Chapter 4: the tissue level of organization

why are infections always a serious threat after a severe burn or an abrasion?

The extensive connections between cells formed by tight junctions, intercellular cement, and physical interlocking hold skin cells together and can deny access to chemicals or pathogens that may cover their free surfaces. If the skin is damaged the connections are broken, infections can easily occur.

The lining of the nasal cavity is normally moist, contains numerous goblet cells, and a rests on a layer of loose connective tissue. What type of membrane is this?

The lining of the nasal cavity is a mucous membrane

What physiological function are enhanced by epithelial cells bearing microvilli and Celia

The presence of microvilli on the free surface of epithelial cells greatly increases the surface area of absorption. Cilia function to move materials over the surface of epithelial cells.

Secretory cells of sebaceous glands associated with hair follicles fill with secretions and then rupture, releasing their contents. What kind of secretion is this?

The process described is holocrine secretion

secretory cells of sebaceous glands associated with hair follicles fill with secretions and then ruptured, releasing their contents. What kind of secretion is this?

The process described is holocrine secretion

Chemical analysis of a connective tissue reveals that the tissue contains primarily triglycerides. which type of connective tissue is this?

The tissue is adipose (fat) tissue

Which two types of connective tissue have a fluid matrix?

The two connective tissue that contain a fluid matrix our blood and lymph

a significant structural feature in the digestive system is the presence of tight junctions located near the exposed surface of cells lining the digestive tract. Why are these junctions so important?

Tight junctions block the passage of water up or solute between cells. in the digestive track, these junction keep enzymes, acids, and wastes from damaging delicate underlying tissues.

peri-

around; pericardium

inter-

between; interstitial

soma

body; desmosome

os

bone; osseous tissue

Why does cartilage heal so slowly?

cartilage lacks a direct blood supply, which is necessary for rapid healing to occur. Materials that are needed to repair damaged cartilage must diffuse from the blood to the chondrocytes. Such diffusion takes a long time and retards the healing process.

chondros

cartilage; perichondrium

How does a cell membrane differ from a tissue-level membrane?

cell membranes are composed of lipid bilayers. Tissue membranes consist of a layer of epithelial tissue and a layer of connective tissue.

Lack of vitamin C in the diet interferes with the ability of fibroblasts to produce collagen. What effect might this interference have on connective tissue?

collagen fibers add string to connected tissue. Thus, a vitamin C deficiency might result in connective tissue that is weak and prone to damage.

The tissue that contains the fluid ground substance is

connective

Epithelial tissue is composed of layers of cells that

cover internal or external surfaces

what characteristics make the cutaneous membrane different from the serous and mucous membranes?

cutaneous membranes are thick, relatively waterproof, and usually dry

Through process of differentiation

each cell specializes to perform a relatively restricted range of functions

Hormones

endocrine secretion

holos

entire; holocrine

gland cells

epithelial cells that produce secretions

The four basic tissue types found in the body are

epithelial, connective, muscle, neural

pseudes

false; pseudostratified

Adipocytes

fat cells

Which fluid connective tissues and supporting connected tissues are found in the human body?

fluid connective tissues: blood and lymph Supporting connective tissues:bone and cartilage

What three types of layering make epithelial tissue recognizable?

simple, stratified, transitional

A biology student loses the labels of two prepared slides she is studying. One is a slide of animal intestine, and the other is of animal esophagus. You volunteered to help her sort them out. How would you decide which slide is which?

since animal intestines are specialized for absorption, you would look for a slide that shows a single layer of epithelium lining the cavity. The cells would be cuboidal or columnar and would probably have microvilli on the surface to increase surface area. With the right type of microscope, you could also see tight junctions between the cells. Since the esophagus received undigested food, it would have a stratified epithelium consisting of squamous cells to protect it against damage.

Large muscle fibers that are multinucleated, striated, and voluntary are found in

skeletal muscle tissue

What three basic components are found in connective tissues?

specialized cells, extracellular protein fibers, fluid ground substance

mucus secretion that coats the passageways of the digestive and respiratory tract result from _______________ secretion.

merocrine

meros

part; merocrine

squama

plate or scale; squamous

lacus

pool; lacunae

What are the four essential functions of epithelial tissue?

provide physical protection; control permeability; provide sensation; produce specialized secretions

The primary function (s) of epithelial tissue is (are)

providing physical protection, controlling permeability and providing sensation, producing specialized secretions

The type of epithelium that typically possesses cilia and lines the nasal cavity, trachea, and bronchi is

pseudo stratified columnar epithelium

Muscle- two-bone attachment

tendon

neuron

A cell in neural tissue specialized for intercellular communication by (1) changes in membrane potential and (2) synaptic connections

Tissue

A collection of specialized cells and cell products that perform a specific function

Cartilage

A connective tissue with gelatinous matrix containing an abundance of fibers

Basement membrane

A layer of filaments and fibers attached an epithelium to the underlying connective tissue

Microvilli

Absorption and secretion

why are both skeletal muscle cells and axon also called fibers?

Both skeletal muscle cells and neurons are called fibers because they are relatively long and slender

Fibroblasts

Cells of connective tissue proper that are responsible for the production of extracellular fibers and the secretion of the organic compounds of the extracellular matrix

gap junction

Connections between cells that permits the movement of ions and the transfer of graded or propagated change in the membrane potential from cell to cell

blood

Connective tissue that contain distinctive collections of cells in the fluid matrix

The three cell shapes making of epithelial tissue are

Cubital, squamous, columnar

what is the difference between an exocrine secretion and a endocrine secretion?

Exocrine secretions are secreted onto a surface or outward through a duct. Endocrine secretions are secreted by a ductless glands into surrounding tissues. The secretions are called hormones which usually diffuse into the blood for distribution to other parts of the body.

lymph

Fluid contents of lymphatic vessels, similar in composition to interstitial fluid

what type of muscle tissue has small, spindle-shaped cells with single nuclei and no obvious banding pattern?

Given that both cardiac and skeletal muscles are strained (banded), this must be smooth muscle tissue.

gap junction

Interlocking of membrane proteins

Simple cuboidal epithelium cells are specialized to

Secrete enzymes and buffers in the pancreas and salivary glands

mucous membrane

Lines cavities that communicate with the exterior. Their services are normally moisten by mucus secretions.

intercalated discs and peacemaker cells are a characteristic of

Muscle tissue

The types of layering used to classify epithelia are

Simple and Stratified

neural tissue

Specialized to conduct electrical impulses that convey information from one area of the body to another

Histology

Study of tissues

Connective tissue

One of the four primary tissue types; provides a structural framework for the body that stabilizes the relative position of the other tissue types: includes connective tissue proper, cartridges, bone, and blood; always has cells, cell products, and grounds substances.

Voluntary control is restricted to which type of muscle tissue?

Only skeletal muscle tissue is voluntary

What indications are associated with inflammation?

Redness, warmth, swelling, and pain are familiar indications of inflammation

Germinative cells

Repair and renewal

Inflammation

a nonspecific defense mechanism that operates at the tissue level, characterized by swelling, redness, warmth, and pain

microphage

a phagocytic cell of the monocyte - microphage system

muscle tissue

a tissue characterized by the presence of cells capable of contraction; include skeletal cardiac, and smooth muscle tissue

apo-

from; apocrine

Stem cells

germinative cells, continually replace the short-lived epithelial cells

hyalos

glass; hyaline cartilage

glia

glue, neuroglia

cardium

heart; pericardium

destroys gland cell

holocrine secretion

Why does holocrine secretion require continuous cell division?

holocrine secretion destroys the gland cell. during holocrine secretion the entire cell becomes packed with secretory products and the bursts, releasing the secretion by killing the cell. The gland cells must be replaced by the division of stem cells.

Cardiac muscle

intercalated discs

tight Junction

intercellular connection

What is fibrosis?

is the permanent replacement of normal tissue by fibrous tissue

Bone-to- bone attachment

ligament

desmos

ligament; desmosome

serous membrane

line internal cavities and are delicate, moist, and very permeable

Which four kinds of membranes composed of epithelial and connective tissues cover and protect other structures and tissues in the body?

mucous, serous, cutaneous, synovial

neuro

nerve, neuron

You look at a tissue under a light microscope and see a simple squamous epithelium on the outer surface. Can it be a sample of the skin surface?

no. A simple squamous epithelium is not found in the skin surface because it cannot provide enough protection against infection, abrasion, and dehydration.

Epithelium

one of the four primary tissue types; a layer of cells that form is superficial covering or an internal lining of a body cavity or vessel

bone

osseous tissue, has a matrix primarily consisting of collagen fibers and calcium salts, which gives unique properties

pleura

rib; pleural membrane

serous membranes produce fluids. What is their function?

serous fluid minimizes the friction between the serous membrane that cover the surfaces of organs in the surrounding body cavity

The type of epithelial cells found in protected regions where absorption takes place or a slippery surface reduces friction is

simple squamous

You are asked to develop a scheme that can be used to identify the three different types of muscle tissue in two steps. What were the two steps be?

step one: check for striations. (If striations are present, the choices are skeletal muscle or cardiac muscle. If striations are absent the tissue is smooth muscle.) step two: check for the presence of intercalated discs. (if the discs are present, the tissue is cardiac muscle. If they are absent, the tissue is skeletal muscle.)

In body surfaces where mechanical stresses are severe, the dominant epithelium is

stratified squamous epithelium

Skeletal muscle

striated and voluntary

histos

tissue; histology

Collections of specialized cells and cell products that perform a limited range of functions are called

tissues

phagein

to eat; macrophage

The primary function of serous membranes in the body

to minimize friction between opposing surfaces

krinein

to secrete; exocrine

sistere

to set; interstitial

dendron

tree; dendrites

vas

vessel, vascular

a-

without; avascular