Unit 2 / Chapter 4 / Histology

Question 1

The study of the normal structure of tissues.

Answer 1

Histology

Question 2

What is the MAJOR tissue type?

Coverings and linings, skin, sheets of cells on top of basement membrane, edges face air or fluid

Answer 2

Epithelium

Question 3

What is the MAJOR tissue type?

Holds tissues together, bind, support, protect, allows transport, fibers, goo

Answer 3

Connective

Question 4

What is the MAJOR tissue type?

Movement, contracts to generate force, skeletal, cardiac, smooth

Answer 4

Muscular

Question 5

What is the MAJOR tissue type?

Information, communication, conduction of electrical impulses, also cells which support the information cells’ function

Answer 5

Nervous

Question 6

Type of junction:
Impermeable; no passage of macromolecules between cells.
Ex: BBB - blood brain barrier

Answer 6

Tight Junction

Question 7

Type of junction:

Resist mechanical stress, but ECM molecules can pass between cells. Ex: skin cells in epidermis

Answer 7

Desmosomes

Question 8

Type of junction:
Small pores in protein channels. Allows free passage of small substances between the cytosol of 2 cells.
Ex: cardiac muscle

Answer 8

Gap Junction

Question 9

Epithelium type:
Function: Absorption, secretion, filtration (gas exchange), production of fluid in serous membranes
Location: air sacs of lungs, serous membranes, kidney glomeruli, endothelial lining of vessels.

Answer 9

Simple Squamous Epithelium

Question 10

Epithelium type:

Flat cells with central nucleus, 1 layer

Answer 10

Simple Squamous Epithelium

Question 11

Epithelium type:
Function: secretion and absorption
Location: kidney tubules, ducts of glands, thyroid, respiratory

Answer 11

Simple Cuboidal Epithelium

Question 12

Epithelium type:

1 layer, cells are as tall as wide, square appearing with large central nucleus

Answer 12

Simple Cuboidal Epithelium

Question 13

Epithelium type:
Function: absorption, secretion, also propulsion where ciliated
Location: stomach, small intestine, colon, gallbladder, kidney tubules, uterine tube
Specialized features: microvilli, cilia, goblet cells

Answer 13

Simple Columnar Epithelium

Question 14

Epithelium type:

1 layer, cells taller than wide, nuclei toward base

Answer 14

Simple Columnar Epithelium

Question 15

Epithelium type:
Function: protection from mechanical stress, microbes, (skin: also dehydration)
Location: skin (keratinized);
mouth, throat, esophagus, anus, vagina (nonkeratinized)

Answer 15

Stratified Squamous Epithelium

Question 16

Epithelium type:

More than 1 layer, flat, stacked cells, round w/ nuclei near basement membrane, flatter near surface

Answer 16

Stratified Squamous Epithelium

Question 17

Epithelium type:
Function: cilia for propulsion, secretion, goblet cells produce mucus
Location: respiratory tract: nasal, tracheal; also portion of male urethra

Answer 17

Pseudostratified Ciliated Columnar Epithelium (PCCE)

Question 18

Epithelium type:

1 layer, looks like more, closely packed columnar cells, nuclei at different heights, goblet cells

Answer 18

Pseudostratified Ciliated Columnar Epithelium (PCCE)

Question 19

Epithelium type:
Function: stretch/distensibility - cells look more flat when structure that they line is distended.
Location: urinary tract from renal pelvis, ureter, bladder, urethra

Answer 19

Transitional Epithelium

Question 20

Epithelium type:

squamous-to-cuboidal (multiple cell layers, so stratified)

Answer 20

Transitional Epithelium

Question 21

Structures which forms and secretes a product.

Answer 21

Glands

Question 22

Structure that secretes products to the bloodstream.

Answer 22

Endocrine Glands

Question 23

Structure that releases products to epithelial surface or into ducts.

Answer 23

Exocrine Glands

Question 24

Exocrine Gland:

Unicellular and releases mucus to digestive and respiratory tracts.

Answer 24

Goblet Cell

Question 25

Exocrine Gland: Multicellular, most glands, including salivary and sweat, cell products in secretory vesicles, cell survives, water, salty

Answer 25

Merocrine Gland

Question 26

Exocrine Gland: Multicellular, sebaceous glands, products releases into cytosol, cell dies to release product, mitosis to replace dying cells

Answer 26

Holocrine Gland

Question 27

Cells of connective tissue proper: | Produce the protein fibers and extracellular matrix

Answer 27

Fibroblasts

Question 28

Cells of connective tissue proper: | Fat cells

Answer 28

Adipocytes

Question 29

Cells of connective tissue proper: | Immune response, produce inflammatory mediators such as histamine

Answer 29

Mast Cells

Question 30

Cells of connective tissue proper: | Consume dead and tying tissue

Answer 30

Phagocytes

Question 31

Connective tissue proper type: - appearance: Webs of fibers - location(s): Underneath epithelium, serosa, walls of hollow organs - special functions: support of blood vessels, diffusion to epithelium - specialized cells: fibroblasts dominate; lots of immune cells

Answer 31

Loose Fibrous (Areolar) Connective Tissue

Question 32

Connective tissue proper type: - appearance: orderly packed, nearly parallel fibers - location(s): tendons and ligaments - special functions: distributes tension in one direction - specialized cells: fibroblasts

Answer 32

Dense Fibrous Regular Connective Tissue

Question 33

Connective tissue proper type: - appearance: swirly clustered bundles of fibers - location(s): dermis; capsules of joints and organs - special functions: distributes tension in all 3 planes - specialized cells: fibroblasts

Answer 33

Dense Fibrous Irregular Connective Tissue

Question 34

Connective tissue proper type: - appearance: Wavy purple staining fibers (elastin) + random collagen - location(s): large blood vessels, some ligaments - special functions: stretch - specialized cells:

Answer 34

Elastic Connective Tissue

Question 35

Connective tissue proper type: - appearance: Dark vines (type III collagen) - location(s): lymph nodes, spleen bone marrow, liver, basement membranes - special functions: provides structure inside organs

Answer 35

Reticular Connective Tissue

Question 36

Connective tissue proper type: -appearance: “marshmallows” Nucleus is pushed off to side. Large vacuole on slide is empty; held triglycerides -location(s): deep to skin in the abdomen, thighs, buttocks, hips, breasts; also visceral Note: the “brown fat” seen in children contains abundant mitochondria -special functions: insulation, warmth, shock absorption, protection, energy reserve -specialized cells: adipocyte

Answer 36

Adipose Connective Tissue

Question 37

Specialized connective tissue type: -appearance: glasslike matrix. The cells are often seen in pairs, look like “owl eyes.” -location(s): articular surfaces, rib attachments, nose, respiratory tubes -special functions: shock absorption -specialized cells: chondrocytes ++Note that cartilage is avascular, and gets its blood supply from the perichondrium, at the edge of the tissue.

Answer 37

``` Hyaline Cartilage (simplest case for cartilage) ```

Question 38

Specialized connective tissue type: - appearance: slender purplish staining elastic fibers + glassy matrix and chondrocytes - location(s): External ear and epiglottis/portions of larynx - special functions: flexibility, can vibrate - specialized cells: chondrocytes

Answer 38

Elastic Cartilage | hyaline cartilage + elastic fibers

Question 39

Specialized connective tissue type: - appearance: stringy fibers + glassy matrix and chondrocytes - location(s): fibrous joints - pubic symphysis, intervertebral discs, articular discs (menisci, TFC of wrist) - special functions: tensile strength and elasticity - specialized cells: chondrocytes and fibroblasts

Answer 39

Fibrocartilage | hyaline cartilage + collagen fibers

Question 40

Specialized connective tissue type: -appearance: “tree ring” or “onion slice” appearance of compact bone -location(s): skeleton -special functions: support, protection onf vital organs, muscle attachment sites, calcium storage, hematopoietic marrow -specialized cells: Osteoblasts: bone building cells at the edges Osteocytes: mature osteoblasts now trapped in the rings of bone matrix Osteoclasts: resorb and destroy at the edges

Answer 40

Bone

Question 41

Specialized connective tissue type: - appearance: suspension of about 45% cells, 99% of which are red blood cells. Plasma is the extracellular fluid here, water with dissolved salts and proteins. - location(s): inside vessels - special functions: O2/CO2 exchange, waste removal, also immunity, clotting - specialized cells: erythrocytes, white blood cells and platelets.

Answer 41

Blood

Question 42

Muscular Tissue: - appearance: striated, parallel fibers. Eccentric nuclei. - location(s): skeleton (trunk, limbs, face) - special functions: voluntary control - specialized cells: myocyte

Answer 42

Skeletal Muscle

Question 43

Muscular Tissue: -appearance: striated, branched; shorter and thicker than skeletal muscle. 1-2 nuclei per cell, eccentric -location(s): heart only -special functions: involuntary; electrical/contractile -feature: intercalated discs (desmosome + modified tight junction)

Answer 43

Cardiac Muscle

Question 44

Muscular Tissue: -appearance: smooth spindle shaped cells with central nuclei (long tapered cells) -location(s): walls of hollow organs, blood vessels; certain structures in the eye, also in skin and ducts of some glands. -special functions: involuntary -specialized cells: gap junctions in plasma membrane

Answer 44

Smooth Muscle

Question 45

Identify where in the body nervous tissue can be found

Answer 45

Central nervous system: brain and spinal cord Peripheral nervous system: cranial and spinal nerves.

Question 46

What is a neuron?

Answer 46

Neurons: the information cell; the “gray matter” of the brain and spinal cord.

Question 47

What are the structural characteristics of a Neuron and the function of these structures?

Answer 47

Cell body (soma) – mature cells. Amitotic. Conducts nerve impulses. Processes: multiple dendrites (incoming), single axon (outbound) Appearance: Polygonal in shape, single central nucleus, several processes

Question 48

What are the functions of Neuroglial cells?

Answer 48

Neuroglial cells: Functions to support the neuron, don’t carry information. These do undergo mitosis Functions include: anchoring neurons and vessels in place, making and circulating cerebrospinal fluid (CSF), insulation of axons, immune surveillance

Question 49

Thin sheet of 1 or more tissues lining a body surface or cavity is a ____________________.

Answer 49

Membrane | which is an organ

Question 50

“True” membranes: Line pleural, peritoneal, pericardial cavities Simple squamous epithelium (mesothelium) + basement membrane + loose CT Produces serous fluid (thin, lubricating) Visceral portion covers organ, parietal portion lines the space.

Answer 50

Serous Membrane

Question 51

"True" membranes: Lines cavity of synovial joints 2 layers of modified fibroblasts (synoviocytes) + loose connective tissue Outside is dense irregular CT, the joint capsule.

Answer 51

Synovial Membrane

Question 52

“Membrane-like structures”: All body passages open to the outside (respiratory, digestive, urogenital) Epithelia + basement membrane, with loose CT underneath. Contains mucus secreting glands.

Answer 52

Mucous Membrane

Question 53

"Membrane-like structures": Skin Epidermis is avascular: keratinized stratified squamous epithelium Dermis: papillary (upper) portion is loose CT; reticular (lower) portion is dense irregular CT

Answer 53

Cutaneous Membrane

Question 54

How does Epithelium tissue generally repair?

Answer 54

typically regenerates

Question 55

How does Connective tissue generally repair?

Answer 55

CT proper, bone and blood: regenerate | Cartilage: fibrosis (chondrocytes with limited capacity to divide). * blood supply

Question 56

How does Nervous tissue generally repair?

Answer 56

Neurons do not undergo mitosis (amitotic); develop fibrotic scarring from glial cells. If the cell body of the neuron remains intact, a damaged axon outside of the brain or spinal cord may regenerate.

Question 57

Describe the process of regeneration.

Answer 57

Damaged or dead cells replaced with cells of the same type. Usually complete return of function.

Question 58

Explain the process of fibrosis.

Answer 58

Scar tissue formation composed of dense irregular CT | Fibroblasts mitotically divide to produce collagen to fill a defect. Tissue does not regain full functional ability.