Histology Study Guide

Question 1

What is a tissue? What are the 4 types in the human body?

Answer 1

a group of specialized cells working together to perform a certain specific function
- muscle tissue
- nervous tissue
- epithelial tissue
- connective tissue proper

Question 2

What are the 2 forms of epithelium? Give an example of each.

Answer 2

• glandular epithelium:secretory tissue that covers the glands(ex: salivary glands)
• covering/lining epithelium: tissue that lines the internal and external surfaces of the body (ex: skin)

Question 3

Be prepared to distinguish the 5 characteristics of epithelial tissue.

Answer 3

• polarity
• specialized contacts
• regeneration
• avascular
• supported by connective tissue

Question 4

Define polarity. Be prepared to label the apical and basal surface of a pictured sample.

Answer 4

has two surfaces, both of which differ in function and structure
- apical surface: free/upper side
- basal surface: attached/bottom side. attaches to basal lamina

Question 5

What is a basement membrane? What two layers does it contain? What does it do?

Answer 5

• separates the epithelial tissue from connective tissue
• contains basal and reticular lamina
• it resists stretching/tearing, reinforces epithelial sheet, defines epithelial boundary

Question 6

What does it mean to be avascular but innervated?

Answer 6

no blood supply/blood vessels but has nerves

Question 7

What stimulates the start of epithelial regeneration?

Answer 7

loss of the apical-basal polarity/breaks in lateral contacts

Question 8

How do you classify epithelial tissue? Be prepared to classify a sample from a picture.

Answer 8

by the # of layers and by the shape of the individual cells. you refer to the epithelial tissue based on its apical (top) layer

Question 9

What is the function of transitional epithelia? Where might you find it?

Answer 9

• forms the lining of the hollow urinary organs.
• found in bladder, ureters, urethra
• cells can change shape to expand in order to hold fluid

Question 10

What is a gland? How do you classify glands? Be prepared to classify a gland by structure from a picture (like on slide 23!)

Answer 10

1+ cell that makes and secretes an aqueous fluid-a secretion
can classify by site of product release (internal-endocrine or external-exocrine) and the relative number of cells involved (unicellular or multicellular)

Question 11

Know the differences between endocrine and exocrine glands. And know a few examples of each.

Answer 11

Endocrine: don’t have ducts, secrete into interstitial fluid. secrete hormones that travel through blood to reach organs. example: pituitary glands
Exocrine: secrete into ducts, secretions are released onto body surfaces (like skin) or into body cavities (mucus, sweat, oil, salivary glands)

Question 12

What are some functions of connective tissue? What are the 4 types?

Answer 12

Binding, support, protection, insulation, reserve fuel, transportation of substance
- Bone
- Cartilage
- Connective tissue proper
- Blood

Question 13

What is something found in all types of connective tissue? What are its components?

Answer 13

• all connective tissue derives from mesenchyme
• its 3 main elements are ground substance, fibers, and cells
• ECM = ground substance and fibers

Question 14

Define ground substance. List the 3 types of fibers – what does each type look like?

Answer 14

unstructured gel like material that fills space between cells and where solutes diffuse between blood capillaries and cells
FIBERS:
- collagen: strong and thick (most abundant) high tensile strength
- elastic: long and thin allows stretch and recoil
- reticular: short, fine, highly branched, offer give

Question 15

What kinds of cells can be found in connective tissue? What’s the difference between a “blast cell” and a “cyte cell”?

Answer 15

• blast cells
• cyte cells
• fat cells
• white blood cells
• mast cells
• macrophages

cyte cells are more mature and less active than blast cells and become a part of and maintain the ECM, while blast cells secrete ground substance and ECM fibers

Question 16

List the 3 types of LCT. Know what each type is used for and where it is found.

Answer 16

• Areolar: supports and binds other tissue (packing material) found between skin and muscles (looks stringy)
• Adipose: energy storage, shock absorption, insulation, found under your skin and between internal organs (looks like bubbles)
• Reticular: stroma, acts as support for free blood cells, macrophages, mast cells in lymph nodes, the spleen, bone marrow (looks like a grapefruit)

Question 17

List the 3 types of DCT. Know what each type is used for and where it is found.

Answer 17

• Regular: high tensile strength, closely packed bundles of collagen fibers, appears wavy and organized, found in tendons and ligaments (ACL)
• Irregular: tangled and disorganized, resists tension from many directions, found in dermis, fibrous joint capsules, fibrous coverings of some organs
• Elastic: looks like a rough wall, found in ligaments connecting with adjacent vertebrae and found in walls of the large arteries (places that are very elastic)

Question 18

Is cartilage vascularized? Innervated?

Answer 18

cartilage is avascular and not innervated

Question 18

What are the 3 types of cartilage? Be familiar with where you could find each type.

Answer 18

• hyaline: tips of long bones, nose trachea, larynx, ribs
• elastic: ears and epiglottis
• fibrocartilage: in the knee and intervertebral discs

Question 19

What is an osteon? A lacuna?

Answer 19

osteon: individual structural units of the bone
- lacunae: cavities within the matrix where osteocytes reside

Question 20

Are bones vascularized? What is formed within bones?

Answer 20

bones are vascularized and forms blood cells

Question 21

What is the ECM of blood? When do you see fibers in blood?

Answer 21

ECM of blood = plasma
- you see fibers in blood during blood clotting

Question 22

What are the 3 types of muscle tissue? Which of these types are voluntarily controlled? Involuntarily?

Answer 22

• skeletal (voluntary)
• smooth (involuntary)
• cardiac (involuntary)

Question 23

What structural element facilitates the contraction of muscles?

Answer 23

myofilaments

Question 24

What is in an intercalated disc?

Answer 24

special joints where cardiac muscle cells are joined (represented by faint lines in cardiac muscle)

Question 25

What two types of cells are found within nervous tissue? Which of these types has the ability to generate and transmit impulses?

Answer 25

• neurons (have the ability to generate and transmit electrical impulses)
• glial cells: protect and insulate neurons

Question 26

What makes up a membrane? What are the 3 types?

Answer 26

composed of 2+ tissue types - epithelium bound to underlying connective tissue proper
- cutaneous membranes
- mucus membranes
- serous membranes

Question 27

Be familiar with what makes up each type of membrane. For example, stratified squamous epithelium + thick dermis = cutaneous membrane (skin).

Answer 27

• cutaneous: stratified squamous epithelium + thick dermis
• mucous: epithelial sheet lies over a layer of loose connective tissue called a lamina propria
• serous: simple squamous epithelium (mesothelium) lying on a thin layer of areolar connective tissue

Question 28

What’s the difference between tissue regeneration and fibrosis?

Answer 28

in tissue regen, the original function is restored and the same tissue regrows. in fibrosis, the destroyed tissue is replaced by scar tissue (DCT) and the original function is lost

Question 29

What are the 3 steps of tissue repair?

Answer 29

1. inflammation stage
2. organization restores blood supply
3. regeneration and fibrosis

Question 30

What kinds of tissues have high, moderate, and low capacities to regenerate?

Answer 30

high capacity: epithelial tissues, bone, areolar tissue, dense irregular connective tissue, blood-forming tissue
moderate capacity: smooth muscle, dense irregular connective tissue
low capacity: cardiac muscle, nervous tissue