Chapter 4: Tissue Level Organization

Question 1

Name the 4 different types of human tissue.

Answer 1

Epithelial Tissue
Connective Tissue
Muscle Tissue
Nervous Tissue

Question 2

Describe the characteristics and functions of epithelial tissue. Examples of structures and locations.

Answer 2

Lines every body surface and all body cavities.
Constitutes most glands
One or more layers of closely packed cells form a barrier
Composed of cells bound by cell junctions

3 surfaces:
Apical surface (top surface)
Intercellular junctions (lateral surface)
Basal surface (fixed, bottom surface) - bound to basement membrane

Lacks blood vessels so nutrients are obtained directly across apical surface or by diffusion across basal surface.

Some is richly innervated.

High regeneration capacity - continual replacement

Functions:
Protection (skin)
Regulation of materials in/out of organ tissue
Produce secretions
The Senses

Question 3

Describe the characteristics and functions of connective tissue. Examples of structures and locations.

Answer 3

Binds body structures together.
Most diverse and abundant tissue.
Examples: cartilage, bone, blood, tendons/ligaments, fat

Function:

• Support (bones)
• Protect (skin, bones),
• Bind structures (tendons, ligaments)
• Storage (fat)
• Transport (blood)

3 Basic components:

• cells
• protein fibers
• ground substance

CELL TYPES
Connective tissue contains fibroblasts which regenerate tissue; Fat - adipocyte; Cartilage - chondrocytes; Bone - osteocytes; white blood cells etc for phagocytosis

PROTEIN FIBERS
throughout the tissue; strengthen and support; collagen, elastic and reticular fibers

Loose and Dense types
Loose - cushions organs (adipose)
Dense - everything else (tendons, skin, stomach)

Question 4

Describe the characteristics and functions of muscle tissue. Examples of structures and locations.

Answer 4

Respond to stimulation from the nervous system
Voluntary and Involuntary movements

3 types
Skeletal (striated) - voluntary
Smooth (non-striated) - Involuntary i.e. stomach, intestines
Cardiac (striated) - Involuntary - heart

Question 5

Describe the characteristics and functions of nervous tissue. Examples of structures and locations.

Answer 5

Consists of neurons and glial cells

Functions:
Detect stimuli, process info fast, transmit impulse from one region of the body to another

processingm storage, and retrieval; internal communication.

Question 6

Discuss tissue damage, repair, and death

Answer 6

Metaplasia: Tissue starts as one tissue and becomes another.
Hypertrophy: CELL gets bigger
Hyperplasia: AMOUNT of cells increases
Regeneration: Regrowth
Neoplasia: Out of control growth - cancer
Fibrosis: scar tissue
Atrophy: Shrinking of tissue either by cell size or number.

Question 7

Define tissues.

Answer 7

Group of similar cells and extracellular products that carry out a common function.

Question 8

Basic functions and types of epithelial tissue.

Answer 8

Simple: One layer; Absorption/secretion

Stratified: Many layers; Protection/secretion

Shapes: Squamous, cuboidal, columnar, transitional.

Question 9

Name the 4 types of cell junctions.

Answer 9

• tight junctions: “gate keepers” between external and internal environment
• adhering junctions: deep to tight junctions
• desmosomes: “snap” little piece connecting cells
• gap junctions: “tunnel” that connects one cell to another so items can pass through i.e. glucose (like the can and string example - allows communication between cells)

Question 10

Endocrine Glands

Answer 10

Secrete directly into the blood stream. i.e. hormones

Question 11

Exocrine Glands

Answer 11

Maintain contact with surface via a duct. Duct secretes materials on the skin surface or lining of internal passageway.

simple or compound glands; tubular (tubes) or acinar (sacs) or tubuloacinar (both) ducts

Question 12

Describe the differences between:
Merocrine glands
Holocrine glands
Apocrine glands

Answer 12

Merocrine glands: package secretions in vesicles and release by exocytosis i.e. salivary glands, gastric glands,

Holocrine glands: secretion produced by destruction of cell i.e. sebaceous glands

Apocrine glands: “decapitation,” top of cell squeezes off i.e. sweat glands/mammary glands

Question 13

Cartilage

Answer 13

3 types
Hyaline - ends of bones (i.e. also nose, trachea)

Fibrocartilage - more firm, not as flexible (i.e. meniscus, vertebral discs)

Elastic - bend it and it goes back to it’s shape (i.e. external ear)

Question 14

Bone

Answer 14

3 layers
Periostium - outer sheath surrounds bone but not on the ends

Compact - structure is close together, strong, small holes

Spongy - bigger holes, toward middle of the bone

osteocytes make and maintain regrowth of bone

Question 15

Fluid Connective Tissue

Answer 15

Blood
(erythrocytes) red blood cells - transport O2 and CO2
(leukocytes) white blood cells - antibodies
platelets - clotting factor

Question 16

Which primary tissue would be located in blood, body fat, ligaments and tendons, dermis of the skin, and in cartilage of some joints?

Answer 16

Connective Tissue

Question 17

What tissue type covers surfaces and lines the inside of organs and body cavities?

Answer 17

Epithelial Tissue