Class 5 - Human Tissues

Question 1

Tissue

Answer 1

A group of similar cells and cell products working together to perform a specific role in an organ

Question 2

Matrix/extracellular material composition (2)

Answer 2

1. Fibrous proteins
2. Ground substance aka ECF; contains water, gases, minerals, nutrients, wastes, hormones

Question 3

The four primary tissues

Answer 3

1. Epithelial
2. Connective
3. Nervous
4. Muscular

Question 4

3 germ layers and what arises from them

Answer 4

1. Ectoderm - Epidermis and nervous system
2. Mesoderm - Cartilage, bone, blood
3. Endoderm - Mucous membrane lining digestive and respiratory tracts, digestive glands

Question 5

Things used in tissue sections (2), types of sections (3), other tissue samples (2)

Answer 5

1. Fixative to prevent decay
2. Stain to color tissue

a. Longitudinal section
b. Cross section
c. Oblique section

1. Smear - Spread on
2. Spread - Laid out

Question 6

Epithelial tissue

Answer 6

Sheet of closely adhering cells, with upper surface exposed to environment or internal space.

Small amount of ECM.

High rate of mitosis in cells near connective tissue.

Rest on basement membrane, which anchors it to underlying connective tissue

Covers body surface and lines body cavities. Constitutes most glands.

Avascular; nourished by underlying connective tissue

Question 7

Functions of epithelial tissue (6)

Answer 7

1. Protection - Against deeper tissue injury and infection
2. Secretion - Produce/release sweat, mucus, enzymes, hormones
3. Excretion - Void wasted from tissues
4. Absorption - Absorb chemicals/nutrients
5. Filtration - Substances leaving body are selectively filtered by epithelium
6. Sensation - Nerve endings embedded in epithelia detect stimuli

Question 8

3 surfaces of epithelial cells

Answer 8

1. Basal - bottom
2. Apical - top
3. Lateral - side

Question 9

Four types of simple epithelium, characteristics, and locations

Answer 9

1. Simple squamous - Rapid diffusion/substance transport. Secretes serous fluid.
   Locations: Alveoli, glomeruli, endothelium, serosa
2. Simple cuboidal - absorption/secretion, mucus production/movement.
   Locations: Liver, thyroid, mammary/salivary glands, bronchioles, kidney tubules.
3. Simple columnar - Goblet cells. Absorption/secretion, mucus. Nuclei typically in basal half. Brush border, sometimes ciliated.
   Locations: Lining of GI tract, uterus, kidney, uterine tubes.
4. Ciliated Pseudostratified columnar - Goblet cells. Secretes/propels mucus.
   Locations: Respiratory tract and male urethra

Question 10

Four types of stratified epithelia, characteristics, and locations

Answer 10

1. Stratified squamous - Most widespread
   Location: skin
2. Stratified cuboidal - Secretes sweat, produces sperm, produces ovarian hormones.
   Locations: Sweat gland ducts, ovarian follicles, seminiferous tubules
3. Stratified columnar - Rare; only in places where two other epithelial types meet.
4. Urothelium - cells change from round to flat when stretched; allows filling of urinary tract
   Locations: ureter and bladder.

Question 11

Two kinds of stratified squamous epithelia

Answer 11

1. Keratinized - Found in skin surface, dead skin layer, abrasion resistant, retard water loss
   Locations: epidermis; palms and soles especially
2. Nonkeratinized - Found lining internal spaces, lacks surface layer of dead cells, resists abrasion/pathogen penetration
   Locations: Tongue, oral mucosa, esophagus, vagina