GENERAL HISTOLOGY

EPITHELIUM

CELL JUNCTION

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
The membranes of cells are spot welded together to form reinforced structural units. Skin cells have these kind of junctions.
A
gap junctions
B
tight junctions
C
desmosomes
D
None of the above
Explanation: 

Detailed explanation-1: -Animal cells may also contain junctions called desmosomes, which act like spot welds between adjacent epithelial cells. A desmosome involves a complex of proteins. Some of these proteins extend across the membrane, while others anchor the junction within the cell.

Detailed explanation-2: -Epithelial cells are held together by strong anchoring (zonula adherens) junctions. The adherens junction lies below the tight junction (occluding junction). In the gap (about 15-20nm) between the two cells, there is a protein called cadherin-a cell membrane glycoprotein.

Detailed explanation-3: -In vertebrates, there are three major types of cell junction: Adherens junctions, desmosomes and hemidesmosomes (anchoring junctions) Gap junctions (communicating junction) Tight junctions (occluding junctions)

Detailed explanation-4: -Cell junctions fall into three functional classes: occluding junctions, anchoring junctions, and communicating junctions. Tight junctions are occluding junctions that are crucial in maintaining the concentration differences of small hydrophilic molecules across epithelial cell sheets.

There is 1 question to complete.