[anatomy] chapter 3 - cells and tissues

200

the human body houses over ___ different cell types

size, shape, and function

cells vary in this

1/12,000 of an inch to over 1 yard (nerve cells)

cells vary in length from...

specialized function

cell shape reflects its...

fibroblast cells and erythrocyte cells

cells that CONNECT body parts

fibroblast

secretes cable-like fibers

erythrocyte (red blood cell)

carries oxygen in the bloodstream

epithelial cells

cells that COVER AND LINE body organs

epithelial cells

packs together in sheets; intermediate fibers resist tearing during rubbing or pulling

skeletal muscle and smooth muscle cells

cells that MOVE organs and body parts

skeletal muscle and smooth muscle cells

contractile filaments allow cells to shorten forcefully

fat cells

cells that STORE nutrients

fat cells

lipid droplets stored in the cytoplasm

white blood cells (such as the macrophage, a phagocytic cell)

cells that FIGHT DISEASE

white blood cells

digests infectious microorganisms

nerve cells (neurons)

cells that GATHER INFORMATION AND CONTROL body functions

nerve cells

receives and transmits messages to other body structures

oocyte cell and sperm cell

cells of REPRODUCTION

oocyte (female)

largest cell in the body; divides to become an embryo upon fertilization

sperm (male)

built for swimming to the egg for fertilization; flagellum acts as a motile whip

nucleoplasm and cytosol

intracellular fluids

intracellular fluid

interior of the cell; a solution containing gases, nutrients, and salts dissolved in water

extracellular fluid

exterior of the cell; contains thousands of ingredients such as nutrients, hormones, neurotransmitters, salts, and waste products

selectively permeable

the plasma membrane is a ____________________________________ barrier

passive processes and active processes

two basic methods of transport

active processes requires energy

difference between passive processes and active processes

passive processes

substances are transported across the membrane without any input from the cell

active processes

the cell provides the metabolic energy (ATP) to drive the transport process

isotonic, hypertonic, and hypotonic

type of osmosis solutions

isotonic solutions

have the same solute and water concentrations as cells and cause no visible changes in the cell

hypertonic solutions

contains more solutes than the cells do; the cells will begin to shrink

hypotonic solutions

contains fewer solutes (more water) than the cells do; cells will plump

vesicular transport

active transport process

vesicular transport

substances are moved across the cell membrane "in bulk" without actually crossing the plasma membrane

exocytosis (exit) and endocytosis

types of vesicular transport

exocytosis (exit)

bulk items are removed from the cell

endocytosis

bulk items are brought into the cell

phagocytosis and pinocytosis

types of endocytosis

phagocytosis

solids in

pinocytosis

liquids in

tissues

groups of cells with similar structure and function

epithelial, cartilage, dense connective tissue, loose connective tissue

four types of tissue

body coverings, body linings, and glandular tissue

locations of epithelial tissue

protection, absorption, filtration, secretion

functions of epithelial tissue

cover and lines body surfaces

hallmark of epithelial tissues; often form sheets with one FREE SURFACE, the apical surface, and a BASAL-anchored, regenerate easily if well-nourished; anchored surface: the BASEMENT MEMBRANE

avascular

no blood supply

simple or stratified

epithelial cell layers

simple

one layer of epithelial cell tissue

stratified

more than one layer of epithelial cell tissue

squamous, cuboidal, and columnar

shape of epithelial tissue cells

squamous

flattened like fish scales

cuboidal

cube shaped like dice

columnar

shaped like columns

simple epithelia

functions in absorption, secretion, and filtration; very thin (so not suited for protection)

simple squamous epithelium

single layer of flat cells, lines air sacs of the lungs, forms serous membranes (serosae) that line and cover organs in the ventral cavity, functions in diffusion, filtration, or secretion in membranes LOCATION: usually forms membranes

simple cuboidal epithelium

single layer of cubelike cells, functions in secretion and absorption; ciliated types of propelling mucus or reproductive cells LOCATION: common in glands and their ducts, forms walls of kidney tubules, covers the surfaces of ovaries

simple columnar epithelium

single layer of tall cells (GOBLET CELLS secrete mucus) LOCATION: lining of the digestive tract from stomach to the anus, mucous membranes (mucosae) line body cavities opening the exterior, functions in secretion and absorption

pseudostratified columnar epithelium

all cells rest on a basement membrane; single layer, but some cells are shorter than others giving a false (pseudo) impression of stratification LOCATION: respiratory tract, where it is ciliated and known as the pseudostratified ciliated columnar epithelium

stratified squamous epithelium

most common stratified epithelium, named for cells present at the free (apical) surface, which are squamous, functions as a protective covering where the friction is common LOCATIONS: the lining of the... skin (outer portion), mouth and esophagus

stratified cuboidal epithelium

two layers of cuboidal cells; functions in protection

stratified columnar epithelium

surface cells are columnar and cells underneath vary in size and shape, functions in protection, both are rare in the human body LOCATION: found mainly in ducts of large glands

transitional epithelium

composed of modified stratified squamous epithelium, shape of cells depends upon the amount of stretching, functions in stretching and the ability to return to normal shape LOCATION: the lining of urinary system organs

stratified squamous epithelium, stratified cuboidal epithelium, stratified columnar epithelium

stratified epithelial tissues

glandular epithelia

one or more cells responsible for secreting a particular product

endocrine and exocrine glands

two major gland types that develop from epithelial sheets

endocrine glands

ductless; secretions (hormones) diffuse into blood vessels) ex.) include thyroid, adrenals, and pituitary

exocrine glands

secretions empty through ducts to the epithelial surface ex.) include sweat and oil glands, liver, and pancreas (both internal and external)

connective tissue

found everywhere in the body to connect body parts, includes the most abundant and widely distributed tissues

protein, support, binding

functions of connective tissue

variations in blood supply, some types are vascularized, some have poor blood supply or are avascular (none)

characteristics of connective tissue

extracellular matrix

nonliving material that surrounds living cells

ground substance and fibers

2 main elements of the extracellular matrix

ground substance

mostly water, along with adhesion protins and polysaccharide molecules

fibers

collagen (white) fibers, elastic (yellow) fibers, reticular fibers (a type of collagen)

bone (osseous tissue), cartilage, dense connective tissue, loose connective tissue, blood

types of connective tissue from most rigid to softest, or most fluid

bone (osseous tissue)

composed of osteocytes, hard matrix of calcium salts, large number of collagen fibers, and functions to protect and support the body

osteocytes

bone cells sitting in lacunae (cavities)

chondrocyte

cartilage cell

cartilage

less hard and more flexible than bone, found in only a few places in the body, chondrocyte is the major cell type TYPES: 8 cartilage: most WIDESPREAD type of cartilage, abundant collagen fibers hidden by a glassy, rubbery matrix LOCATION: trachea, attaches ribs to the breastbone, covers ends of long bones, entire fetal skeleton prior to birth; epiphyseal (growth) plates in long bones elastic cartilage: produces elasticity LOCATION: supports the external ear fibrocartilage: highly compressible LOCATION: forms cushion-like between vertebrae of the spinal column

dense connective tissue

dense fibrous tissue

dense fibrous tissue

main matrix element is collagen fiber, fibroblasts are cells that make fibers LOCATIONS: tendons, ligaments, dermis

tendons

attach skeletal muscles to bone

ligaments

attach bone to bone at joints and are more elastic than tendons

dermis

lower lays of the skin

loose connective tissue

softer, have more cells and fewer fibers than other connective tissues (except blood)

areolar, adipose, and reticular

types of loose connective tissues

areolar

most WIDELY DISTRIBUTED CONNECTIVE TISSUE, soft pliable tissue like 'cobwebs', functions as a universal packing tissue and 'glue' to hold organs in place

adipose (fat)

FUNCTIONS: insulates the body, protects some organs, serves as a site of fuel storage LOCATIONS: subcutaneous tissue beneath the skin, fat 'depots' include hips, breasts, and belly

reticular

delicate network of interwoven fibers with reticular cells (like fibroblasts), form stroma (internal framework) of organs LOCATIONS: lymph nodes, spleen, bone marrow

blood (vascular tissue)

blood cells surrounded by fluid matrix known as blood plasma, soluble fibers are visible only during clotting,functions as the transport vehicle for the cardiovascular system (nutrients, wastes, respiratory gases)

muscle tissue

function is to contract, or shorten, to produce movement

skeletal muscle, cardiac muscle, and smooth (visceral) muscle

three types of muscle tissues

skeletal muscle

voluntary controlled CHARACTERISTICS: striations (stripes), multinucleate (more than one nucleus), long, cylindrical shape

cardiac muscle

involuntary controlled, found only in the heart CHARACTERISTICS: striations, one nucleus per cell, short, branching cells

intercalated discs

containing gap junctions to connect cells

smooth (visceral) muscle

found in walls of hollow organs such as stomach, uterus, and blood vessels; peristalsis, a wavelike activity, is a typical activity CHARACTERISTICS: no visible striations, one nucleus per cell, spindle-shaped cells

nervous tissue

function is to receive and conduct electrochemical signals to and from body parts (irritability and conductivity), composed of neurons and nerve support cells

regeneration and fibrosis

two ways of tissue repair

regeneration

replacement of destroyed tissue by the same kind of cells

fibrosis

repair by dense (fibrous connective tissue, scar tissue)

clean cuts (incisions)

these heal more successfully than ragged tears of the tissue

epithelial tissue (skins and mucous membranes), fibrous connective tissues and bone

tissues that regenerate easily

skeletal muscle

tissues that regenerate poorly

cardiac muscle, nervous tissue within the brain and spinal cord

tissues that are replaced largely with scar tissue

fibrocartilage

cartilage type with a great deal of collagen in the matrix

adipose

tissue type that is actually modified areolar tissue

adipose

tissue type that stores lipid molecules

tissue type composed of Haversian systems

compact bone

hyaline cartilage

most common type of cartilage

dense fibrous connective tissue

strong tissue that forms tendons and ligaments

cancellous bone

tissue type associated with red bone marrow

dense fibrous connective tissue

tissue type that forms strong membranes

fibrocartilage

connective tissue that forms the disks between vertebrae

cancellous bone

tissue type that forms hard mineral trabeculae

goblet cell

a type of cell found in simple columnar and pseudostratified tissue that secretes mucus

exocrine glands

one of two kinds of glands, it secretes substances onto epithelial surfaces

cilia

a cellular organelle, it is a projection that moves substances along the surfaces

transitional epithelium

a type of epithelial tissue especially welly adapted to excessive stretching

mucous

mucous membranes secrete this water-based protein solution

keratin

a tough, waterproof material found in the upper layers of some examples of stratified squamous epithelium

simple cuboidal

the type of epithelial tissue likely to be found forming glands

keratinized stratified squamous

the type of epithelial tissue likely to be found on the palm of the hand

skeletal and smooth

voluntary type of muscle tissue

cardiac

an involuntary type of muscle tissue is

cardiac

which of these muscle tissues is striated?

smooth

which of these is most likely to be found in the wall of the urinary tract?

intercalated disks

cardiac muscle fibers are connected end-to-end by means of

skeletal muscle

which of these cells is likely to have multiple nuclei?

neurons

nerve tissuecontains cells called...

brain and vertebrae

nerve tissue forms the bulk of the...