Principles of histology

Question 1

What is histology?

Answer 1

It is the microscopic study of normal tissues and organs

Question 2

What is cytology?

Answer 2

It is the examination of a single cell type

Question 3

The cytoskeleton function

Answer 3

Cytoskeleton:
- supports the cell
- holds organelles in place
-helps in movement
- consists of filamentous proteins that reversibly assemble to allow remodelling

Question 4

Cytoskeleton filaments consist of…

Answer 4

1. Microfilaments- actin filaments
   2.intermediate filaments - in skin cells they resist strain
2. Microtubules - stiffer than actin filaments involved in segregation of chromosomes, movements of flagella/cillia

Question 5

functions of the endoplasmic reticulums

Answer 5

RER- contain ribosomes to synthesise proteins

SER- produces lipids and stores ca2+ in muscle cells

Question 6

Function of the Golgi apparatus

Answer 6

Concentrate and modify proteins and lipids from the ER and package the into either vesicles.

Question 7

Functions of vesicles

Answer 7

Secretory vesicles- secrete substances e.g insulin in islets of langerhans

Peroxisomes- contain enzymes that break down hydrogen peroxide, fatty acids and amino acids, found in the cells active in detoxification e.g liver cells

Question 8

Function of mitochondria

Answer 8

Have smooth outer and folded inner membranes enclosing the matrix

In animals, mitochondrial DNA inheritance is almost exclusively maternal- mutations in mitochondrial DNA are transmitted from mother to foetus
E.g - diabetes mellitus
- epilepsy
- proximal weakness
- cardiomyopathy

Question 9

Goblet cells are secretory cells that secrete…

Answer 9

Mucus

Question 10

Name the 4 primary tissue types

Answer 10

Epithelium
Connective tissue
Muscle tissue
Nervous tissue

Question 11

How is epithelium classified

Answer 11

Layers:
- simple (one)
- stratified (more than one)
- pseudostratified (one layer but looks like more)

Cell shape:
- squamous (flat)
- cuboidal
- columnar (tall)
- transitional (changing)

Question 12

Answer 12

Question 13

What do these suffixes mean
1.-blast
2.-cyte
3.-clast

Answer 13

1.build
2. Mature
3. Destroy

Question 14

What type of epithelium?

Answer 14

Simple cuboidal

Question 15

What type of epithelium?

Answer 15

Simple columnar

Question 16

What type of epithelium?

Answer 16

Simple squamous

Question 17

What type of epithelium?

Answer 17

Stratified squamous

Question 18

What type of epithelium?

Answer 18

Pseudostratified columnar

Question 19

What type of epithelium?

Answer 19

Transitional

Question 20

Extracellular matrix has 3 components

Answer 20

1. Fluid
2. Ground substance
3. Protein fibres (3)
   - collagen
   - reticular
   - elastic

Question 21

Exocrine glands secrete into…

Answer 21

A ductal system

Question 22

endocrine glands secrete into…

Answer 22

The bloodstream

Question 23

Answer 23

Question 24

Answer 24

Question 25

What is haemotoxylin

Answer 25

Basic (alkaline) dye that dyes basophilic (acidic) structures blue/purple E.g DNA in nucleus

Question 26

What is eosin

Answer 26

Acidic dye that dyes acidophilic (basic) structures pink. E.g proteins within the cytoplasm

Question 27

3 main techniques for preparing samples for histological analysis

Answer 27

- Paraffin technique - frozen sections - semithin sections

Question 28

Loose connective tissue consists of…

Answer 28

Loose arrangement of fibres (collagen, elastin) with other cells such as fibroblasts, adipocytes, plasma cells etc. E.g lymph gland

Question 29

Dense irregular connective tissue consists of…

Answer 29

Densely packed network of collagen and elastic fibres, fibroblasts are also present. E.g found in dermis

Question 30

What are fibroblasts

Answer 30

Primary cell of connective tissue

Question 31

Dense regular connective tissue consists of…

Answer 31

Densely packed collagen fibres running parallel to each other, fibroblasts and capillaries are still present. E.g ligaments