Tissues 1 - 2

Question 1

Define tissue.

Answer 1

Tissue is an ensemble of similar cells and their extracellular matrix from the same origin that carry out a specific function.

Question 2

What are the 4 basic types of tissues?

Answer 2

1) Epithelia
2) Connective
3) Muscle
4) Nerve

Question 3

Define epithelium.

Answer 3

The purely cellular avascular layer covering all free surfaces, cutaneous, mucous and serous, including the glands and other structures derived therefrom.

Question 4

What decides function?

Answer 4

Basic function (cells define function, diversity of secondary functions e.g movement – cilia, absorption - microvilli)

Question 5

What are the 4 basic functions of epithelial surfaces?

Answer 5

1) covers surfaces
2) Cells connected
3) Separates compartments
4) forms glands

Question 6

What is connective tissues main function? And what defines its function?

Answer 6

connects, extracellular matrix fluid defines structure and function.

Question 7

What is muscle tissues main function? And how does the structure allow for this?

Answer 7

contractile, - long thin cells,- cytoplasm of cells packed with contractile apparatus, -shorten lengths close down space

Question 8

What are the three types of muscles?

Answer 8

Cardiac
Smooth
Skeletal

Question 9

What is nerve tissue’s function?

Answer 9

communication:
formed of neurons and support cells
It receives, generates and transmits electrical signals
Integrates information (Makes decisions)

Question 10

How do epithelia cells stick together?

Answer 10

either Cell-cell junctions or cell-ecm junctions.

Question 11

What are the types of cell-cell junstions.

Answer 11

Desmosomes
Tight/ occluding Junctions
Gap junctions

Question 12

What are Desmosomes?

Answer 12

Desmosomes (aka adhering junctions) are a way of connecting epithelia cells which provides it with firm anchorage and mechanical strength. There are spaces between cells in this junction (not liquid tight).

Question 13

What are tight junctions?

Answer 13

Junctions that have very little space between cells to prevent liquid leaking out or in e.g in the intestine. This junction allows for cell-cell communication.

Question 14

What are gap junctions?

Answer 14

There a gaps left in stuctures such as cardiac muscle to allow for cell - cell communication.

Question 15

What does the histology of skeletal muscle look like?

Answer 15

Skeletal muscle: Striated, highly ordered arrangement of contractile protiens

Question 16

What does the histology of cardiac muscle look like?

Answer 16

Striated, highly ordered arrangement of contractile protiens

Question 17

What does the histology of Smooth muscle look like?

Answer 17

Non-striated (smooth) - less ordered arrangement of contractile proteins.

Question 18

Explain the difference between epithelium and endothelium

Answer 18

Epithelium is external, endothelium is internal.

Question 19

What makes up the basement membrane?

Answer 19

• Basement membrane = Basal lamina + Reticular lamina.