Cellular Form & Function

________ is the simplest structural and functional unit of life

cell

Cells come only from

pre-existing cells

Squamous =

flat and thin

Polygonal =

irregularly angular with 4 or more sides

Cuboidal=

square

Columnar=

Taller than wide

Spheroid=

Round

Discoid=

Disc-shaped

Stellate=

Starlike

Fulsifrom=

Thick in middle, tapered at ends

Fibrous =

Threadlike

Cell growth increases _____________ faster than ___________.

volume, surface area

Basic components of cells

Plasma Membrane

Cytoplasm

Cytoskeleton

Organelles

Inclusions Cytosol

Intergrins are

membrane proteins that mediate cell adhesion

plasma membrane function

selective permeability- maintains intracellular environment

The plasma membrane is ______% lipids

98

glycolipids contribute to

glycocalyx- carbohydrate coating on cell surface

transmembrane proteins

Integral proteins that pass completely through membrane

Most are glycoproteins

Peripheral proteins

Extrinsic proteins that adhere to membrane surface

second messenger system

Chemical messenger (epinephrine) binds to a surface receptor

Receptor activates G protein

G protein binds to adenylate cyclase which converts ATP to cAMP(2nd messenger)

cAMP activates a kinase in the cytosol

Kinases activates or inactivates other enzymes triggering

physiological changes in cell (such as breaking down glycogen for quick energy)

Channel proteins

Open or close

Nongated ion channels are always

Open

Gated ion channels can be

open or closed

voltage-gated ion channels

open when there is a change in charge across the plasma membrane

carrier proteins

integral proteins move ions from one side of membrane to the other

________ and ______ are marker moelcules

Glycoproteins and glycolipids

In autoimmune disease, the body mistakes ______ and _______ for abnormalities and attacks them

Glycoproteins & Glycolipids

3 major roles of glycocalyx

Protection, defense against cancer, fertilization

When things go bad, oxidized LDL, inflammation, and disturbed flow patterns _______ _________ in arterial regions prone to plaque formation

Degrade glycocalyx

What does degradation of glycocalyx lead to

Increased plaque and atherosclerosis

microvili function

increase surface area for absorption

________ disorder leads to destruction of microvilli is known as ______ disease

Autoimmune, celiac

Hairlike projections that extend from the plasma membrane and are used for locomotion

cilia

__________ destroys cilia

smoking

Passive transport requires

no ATP

Active transport requires

ATP

Filtration depends on 2 major things:

Osmotic gradiant and pressure

_____ moves solutes from an area of higher concentration to lower concentration

Diffusion

Diffusion of water (solvent) through a selectively permeable membrane

osmosis

Tonicity is the ability of a solution to

affect fluid volume and pressure within a cell

uniporters, symporters, antiporters

Uniporters - move one substance at a time

Symporters - move two substances in the same direction

Antiporters - move two substances in opposite directions

When the concentration of x molecules outside the cell is low, the transport rate is

Low

When more molecules are present outside the cell, as long as enough carrier proteins are available, ______ molecules can be transported; thus, the transport rate _______.

More, increases

Saturation of carrier proteins

When all of the proteins are bound to their ligands, they are saturated and the rate of transport is at its maximum.

Example of saturation of a carrier protein

If there is excess glucose, the sodium-glucose transporter (SGLT) carrier proteins become overwhelmed, and glucose remains in the urine

Transport of solute across membrane down its concentration gradient

Facilitated diffusion

______ diffusion requires no atp

Facilitated

examples of facilitated diffusion

Glucose and aquaporins

Transport of solute across membrane up (against) its concentration gradient

active transport

______ transport requires ATP

active

examples of active transport

Na/K exchange pump

Glucose and amino acids are actively transported from the intestinal lumen into intestinal cells, even when concentrations are low

Functions of Na+-K+ Pump

secondary active transport, regulation of cell volume, maintenance of a membrane potential, and heat production

Example of Na-K pump

Digoxin

example of secondary active transport

sodium glucose transporter moves glucose into cells against its concentration gradient by using the energy from sodium moving down its electrochemical gradient

exocytosis vs endocytosis

Exocytosis -transport out of cell

Endocytosis -transport into cell

Vesicular transport uses

ATP

Cells goal

-what are proteins, what is a phospholipid bilayer, how does cholesterol effect cell structure