Lab 2: The Tissues

Question 1

What is a tissue? Not the kleenex kind…

Answer 1

A group of cells w/ similar structure and function plus extracellular substances located between cells.

Question 2

What the name of the microscopic study of tissues?

Answer 2

Histology

Question 3

What are the five basic tissue types?

Answer 3

Connective, blood, epithelial, muscle, nervous.

Question 4

What are the two major constituents of connective tissue?

Answer 4

Cells and extracellular material.

Question 5

What is the function of the extracellular material and what does it consist of?

Answer 5

Determines the physical properties of each type of connective tissue. Consists of a matrix of inorganic material called ground substances and within which are imbedded a variety of fibres.

Question 6

What are the two types of cells found in connective tissue?

Answer 6

Fibroblasts and adipocytes.

Question 7

What is the function of fibroblasts?

Answer 7

synthesis and maintenance of extracellular material

Question 8

What is the function of adipocytes?

Answer 8

storage and metabolism of fat

Question 9

What is the ground substance and its main components?

Answer 9

Amorphous material which have consistency of semi-fluid gel. Bounds tissue fluid, medium for material passing throughout CT, exchange of metabolites w/ circulatory system.
Components: glycosaminoglycans, proteoglycans (which bind to each other to form long chains, water, and positive ions (sodium)).

Question 10

What are the three main types of fibres that make up CT?

Answer 10

Collagen (most abundant protein in body), elastin (arranged as fibres, sheets), and structural glycoproteins (group of fibre forming molecules including fibronectin and laminin, associated w/ cell surface membranes.)

Question 11

What is blood?

Answer 11

A connective tissue made up of cells in plasma, exchanged w/ extracellular fluid medium of all tissues.

Question 12

What are the three types of functional classes of blood cells?

Answer 12

Erythrocytes, leukocytes, thrombocytes (platelets).

Question 13

What is the function of erythrocytes?

Answer 13

Involved in oxygen and carbon dioxide transport.

Question 14

What is the function of leukocytes?

Answer 14

Defense and immune systems of body

Question 15

What is the function of thrombocytes?

Answer 15

Clotting!

Question 16

What is plasma?

Answer 16

Aqueous solution of inorganic salts and proteins which is constantly being component of blood clotting.

Question 17

Where are cell types formed and what is the process called?

Answer 17

Bone marrow, hematopoiesis.

Question 18

What is the function of epithelia?

Answer 18

Lining all body surfaces, cavities, tubes - interfaces between biological components.

Question 19

What are epithelia supported by?

Answer 19

A basement membrane of variable thickness.

Question 20

Function of basement membranes?

Answer 20

Separate epithelia from underlying CT and are never penetrated by blood vessels; therefore epithelia are dependent on diffusion of oxygen and metabolites from underlying tissues.

Question 21

What are the three morphological characteristics that classify epithelia?

Answer 21

1) Number of cell layers (simple vs. stratified)
2) Shape of cells (squamous, columnar, etc,)
3) Presence of surface specializations. (eg cilia, keratin)

Question 22

What are the three types of muscle?

Answer 22

Skeletal, smooth, cardiac

Question 23

Features and function of skeletal muscle?

Answer 23

Voluntary, striated, multi-nucleated, all or none fashion. Movement of skeleton and organs (eg globe of eye and tongue).

Question 24

Features and function of smooth muscle?

Answer 24

Involuntary, mono-nucleated, not striated. Muscular component of visceral structures (eg blood vessels, digestive tract, uterus, bladder.) Under inherent, automatic, hormonal control.

Question 25

Features and function of cardiac muscle?

Answer 25

Involuntary, striated, mono-nucleated, fast all or none fashion - intercalated structure. Continuous, rhythmic contractility of heart.

Question 26

What are the striations in some muscles?

Answer 26

Contractile proteins that are arranged to make prominent cross striations that appear in histological preparations.

Question 27

What is the nervous system composed of?

Answer 27

Variation in arrangement of neurons and their supporting tissues. Neurons constitute most sensory receptors, conducting pathways, sites of integration and analysis.

Question 28

Parts of microscope? Here's five...

Answer 28

Eyepiece w/ lens, objective lens, arm, focus knobs, base w/ light source.

Question 29

General function of connective tissue?

Answer 29

To support and "connect" body parts and to protect body from bacteria.

Question 30

What are the three kinds of CT?

Answer 30

Structural, defensive, sequestering.

Question 31

3 arrangements of CT?

Answer 31

Dense regular CT - connect bones and muscles Dense irregular - thick layer of skin Areolar - flexible

Question 32

What are the structural elements of the skin which are responsible for its physiological functions?

Answer 32

Stratified squamous epithelial tissue (lines outside) and dense irregular tissue CT (underneath dermis). Function: forming protective layer to body.

Question 33

What are the three types of cartilage? Differentiate between them

Answer 33

1) Hyaline - reduces friction in joints and at ends of long bones. 2) Elastic - in external ear, consists of cartilage and elastic fibres. 3) Fibrocartilage - mix of cartilage and collagen (protein in CT).

Question 34

What is the extracellular matrix and how is it produced/maintained?

Answer 34

Aka ground substance. Consists of glycosaminoglycans and proteoglycans. Chondrocytes, which make up cartilage, secrete and degrade matrix when necessary.

Question 35

Histological structure of bone?

Answer 35

Have harvesian canals, which allow nerves and blood to flow through. They are surrounded by lamellae, which in turn are surrounded by spongy and compact bone.

Question 36

What is the difference between spongy and compact bone?

Answer 36

Spongy bone has pores, Compact is denser w/ collagen fibres.

Question 37

Three cell types found in bone and their functions?

Answer 37

1) Osteoclasts - dissolve bones 2) Osteoblasts - form new bones 3) Osteocytes - regulate calcium levels in bloodstream.

Question 38

6 types of connective tissue covered in lab?

Answer 38

Dense regular, dense irregular, areolar, reticular, elastic, adipose.

Question 39

8 types of epithelium covered in lab?

Answer 39

1) Simple squamous 2) Stratified squamous 3) Stratified squamous keratinising 4) Simple cuboidal 5) Simple columnar 6) Simple columnar ciliated 7) Pseudostratified columnar 8) Transitional

Question 40

3 types of muscle tissue covered in lab?

Answer 40

Skeletal, smooth, cardiac plus their cross sections.

Question 41

2 nervous tissues covered in lab PPT slides?

Answer 41

Motor end plates, peripheral nerve.