structural organization in animals

Question 1

the organisation of a group of similar cells along intracellular substances performing a similar function in multicellular animals

Answer 1

tissues

Question 2

general features of epithelial

Answer 2

free surface faces either body fluid or outside environment; provides a covering or lining for some part of the body. compactly packed with little intercellular matrix

Question 3

On what basis are the cells of simple epithelium further divided into three types

Answer 3

On the basis of structural modification of the cells, simple epithelium
is further divided into three types

Question 4

Three types of simple epithelium

Answer 4

Squamous, Cuboidal, Columnar

Question 5

Features Squamous epithelium

Answer 5

• single thin layer of flattened cells with irregular boundaries

Question 6

Location of squamous epithelium

Answer 6

• Found in: walls of blood vessels, air sacs of lungs

Question 7

Function: Squamous epithelium

Answer 7

involved in functions like forming a diffusion boundary

Question 8

Features: Cuboidal epithelium

Answer 8

composed of a single layer of
cube-like cells

Question 9

Location: Cuboidal epithelium

Answer 9

commonly found in
1. ducts of glands
2. tubular parts of nephrons in kidneys
3. epithelium of proximal convoluted tubule (PCT) of nephron in the kidney has microvilli (brush bordered)

Question 10

Functions: Cuboidal

Answer 10

Secretion and Absorption

Question 11

Features: Columnar Epithelium

Answer 11

composed of a single layer of tall and slender cells. Their nuclei are located
at the base. Free surface may have microvilli.

Question 12

Location: columnar

Answer 12

lining of stomach and intestine

Question 13

function: columnar

Answer 13

secretion and absorption

Question 14

If the ____________ bear cilia on their free surface they are called ciliated epithelium

Answer 14

columnar or cuboidal cells

Question 15

function: ciliated

Answer 15

Their function is to move particles or
mucus in a specific direction over the epithelium.

Question 16

location: ciliated

Answer 16

inner surface of hollow organs like bronchioles and fallopian tubes.

Question 17

types: glandular

Answer 17

They are mainly of two types:
1. unicellular: isolated glandular cells (goblet cells of the alimentary canal)
2. multicellular: consisting of cluster of cells
(salivary gland)

Question 18

glandular on the basis of mode of pouring of secretion

Answer 18

exocrine and endocrine

Question 19

Exocrine glands secrete

Answer 19

mucus, saliva, earwax, oil,
milk, digestive enzymes and other cell
products. These products are released
through ducts or tubes.

Question 20

endocrine glands

Answer 20

do not have ducts. Their products called hormones are secreted directly into the fluid bathing the gland.

Question 21

function: compund epitheliummmmmm

Answer 21

Compound epithelium is made of more
than one layer (multi-layered) of cells and thus has a limited role in secretion and absorption. Their main function is to provide protection against chemical and mechanical stresses.

Question 22

location: compound epitheliyum :P

Answer 22

1. They cover the dry surface of the skin
2. the moist surface of buccal cavity
3. pharynx
4. inner lining of ducts of salivary glands and of pancreatic duct

Question 23

Types of cell junctions in epithelium and other tissues

Answer 23

1. Tight junctions help to stop substances
   from leaking across a tissue.
2. Adhering junctions perform cementing to
   keep neighbouring cells together.
3. Gap junctions facilitate the cells to
   communicate with each other by connecting the cytoplasm of adjoining
   cells, for rapid transfer of ions, small molecules and sometimes big molecules.