Chapter 4- Tissue level of organization

Question 1

4 Types of Tissue

Answer 1

1. Epithelial Tissue
   -Covers exposed surfaces
   -Lines internal passageways
   -Forms glands
   EX: skin, tubules of kidneys
2. Connective Tissue
   -Supports other tissues
   -Transports materials
   -Stores energy
   EX: adipose (fats)
3. Muscle Tissue
   -Specialized for contraction
   EX: Skeletal muscle, heart muscle, and walls of hollow organs
4. Neural Tissue
   -Carries electrical signals from one part of the body to another,

Question 2

Epithelial Tissue

Answer 2

CHARACTERISTICS: A lot of cells, Apical (free edge) & Basal (connects cells to body. connective) surface, avascular (no blood vessels), highly mitotic
FUNCTIONS: Protection, control, permeability, nerve sensations, produce secretions (sweat, sebum, hormones)
CELL JUNCTIONS: tight junctions, gap junctions, desmosomes

Question 3

Tight Junctions

Answer 3

Prevent passageway of fluid btwn cells

Question 4

Gap Junctions

Answer 4

Allow ion movement btwn cells

Question 5

Desmosomes

Answer 5

Prevent the cells from pulling apart, zipper likes attachments

Question 6

*Specializations of Epithelial Cells

Answer 6

1. Move fluids over the epithelium (protection)
2. Move fluids through the epithelium (permeability)
3. Produce secretions (protection and messengers)

Question 7

**Polarity

Answer 7

1. Apical surfaces
   - Microvilli, Cilia
2. Basolateral surfaces

Question 8

Microvilli

Answer 8

Increase absorption or secretion

Question 9

Cilia

Answer 9

Move fluid such as mucous

Question 10

Epithelia can easily be sorted into categories based on what two criteria?

Answer 10

Layers and Shape of cell

Question 11

What 3 basic shapes do epithelia possess?

Answer 11

Squamous, Cuboidal, Columnar

Question 12

Once you have determined the shape of the superficial cells, then you will need to look at the number of cell layers. You have two options, what are they?

Answer 12

Simple, Stratified

Question 13

*Simple Squamous Epithelium

Answer 13

-one layer thick, thin & flat
LOCATION: Serous membrane, lines blood vessels and heart, alveoli of lungs
FUNCTIONS: Reduce friction; controls vessel permeability absorption and secretions

Question 14

*Stratified Squamous Epithelium

Answer 14

-mult. layers thick, thin and flat apical surface
LOCATION: Skin, lining of mouth, throat, esophagus, anus & vagina
FUNCTIONS: Protect against physical abrasion, pathogens, and chemical attack

Question 15

*Simple Cuboidal Epithelium

Answer 15

-one layer, as tall as they are wide
LOCATION: glands & ducts, kidney tubules
FUNCTION: secretion, but some absorption

Question 16

*Transitional Epithelium

Answer 16

-mult. layers, varying shapes
LOCATION: Urinary tract
FUNCTION: Stretching and coiling

Question 17

*Simple Columnar Epithelium

Answer 17

-one layer thick, taller than they are wide
LOCATION: Stomach & intestines, uterine tubes, portions of kidney tubules
FUNCTION: Protection, secretion & absorption (microvilli)

Question 18

Pseudostratified Ciliated Columnar Epithelium

Answer 18

-mult. layers, false
LOCATION: Lines upper respiratory tract
FUNCTION: move mucus across apical surface with cilia

Question 19

*Endocrine epithelial glands

Answer 19

• Ductless

- Secrete hormones directly into blood (or ISF)

Question 20

*Exocrine epithelial glands

Answer 20

• Ducted

- Don’t secrete into blood but onto epithelial surfaces

Question 21

**Exocrine glands modes of secretion

Answer 21

1. Merocrine secretions
   -Released by cell by exocytosis
   EX: salivary glands
2. Apocrine secretions
   -Released from cell along w/ apical surface of cell
   EX: breast milk
3. Holocrine secretions
   -Whole cell bursts
   EX: sebaceous glands

Question 22

Connective Tissue

Answer 22

FUNCTIONS: Framework, transport nutrients & dissolved gases, protect delicate organs, support other tissue, store energy, defense against pathogens

Question 23

3 general categories of Connective Tissue

Answer 23

1. Connective tissue proper
   -connect and protect
   EX: loose and dense connective tissue
2. Fluid connective tissues
   -Transport
   EX: blood and lymph
3. Supporting connective tissue
   -Structural strength
   EX: cartilage and bone

Question 24

1. Two categories of connective tissue proper

Answer 24

• Loose connective tissue

- Dense connective tissue

Question 25

Loose connective tissue

Answer 25

-more ground substance. fewer fibers Ex: Fat (adipose) 1. Areolar Ex: collagen, elastic immune cells, fibrocytes F: Packing material & provide an arena for immune response** L: Dermis of skin, covered by epithelial lining of digestive, respiratory, and urinary tracts; btwn muscles, around joints, blood vessels and nerves 2. Adipose Ex: Adipocytes F: Cushioning and insulation, energy storage L: Subcutaneous, buttocks & breasts, padding around eyes & kidneys 3. Reticular Ex: Reticularfibers F: Structural support to some organs L: Liver, spleen, kidneys, lymph nodes, bone marrow

Question 26

Dense connective tissue

Answer 26

``` -more fibers, less ground substance Ex: tendons 1. Regular -collagen (parallel) F: Provide strength in one direction L: Tendons & ligaments ``` 2. Irregular -collagen (not parallel) F: Provide strength in all directions L: Dermis, outer coating of some organs

Question 27

2. Fluid connective tissues

Answer 27

Blood- transport oxygen and carbon dioxide, immune, transport nutrients & clotting Lymph- immune and transport leaked fluids back to the blood

Question 28

3. Supporting

Answer 28

Cartilage- Hyaline- present in joints, respiratory tract and immature skeleton Elastic- elastic fibers Fibrocartilage- collagen fibers Bone- support, internal storage of calcium & blood cell production

Question 29

Connective Tissue Fibers

Answer 29

Collagen fibers: strength Reticular fibers: small, branchy collagen fibers Elastic fibers: stretch and recoil

Question 30

Immune Cells

Answer 30

most cells - secrete histamine

Question 31

Fibroblasts

Answer 31

Produce connective tissue fibers

Question 32

Fibrocyte

Answer 32

Maintain connective tissue fibers

Question 33

Adipocyte

Answer 33

Energy storage

Question 34

Mesenchymal cells

Answer 34

Stem cells which can differentiate into fibroblasts

Question 35

Mast cells

Answer 35

Release histamine and heparin

Question 36

Macrophages

Answer 36

Phagocytes that engulf damaged cells or pathogens

Question 37

Lymphocytes

Answer 37

Defense of the body; some produce antibodies

Question 38

Melanocytes

Answer 38

Produce a brown pigment called melanin

Question 39

Many allergy sufferers take antihistamines to relieve their allergy symptoms. Which cells produce the molecule that this medication blocks?

Answer 39

Mast cells and basophils produce histamine

Question 40

Muscle tissue

Answer 40

Skeletal- voluntary muscles Smooth-line hollow organs (involuntary) Cardiac- heart (involuntary)

Question 41

Nervous tissue

Answer 41

Neurons- communication | Glial- support neurons

Question 42

Cells restore homeostasis with 2 processes

Answer 42

1. Inflammation | 2. Regeneration

Question 43

**** Inflammation

Answer 43

-The tissue's first response to injury, triggered by trauma/ infection Cardinal signs of inflammatory response include: Swelling, Redness, Heat, Pain Chemicals released by mast cells * Prostaglandins: cause pain, lets you know you're injured * Histamines: vasodilation, causes a leak of blood which causes localized edema (SWELLING) * *Increased blood circulation causes redness, heat, bringing more nutrients and oxygen; removing waste * Heparin: limits blood clotting * -*Histamines also cause heat, making cells replicate faster

Question 44

Regeneration

Answer 44

Fibrocytes move to the area and produce collagen, will get remodeled to look like original tissue by mitosis

Question 45

Age-related factors that affect tissue repair and structure

Answer 45

- Slower rate of energy consumption (metabolism) - Hormonal alterations - Reduced physical activity

Question 46

What would account for the observed increase in cancer rates with age?

Answer 46

- joint pain and broken bones - mental deterioration - cardiovascular disease