Chapter 5: Study Guide

What is the function of adipose tissue and where is it found?

- (areolar tissue with predominantly adipocytes) - beneath skin, between muscles, behind eyes, around heart and joints, bone marrow, abdomen - functions: energy store, thermal insulation, shock absorber

What are desmosomes and what cytoskeletal protein are they made of?

- a strong welded plaque (thickening) connecting plasma membranes of adjacent cells - made of intermediate filaments (tonofilaments)

What are fat cells called and where are they most commonly found in the body?

- adipocytes - adipose tissue: beneath skin, between muscles, surrounding joints, in bone marrow

Why is cartilage slow to heal, and how does it get nutrients?

- avascular - receives nutrients from the perichondrium (surrounding membrane)

Is epithelial tissue vascular or avascular? How does epithelial tissue get its nutrients?

- avascular - underlying connective tissue provides nutrients and oxygen

What is the name of the layer underneath the epithelium, and what is it made of?

- basement membrane / basal lamina - made of nonliving network of fibers - partial barrier between epithelial tissue and underlying connective tissue - nutrients and oxygen diffuse through the basement membrane from underlying tissue into epithelial tissue - strong, elastic, prevents cells from being torn off

Name places that have keratinized stratified squamous tissue versus non-keratinized stratified squamous. What is the difference?

- because keratin is tough and fibrous, it helps protect underlying tissue from heat, pathogens, and chemicals - found on skin surface (epidermis) - non-keratinized stratified squamous have cells that secrete mucus to prevent desiccation and lubricate against friction - found in mouth, vagina, esophagus Difference: keratinized: as cells move up, keratin increases and cells die as they move away from nutrient supplies non-keratinized: cells do not have a lot of keratin and are kept moist by mucus

What is the major function and location of elastic connective tissue?

- between vertebrae, artery walls and other areas that stretch (stomach, bronchi, bladder - provides stretchiness, flexibility and support

What is the suffix for immature cells? For mature cells? Immature cartilage cells are called ______________. Immature bone cells are called ______________. Mature cartilage cells are called _____________. Mature bone cells are called ______________.

- blast - cyte Immature cartilage cells are called chondroblasts. Immature bone cells are called osteoblasts. Mature cartilage cells are called chondrocytes. Mature bone cells are called osteocytes.

What are mature cartilage cells called and where are they found?

- chondrocytes, found in lacunae (hollow pockets of the matrix)

What is the hair-like covering of some epithelial cells? Name a place they are found in the body, and why.

- cilia - trachea: moves mucus away from lungs towards the mouth to get rid of debris and trapped pathogens

What fiber of extracellular matrix is thickest and strongest? In what tissues is it most common?

- collagenous fibers - tendons, ligaments (dense connective)

Where do epithelial cells connect with each other, and what is this called?

- connect at junctional complexes, with very little space for matrix in between (if at all)

What is the most abundant tissue in the body by weight? What is it mostly composed of rather than living cells?

- connective tissue - mostly composed of nonliving extracellular matrix

What gap junction contains transmembrane proteins?

- connexons: tubular channel proteins - extends from cytoplasm of one cell to cytoplasm of another - allow exchange of ions and nutrients

Explain where the following epithelial types are found in the body and why this makes sense based on their number and shape: stratified columnar

- deeper layers can be cuboidal or columnar - like other stratified epithelium, apical layers slough off and can be replaced by lower layers, allowing them to be replaced and repaired when damaged - protect underlying tissues - found in a few parts of respiratory/digestive/reproductive system and excretory ducts - like simple columnar, large number of organelles for higher levels of absorption and secretion than cuboidal and has more protection than cuboidal

Which connective tissues have a low level of blood vessels, and how does this affect them?

- dense connective tissue (low), cartilage (avascular) - this means these tissues are slow to heal (tendons and ligaments are dense connective)

What is the major function and location of dense irregular connective tissue?

- dermis, fibrous covering of some organs (kidneys, liver), tough capsules of joints - functions to withstand stress from multiple directions, functions to connect and support structures

What are the most stretchy fibers? Where are they found?

- elastic fibers made of mostly elastin - vocal cords, lungs, skin, blood vessel walls

Why does parvovirus affect epithelial cells in the animal more than other cells? What are some symptoms?

- feline panleukopenia - canine parvoviral enteritis - parvovirus target and kills mitotic cells, such as in epithelial tissue that continually renews itself - parvo causes epithelial tissues to die and slough off, such as in the intestinal tract, and nutrients cannot be absorbed - hemorrhagic diarrhea, vomiting, dehydration

Why are cardiac and smooth muscle cells joined by a gap junction?

- for quick transport of electrical signals to coordinate contraction

Explain where the following epithelial types are found in the body and why this makes sense based on their number and shape: stratified squamous

- found in skin - cells move up through layers and become keratinized, created a tough waterproof layer protecting underlying tissues from heat/pathogens/chemicals/desication/abrasion - constantly sheds to heal/protect from damage - flatness: many layers - found in places of abrasion: mouth, vagina, esophagus

Where in the body does epithelial tissue have desmosomes, and why is this necessary?

- found in tissues that are subjecting to tension and stretching - heart, uterus, skin - prevents tears

What are tight junctions, where are they found in the body, and why is this necessary?

- fusion of plasma membrane of neighboring cells, with no matrix in between the cells - transport can only happen through cell cytoplasm - these junctions exist where there can be no leaks afforded: urinary bladder, digestive tract (to prevent leakage of digestive enzymes)

What two chemicals do the dark granules of mast cells release? What are their functions?

- histamine: makes capillaries leaky and increases blood flow - heparin: prevents blood from clotting, keeps pathways open for increased blood flow

- What glycoprotein molecule found in ground substance holds cells together to protect from invasion? - What enzyme do some bacteria make that can erode this molecule and spread into tissues? Conversely, why do WBCs produce it?

- hyaluronic acid - bacterial enzyme: hyaluronidase - WBCs: liquifies matrix and allows WBCs to pass through loose connective tissue easier

Explain where the following epithelial types are found in the body and why this makes sense based on their number and shape: simple columnar

- large number of organelles for higher levels of absorption and secretion than cuboidal, single layer for efficient transport - e.g. goblet cells secrete mucous > found along GI tract, excretory ducts > ciliated are found in uterine tubes, respiratory tract - thicker and more protective than cuboidal > impermeable against ingested bacteria in stomach and digestive tract lining

What are white blood cells called and what is the process called when they squeeze out of the bloodstream and into tissues?

- leukocytes - diapedesis

Explain where the following epithelial types are found in the body and why this makes sense based on their number and shape: simple squamous

- lining of surfaces for passage of gas of liquid, single layer for efficient transport > delicate, thin: easy passage/exchange of molecules - kidney filtration membranes, lung alveoli > smooth, flat: reduces friction - lining of blood and lymphatic vessels

What are the names given to macrophages in these different tissues: - liver - brain - loose connective tissue - lung (why)

- liver: Kupffer cells - brain: microglial cells - loose connective tissue: histiocytes - lung (why): clears debris such as dust from alveoli

Explain where the following epithelial types are found in the body and why this makes sense based on their number and shape: simple cuboidal

- locations of secretion, absorption, single layer for efficient transport > secretory portions of glands (e.g. thyroid), lining ducts (liver, pancreas, kidney, salivary glands) > thickness allows space in cytoplasm for mitochondria and other organelles for efficient and high levels of active transport - locations of protection: thicker than squamous, tightly packed with little intracellular space between cells > ovarian surface, ducts of respiratory tracts

Which connective tissues have a high level of blood vessels?

- loose connective tissue and adipose tissue

What are the finger-like projections covering some epithelial cells? Where can they be found? What is their function?

- microvilli - makes the cell's brush border - increases surface area, increasing absorptive ability, so they usually occur in areas of secretion and absorption - intestinal and urinary tracts

What is the function of areolar tissue and where is it found?

- most common, found everywhere, predominant cell is fibroblasts - surrounds every organ, in every mucus membrane - functions to support and cushion body structures and provide nutrients

Explain where the following epithelial types are found in the body and why this makes sense based on their number and shape: stratified cuboidal

- mostly found in 2 layers in large excretory ducts (sweat glands, mammary glands, salivary glands) - multiple layers mean outer layer can slough off when tight junctions break down, and are replaced by lower layers - like simple cuboidal, thickness allows space in cytoplasm for mitochondria and other organelles for efficient and high levels of active transport

What do goblet cells secrete, and what type of cell are they (shape, layers)?

- mucous - simple columnar epithelial

- what epithelia has one layer of cells - what epithelia has multiple layers of cells - what are flat, square, and rectangular cells called

- one layer = simple - multilayered = stratified - flat: squamous - square: cuboidal - rectangular: columnar

What is the function of reticular tissue and where is it found?

- provides framework for liver, spleen, lymph nodes, bone marrow

What fibers are net-like and are found in which tissues?

- reticular fibers made of collagen - support highly cellular organs: lymph nodes, endocrine glands, spleen, bone marrow, liver - around capillaries, nerves, muscle fibers, blood vessels

Explain where the following epithelial types are found in the body and why this makes sense based on their number and shape: transitional

- shape of cells changes depending on function of organ: basal = cuboidal or columnar, superficial = squamous - leak proof, allows contraction and expansion: ureters, urethra, bladder - thicker basal layer has many mitochondria for energy to renew the epithelium, middle layer is rapidly dividing to provide new apical layer as it is injured and sloughs off

Explain where the following epithelial types are found in the body and why this makes sense based on their number and shape: pseudostratified columnar

- single layer, nuclei appear at different levels in the cell - not all cells reach the apical surface of the tissue - cell volume allows for a large number of organelles for high level of secretion and absorption; have goblet cells interspersed; thickness allows for protection - ciliated cells found in fallopian tube to move the ovum, respiratory tract - non-ciliated found in male reproductive system - has supportive cells and bipolar receptor cells

What is the major function and location of dense regular connective tissue?

- tendons, ligaments, aponeurosis - has high tensile strength, functions to connect structures in the body

Why are epithelial cells bipolar?

- they have two distinct sides: - apical surface faces the lumen of organ or body cavity - basal surface faces underlying connective tissue

What are the 3 types of specialized connective tissue?

1. cartilage 2. bone 3. blood

What are the 3 types of dense connective tissues

1. dense regular 2. dense irregular 3. elastic

What are the 3 distinct components of connective tissues?

1. ground substance (part of extracellular matrix) 2. extracellular fibers (part of extracellular matrix) 3. cells

Where are the 3 different types of cartilage found?

1. hyaline: most common - articular cartilage, connects ribs and sternum, tracheal rings, embryonic skeleton, growth plates 2. elastic: epiglottis, pinnae 3. fibrocartilage: between vertebrae of spine, between bones in pelvic girdle, knee joint

Why does normal compression of joints cause no pain?

Cartilage surrounding joints has no nerves

Give examples in the body of all of the following functions of epithelial tissue: Protection Filters Absorption Sensory input Secretion Excretion

Protection: skin: protects underlying tissues with layers of keratinized cells from physical injury, pathogens, and drying out; epithelial tissue protects internal organs from stomach acid Filters: epithelial tissue in kidney filters out molecules/nutrients/waste from blood Absorption: epithelial tissue lining the intestines absorbs nutrients from food Sensory input: epithelial tissue of the skin has specialized nerve ending (Meissner's and Pacinian corpuscles) that sense touch, pressure, and vibration Secretion: epithelial tissue lining the respiratory tract secretes mucus to trap debris and pathogens Excretion: epithelial tissue of sweat glands excrete sweat, epithelial tissue of kidneys excrete waste filtered from blood

What do fibroblasts do?

Secrete fibers and ground substance that makes up the extracellular matrix

What are the 3 types of loose connective tissues?

areolar, adipose, reticular

What part of the neuron carries signals to other cells?

axon

What part of the neuron brings information into the cell?

dendrites

What are glands that secrete hormones directly into the bloodstream and do not have ducts? Give examples.

endocrine glands - secrete hormones into lymphatic system or bloodstream to be carried throughout body - part of the endocrine system ex: pituitary gland, adrenal gland

What are glands that have a duct or tube for their secretions? Give examples.

exocrine glands - secrete from ducts directly into surrounding area ex: sweat and salivary glands, liver (bile), pancreas (digestive enzymes)

What is the name of the fluid in blood? What 3 major cell types are found in it?

fluid = plasma cells = erythrocytes, leukocytes, thrombocytes

What is ground substance mostly made of?

glycoproteins

What is another name for cartilage, used in parts of meat that are difficult to chew

gristle

Give examples of why you would need to know gross anatomy and histology.

gross: organ systems, organ/system disorders, health - physical exams, normal anatomy & physiology to know when something is wrong or normal histology: diagnosing (blood smears, fecals, biopsy, urinalysis), understanding the basis of how tissues and organs function

What is the waterproofing protein made by skin epithelia?

keratin

What do goblet cells secrete?

lubricating mucus

Reticular cells are mostly found in the immune system in what organs?

lymph nodes, spleen, bone marrow

What internal organelle of macrophages break up the bacteria/dead cells/debris that is phagocytized?

lysosomes

What cells help support neurons?

neuroglial cells

What is another name for bone tissue?

osseous connective tissue

What is the cell body of a nerve called?

perikaryon

What part of the neuron decides whether or not to fire?

perikaryon

Is connective tissue vascular or avascular?

vascular

What is the difference between white and brown fat? Which animals have brown fat and why?

white: - lipid stored in a single large droplet with other organelles and cytoplasm pushed to the edges - found throughout body and especially in deep layers brown: - cytoplasm clearly visible and lipids are stored in multiple small vesicles - energy is released as heat, important role in temperature regulation - has high number of mitochondria - found in newborn animals and hibernating animals