT 1.3 Structural and Functional Organization of the Body Flashcards
DESCRIBE the structural and functional organization of the cells of the human body
NAME the three main parts of a cell
plasma membrane, cytoplasm, and nucleus
DEFINE the function of the plasma membrane
- Flexible, sturdy barrier of mostly lipids and proteins
DEFINE the functions of the nucleus
- spherical oval structure most prominent feature of a cell
- contain most of cells hereditary units
DEFINE how cells differ in size and shape
200 types of cells various shapes tail (flagellum) disc shape long spindle shape can contain microvilli have long extensions
Cell biology
- study of cellular structure and function
cell
living structural and functional unit of the body
Plasma membrane
- forms flexible outer surface; separating outside from inside
- regulates flow of materials into and out of the cell
- plays key role in communication among and between cells and external environment
two components of Cytoplasm
cytosol and organelles
Cytosol
- liquid portion of cytoplasm
- mostly water with dissolved solutes and particles
Organelles
- membrane-bound structures with specific structures and functions
Nucleus
- largest organelle
- acts as the control center
- contains the organisms genes
- control cell structures and activities
Lipid bilayer
- basic framework of the plasma membrane
three types of lipid molecules
- Phospholipids
- Cholesterol
- Glycolipids
Phospholipids
lipids that contain phosphorus
Glycolipids:
- lipids attached to carbohydrates
Two types of membrane proteins
- Integral
- Peripheral
Integral proteins
extend into or through the lipid bilayer
Peripheral proteins
- loosely attached to the interior or exterior surface of the membrane
glycoproteins
- peripheral proteins attached to carbohydrate
Plasma Membrane Function
- Selectively permeable: allows some substances to move into and out of cell, but restricts others
2 types of proteins in a membrane
integral
peripheral
Intracellular Fluid (ICF)
inside body cells
3 main parts of a cell
plasma membrane
cytoplasm
nucleus
cytoplasm
consists of all cellular contents between plasma membrane and nucleus
glyco means
carbohydrate
type of molecules that can not pass through plasma membrane
large molecules such as proteins
enzymes
speed up specific chemical reactions
where is 2/3 of fluid in the body
intracellular fluid
interstitual fluid
microscopic spaces between cells of the tissues
plasma
Extracellular fluid in the blood vessels
lymph
Extracellular fluid in the lymphatic vessels
solute
material dissolved in a fluid
solvent
dissolving fluid
concentration
amount of a solute in the solvent
concentration gradient
difference between high and low concentrations
kinetic energy
energy in motion
- will move down concentration gradient
active transport
usually in form of ATP
-pushes uphill against concentration gradient
passive transport and 3 types
only kinetic energy
- down concentration gradient
- diffusion, facilitated diffusion, and osmosis
simple diffusion
movement of substances from higher concentration gradient to lower until equilibrium is reached
lipid soluble substances that move by simple diffusion
oxygen carbon dioxide fatty acids steroids' water urea
facilitated diffusion
molecules (such as glucose) bind to a integral protein on one side of membrane and released on the other
osmosis
passive movement of water through a selectively permeable membrane from area of higher water concentration to lower water concentration
isotonic
- solution with equal concentrations of solute and solvent on either side
- water enters and leaves at same rate
- cell maintains shape and volume
hypotonic
- solution in ECF has low concentration solute and high concentration of solvent (water)
- cells (such as RBC) to rupture as water moves into cell
hypertonic
- solution in the ECF has a high concentration of solute and a low concentration of solvent (water)
- cells (such as RBC) to shrink (crenate) as water moves out of cell
sodium- potassium pump (Na+ K+)
keeps high levels of K+ in cells ICF, and high concentration of Na+ outside cell in ECF
- critical for nerve ad muscle function
types of active transport
Na+K+ pump endocytosis phagocytosis bulk-phase endocytosis exocytosis
endocytosis
substances surrounded and enclosed by a piece of the plasma membrane forming a vesicle that bring it into cell
2 types of endocytosis
phagocytosis and bulk-phase endocytosis
phagocytosis
cell eating
- how white blood cells destroy bacteria
bulk-phase endocytosis
ingestion of tiny droplets of extracellular fluid. vesicle surrounds ECF
- aka pinocytosis “cell drinking”
exocytosis
movement of substances out of a cell resulting in secretion of the substance into the ECF
oocyte
largest cell
- 140 micrometers
- barely visable to unaided eye
red blood cell
disc shaped
8 micrometers
large surface area
pass oxygen
sperm cell
tail (flagellum) used for locomotion
smooth muscle cell
long, spindle shape
shortens as it contracts
narrows or widens
blood flow
microvilli
greatly increases surface area
common in epithelial cells (line small intestine)
speeds the absorption of digested foods
nerve cells
long extensions that conduct nerve impulses