Tissues

Question 1

What is tissue?

Answer 1

group of similar cells for a specific function.

Question 2

4 primary tissue types

Answer 2

1. Epithelial tissue
2. Connective tissue
3. Muscle tissue
4. Neural (nerve) tissue

Question 3

Epithelium 2 types

Answer 3

Epithelia
• layers of cells covering internal or external surfaces.
Glands
• structures that produce secretions.

Question 4

Epithelium functions

Answer 4

Protection/lining/covering
Control permeability i.e. absorption, filtration
Produce secretions
Provide sensation

Question 5

Epithelium characteristics

Answer 5

Cells are very tightly packed together. Little extracellular material (matrix). Avascular (i.e., no blood vessels are present). Grow rapidly, high turnover (labile). Different on exposed versus attached surface (polar).

Question 6

Epithelium specializations (not present in all cells)

Answer 6

Microvilli increase surface area on the cell membrane. Cilia to beat/ contract in unison. Keratin waterproofs the cell. Polarity.

Question 7

Epithelium structure and morphology

Answer 7

Determined by number of layers and shape.
Number of layers:
Simple- Single layer
Pseudostratified- Single layer but the nucleus are at different points in the cell.
Stratified- Layered
Shape:
Squamous- Flat and thin
Cuboidal- Square boxes
Columnar- Tall and thin columns

Question 8

Transitional epithelium tissue cell layer.

Answer 8

When relaxed cuboidal but when stretched squamous.

Question 9

Connective tissue functions

Answer 9

Most abundant tissue in the body.
Functions are:
Supports and binds other tissues, provides insulation and protection, transporting fluid and dissolved materials and stores energy.

Question 10

Most connective tissues have the same basic construction of what?

Answer 10

Background matrix / extracellular matrix
• Protein fibres (e.g., collagen)
• Ground substance
• Cells (e.g., fibroblasts and macrophages)

Question 11

Connective tissue line map

Answer 11

Embryonic:
Mesenchyme and mucus
Mature:
Fluid connective tissue (blood and lymph)
Supportive connective tissue (Bone and cartilage)
Connective tissue proper (Loose (Areolar, adipose and reticular) and dense (regular, irregular and elastic))

Question 12

Visible differences between epithelial and connective tissue

Answer 12

epithelial have many cells tightly packed, little to no extracellular matrix, vascular.
connective has few scattered cells large amounts extracellular matrix and highly vascular (usually).

Question 13

Muscle tissue functions

Answer 13

Facilitates movement
Maintains joints stability
Provides postural control
Produces heat

Question 14

3 muscle tissue types

Answer 14

Skeletal-Voluntary control. Cells are long, cylindrical, straited and multi-nuclear. located combined with connective and neural tissue in the skeletal muscles. Functions are to move/ stabilize the position of the skeleton, guards entrances and exits to the digestive, respiratory and urinary tract, generates heat and protects internal organs

Cardiac- Involuntary control. Cells are short, branched, straited and usually with a nucleus. Cells are interconnected by intercalated discs. Located in the heart. Functions are to circulate the blood throughout the body and to maintain blood (hydrostatic) pressure.

Smooth- Involuntary, non-straited with a single central nucleus. Found in the walls of blood vessels and in digestive, respiratory, urinary and reproductive organs. Its function is to move food, urine, reproductive tract secretions. It controls diameter of respiratory passageways. regulates diameter of blood vessels.

Question 15

Neural tissue function and 2 types

Answer 15

Primary function is communication
• Types
• Neurons (nerve cells)
• Neuroglia (support cells). Maintains physical structure of tissues, repairs tissue framework after injury, perform phagocytosis (eliminating particles larger than 0.5 μm in diameter), provides nutrients to neurons and regulates the composition of interstitial fluid surrounding neurons

Question 16

Neuroglia (support cells) functions (5)

Answer 16

Maintains physical structure of tissues, repairs tissue framework after injury, perform phagocytosis (eliminating particles larger than 0.5 μm in diameter), provides nutrients to neurons and regulates the composition of interstitial fluid surrounding neurons