2a Epithelial And Nervous Tissues

Question 1

What is tissue and what are the types?

Answer 1

Group of cells similar in structure that work together to perform one or more specific function
Epithelial, Muscle, Connective, Nervous

Question 2

What does nervous tissue do/is it responsible for? Composition?

Answer 2

In charge of internal communication
Composed of brain, spinal cord and nerves

Question 3

What does muscle tissue do? Types and their placement?

Answer 3

Contracts to cause movement
Skeletal muscle: muscle attached to bone
Cardiac muscle: muscle of heart
Smooth muscle: muscles of walls of hollow organs

Question 4

What does epithelial tissue do? Functions and locations?

Answer 4

Forms boundaries between different environments, protects, secretes, absorbs, filters
Skin surface (epidermis)
Lining of GI tract organs and other hollow organs

Question 5

What does connective tissue do? Examples?

Answer 5

Supports, protects, binds other tissues together
Bones, Tendons, Fat and other soft padding tissue

Question 6

What are some general characteristics of epithelial tissue (epithelium)?

Answer 6

Cells fit closely together to form sheets
Apical (free) and basal surfaces
Avascular
Will regenerate easily if well nourished

Question 7

What are some locations of epithelial tissue?

Answer 7

Glands
Lining of ventral body cavities
Innermost lining of ducts, vessels, and tubes
Skin
Surface lining of internal organs
(GLISS)

Question 8

What are the main functions of epithelial tissue?

Answer 8

Protection
Absorption
Secretion
Sensory reception
Excretion
Filtration
(PASSEF)

Question 9

How are continuous sheets of epithelial tissue formed?

Answer 9

Through specialized contact points called tight junctions and desmosomes found in adjacent epithelial cells

Question 10

What is a tight junction?

Answer 10

An impermeable junction that prevents molecules from passing through the intercellular space (made of special proteins)

Question 11

What is a desmosome?

Answer 11

Anchoring junctions that bind cells together like Velcro (also specific proteins)

Question 12

What and where is the reticular lamina?

Answer 12

It’s a network of collagen fibers deep/under the basal lamina

Question 13

What are the parts, from deep to superficial, of the basement membrane in epithelial cells?

Answer 13

Reticular Lamina-> Basal Lamina=basement membrane

Question 14

What is the difference between the basal lamina and the basal surface?

Answer 14

The basal surface refers to the part of the cell that is in contact with the basement membrane whereas the basal lamina refers to a layer in the extracellular matrix (part of the basement membrane)

Question 15

What does the basement membrane do?

Answer 15

It reinforces the epithelial sheet and resists stretching and tearing
It also defines the epithelial boundary (cell to connective tissue)

Question 16

What type of tissue is the basement membrane a part of?

Answer 16

Connective

Question 17

How do epithelial cells obtain nutrients if they are avascular?

Answer 17

Simple diffusion

Question 18

What are the ways of classifying epithelium? Name them.

Answer 18

By number of cell layers: Simple or Stratified
By cell shape: Squamous or Cuboidal or Columnar

Question 19

What are the function and structure of simple squamous epithelial cells?

Answer 19

Single layer of flat cells
Diffusion, Filtration, Secretion

Question 20

Where are simple squamous epithelial cells found?

Answer 20

Serous membranes
Walls of capillaries
Lines the heart
Lines the air sacs of lungs

Question 21

What are some other sub classifications of simple squamous epithelium and their locations?

Answer 21

Endothelium: simple squamous epithelium lining specifically blood cells, lymphatic vessels and the chambers of the heart
Mesothelium: simple squamous epithelium of serous membranes in the ventral body cavities

Question 22

What are the function and structure of simple cuboidal epithelial cells?

Answer 22

Single layer of cube-shaped cells
Absorption and Secretion

Question 23

Where are simple cuboidal epithelial cells located?

Answer 23

Walls of kidneys
Glands
Ducts
Covers the surface of ovaries

Question 24

What are the structure and function of simple columnar epithelial cells?

Answer 24

Single layer of tall column-like cells
Secretion, absorption and ciliated cells move mucous

Question 25

What are some distinct features of simple columnar epithelial cells?

Answer 25

Presence of goblet cells (mucous secreting cells) Presence of microvilli or cilia on the apical side

Question 26

Where are simple columnar epithelial cells located?

Answer 26

Lines digestive tract Uterine tubes Bronchi (LUB)

Question 27

What are the structure and function of pseudo-stratified columnar epithelial cells?

Answer 27

Single layer of columnar cells All cells rest on basement membrane Secretion and absorption

Question 28

Where are pseudostratified columnar epithelial cells located?

Answer 28

Ciliated: Trachea and upper respiratory tract Non-ciliated: Vas Deferens

Question 29

What are some distinct features of pseudostratified columnar epithelial cells?

Answer 29

They are all of different sizes which gives a false impression of stratification Nuclei are not all at the same level

Question 30

What are the structure and function of stratified squamous epithelial cells?

Answer 30

The apical surface is layered with squamous cells, but not necessarily the deeper layers Protection in areas where friction is common

Question 31

Where is stratified squamous epithelium located?

Answer 31

Moist linings (mouth, esophagus) Outer lining of skin

Question 32

What type of epithelial cells are skin cells and why are they said to be dead?

Answer 32

Stratified squamous epithelial cells The dead cells are keratinized and no longer have access to nutrients as new cells grown from the basement membrane

Question 33

What are the structures and functions of stratified cuboidal AND columnar epithelial cells?

Answer 33

Cuboidal: typically two layers of cuboidal cells Columnar: apical cells are columnar but the under layers vary in size and shape Function of both: Protection

Question 34

Where are stratified cuboidal and columnar located?

Answer 34

In the ducts of large glands (sweat, esophageal glands)

Question 35

What are the structure and function of transitional epithelial cells?

Answer 35

Cell shape depends on the amount of stretching To stretch and return to original shape

Question 36

Where is transitional epithelium located?

Answer 36

In the lining of hollow urinary system organs (bladder, ureters, urethra)

Question 37

What are glandular epithelial cells? (Glandular epithelia)

Answer 37

One or more cells that makes and secretes an aqueous fluid

Question 38

What is the difference between endocrine and exocrine glands?

Answer 38

Endocrine: internal secretion of hormones directly into the bloodstream Exocrine: secretion of products into ducts that empty onto the body surface, into spaces within organs or into a body cavity

Question 39

How is glandular epithelia classified? Specify.

Answer 39

Site of production release: endocrine (internally) or exocrine (externally) Number of cells forming the gland: unicellular (goblet cells) or multicellular (salivary)

Question 40

What is an example of a unicellular exocrine gland? Describe it.

Answer 40

Goblet cells: produces and secretes mucous, found in respiratory and intestinal tracts

Question 41

What does the nervous system do?

Answer 41

Main control system for the body Found in the brain, spinal cord and nerves Regulated and controls body functions Receives sensory input and integrates info, responds to stimuli

Question 42

What are the 2 types of nervous cells? Describe them.

Answer 42

Neuron: generates and transmits nerve impulses between parts of the nervous system Neuroglia: support, nourish and protect neurons