chapter 3 anatomy and physiology mcgraw hill 10th edition

cytology

scientific study of cells, foundation for all biological understanding of life

cellulae

little cells (hooke)

Cells theory

all living organisms are make of up one or more cells

cells are the basic structural and functional units of all living things

all activities of an organism stem from the activities of its consistent cells

all cells arise from pre-existing cells, not from non-living matter and they pass hereditary information from generation to generation

types of cells

squamous, cuboidal, columnar, polygonal, stellate , spheroidal to ovoid, discoidal, fusiform, fibroid

squamous cell

a thin flat scaly shape, often with a bulge where the nucleus is.

Aline the esophagus and air sacs of the lungs, form the epidermis of the skin

Cuboidal

squarish-looking in frontal sections and about equal in height and width;

liver cells are a good example

columnar cells

distinctly taller than wide, such as the inner lining cells of the stomach and intestines

polygonal cells

having irregular angular shapes with four, five, or more sides.

densely packed cells of many glands

Stellate

having multiple pointed processes projecting from the body of a cell, giving it a somewhat starlike shape.

The cell bodies of many nerve cells are.

spheroidal to ovoid cells

round to oval,

as in egg cells and white blood cells

discoidal

disc-shaped (red blood cells)

fusiform

spindle shaped, elongated with a thick middle and tapered needs.

smooth muscle cells

Fibrous

long, slender, and threadlike

as in skeletal muscle cells and axon (nerve fiber) cells

micrometer

most useful until of measure for designing cell sizes

Cytoplasm

contents of a cell between its plasma and its nuclear envelope, consisting of cytosine, organelles, and inclusions and the cytoskeleton

Transmission Electron Microscope (TEM)

uses an electron beam in place of light to form high resolution, 2D images of ultra thin slices of cells or tissues, capable of extremely high magnification

resolution

the ability to reveal detail, to distinguish small, close together objects from each other

empty magnification

if an enlargement fails to reveal any more useful detail

Scanning Electron Microscope (SEM)

uses an electron beam in place of light to form high resolution 3D images

cell membrane is made up of

phospholipid bilayer (protein and lipids)

positions of the cell

basal (bottom)

lateral (middle)

apical (top)

cell membrane

membrane that encloses a cell and the traffic of molecules in and out of cells

cytoplasm

crowded with fibers, tubules, passages, and compartment

cytoskeleton

supportive framework of protein filaments and tubules

organelles

diverse structures that perform various metabolic tasks for the cell

inclusions

foreign matter or stored cell products

cytosol

a clear, featureless, gelatinous colloid in which organelles and other internal structures of a cell are

ICF (intracellular fluid)

the fluid contained in the cells, one of the bodies major fluid components

Extra cellular fluid

any body fluid that is NOT contained in the cells

examples: blood, lymph and tissue fluid.

plasma membrane

defines the boundaries of the cell, governs it's interactions with other cells and it controls the passage of materials into and out of the cell

intercellular face of the membrane

faces the cytoplasm

extracellular face of the membrane

faves outward

98% of membrane molecules are

lipids

types of membrane proteins

transmembrane and peripheral

transmembrane protein

An integral protein that extends through a plasma membrane and contacts both the extracellular and intracellular fluid.

pass completely through the phospholipid bilayer, protruding from it on both sides

peripheral proteins

a protein of the plasma membrane that clings to its intracellular or extra cellular surface but does not penetrate

the phospholipid bilayer

Functions of membrane proteins

Receptors

enzymes

channel proteins

carriers

cell identity markers

cell adhesion molecules

membrane proteins receptors

receive chemicals

enzymes

carry out final stages of starch and protein digestion

channel proteins

passages that allow water and hydrophilic solutes to move through the membrane

channel

is a tunnel that passes through a complex of multiple proteins or between subunits

leak channel

always open and allow materials to pass through continuously

gates (gates channels)

open and close under different circumstances and allow solutes through at some times but not others

ligand gated proteins

channel that opens or closes when other chemical (ligand) binds to it, enabling the ligand to determine when substances can enter or leave the cell.

respond to chemical messengers

voltage gated channels

open and close in response to changes in electrical potential across the plasma membrane

mechanically gated channels

open and close in response to physical deformation of receptors

Channelopathies

diseases and disorders that are the result of ion channel dysfunction

membrane protein: carriers

transmembrane proteins that bind to glucose, electrolytes and other solutes and transfer them to the other side of the membrane.

cell identity markers

glycoproteins acting as identification tags. Enable the immune system to tell which cells belong to one's body and which are foreign invaders

cell adhesion molecules

cells adhere to one another and to extracellular material through membrane proteins

second messengers

A chemical that is produced within a cell (such as cAMP) or that enters a cell (such as calcium ions) in response to the binding of a messenger to a membrane receptor, and that triggers a metabolic reaction in the cell

G protein

A protein of the plasma membrane that is activated by a membrane receptor and, in turn, opens an ion channel or activates an intracellular physiological response; important in linking ligand-receptor binding to second-messenger systems.

adenylate cyclase

An enzyme of the plasma membrane that makes cyclic adenosine monophosphate (cAMP) by removing two phosphate groups from ATP; important in the activation of the cAMP second-messenger system.

cyclip AMP

activate protein kinase enzymes- transfer phosphate groups from ATP to other proteins

Kinases (phosphokinase)

Enzymes that catalyze the transfer of phosphate groups from ATP to acceptor molecules.

process of second messengers

ex:

ep

surface receptor

g protein (actv. by mem. recept.)

opens ion channel

g protein signals Adenylate cyclose

AC removes 2 phos. groups

AC concerts 2 phos. group +cAMP

cAMP (2nd mess) is created

cAMP activates cytoplasmic enzymes

kinases is activated

kinases add phos. group to other cellular enzymes

some enzymes activate some deactivate

whole process triggers a great variety of physiological changes in the cell

Glycocalyx

A layer of carbohydrate molecules covalently bonded to the phospholipids and proteins of a plasma membrane; forms a surface coat on all human cells.

external to the plasma membrane, fuzzy coat

human blood types are determined by

glycolipids

Glycocalyx is composed of

glycoproteins and glycolipids

functions of glycocalyx

protection,

immunity to infection,

defense against cancer,

transplant compatibility,

cell adhesion,

fertilization,

embryonic development

glycocalyx protection

cushions the plasma membrane and protects it from physical and chemical injury

Glycocalyx (IMMUNITY TO INFECTION)

Enables the immune system to recognize and selectively attack foreign organisms

Glycocalyx (DEFENSE AGAINST CANCER)

changes in the glycocalyx of cancerous cells enable the immune system to recognize and destroy them

Glycocalyx (TRANSPLANT COMPATIBILITY)

Forms the basis for compatibility of blood transfusions, tissue grafts and organ transplants

Glycocalyx cell adhesion

Binds cells together so tissues do not fall apart

glycocalyx fertilization

enables sperm to recognize and bind to eggs

Glycocalyx (EMBRYONIC DEVELOPMENT)

Guides embryonic cells to their destinations in the body

extensions of the cells device aid in

absorption

movement

sensory process

Microvilli

an outgrowth of the plasma membrane that increases the surface area of the cell and functions in absorption and some sensory process

are extensions of the plasma membrane that serve primarily to develope the cells surface area

best developed microvilli in cells is specialized for?

absorption, such as epithelial cells of the intestines and kidney

brush border

a fringe of microvilli on the apical surface of an epithelial cell, serving to enhance surface area and promote absorption

Actin

stiff filaments of protein that attach to the inside of the plasma membrane

Cilia

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

power stroke (cilia)

the propulsive movement of a cilium, bending stiffly forward pushes along

recovery stroke (cilia)

the non-propulsive movement of a cilium

axoneme

central core of cilia or flagellum, composed of micro tubules.

Circular 9+2 structure

Microtubules

Spiral strands of protein molecules that form a tubelike structure. One tube has 2 dynein

dynein arms

A motor protein involved in the beating of cilia and flagella and in the movement of molecules and organelles within cells, as in retrograde transport in a nerve fiber.

primary cilia

cannot move

Flagellum

A long, hairlike structure that grows out of a cell and enables the cell to move.

flagellum example

sperm

pseudopods

are cytoplasm filled extensions of the cell varying in shape

pseudopod examples

amoeba

macrophages

neutrophils