1. __________ is caused due to endothelial damage.
a) Atherosclerosis
b) Cancer
c) Alzheimer’s Disease
d) Ringworm
Explanation: Atherosclerosis is caused due to endothelial damage. Cancer is caused due to the accumulation of damaged genes products. Like all types of Dementia, Alzheimer’s disease is caused due to brain-cell death. Ringworm is a contagious fungal infection caused by mold-like parasites living on cells of the outermost layer of the skin.
2. ____________ is the process by which cells interact and attach to neighboring cells through specialized molecules of the cell surface.
a) Cell Migration
b) Cell Division
c) Cell Development
d) Cell adhesion
Explanation: The process by which cells interact and attach to each other is termed as cell adhesion. This is done through specialized cells on their surface. Cell adhesion could either be due to direct contact between the surfaces of the cells or by indirect interaction, in which cells attach to the extracellular matrix (ECM).
3. __________ aid in the process of cell adhesion.
a) Cell receptors
b) Transmembrane proteins
c) Protease
d) Cytokinins
Explanation: The interactions among the cell-adhesion molecules (CAMs) result in a phenomenon called Cell adhesion. In general, the cell-adhesion molecules are the trans-membrane proteins located on the cell’s surface.
4. _____________ is a hemophilic cell-adhesion molecule.
a) Cadherins
b) Integrins
c) Selectins
d) Antibody
Explanation: Cell adhesion molecules (CAMS) are classified into four categories: selectins, integrins, cadherins, and immunoglobulins (Ig). Each of the CAMs has a particular function and they recognize a different ligand. Cadherins and immunoglobulins are homophilic CAMs, since they bind to the same type of CAMs on another cell, while integrins and selectins are heterophilic CAMs that bind to different types of CAMs.
5. Cell adhesion is also essential for infectious organisms, such as bacteria or viruses, to cause diseases.
a) True
b) False
Explanation: Variations in cell adhesion can cause disruptions in major cellular processes and cause a number of diseases like cancer and arthritis. Cell adhesion is also essential for infectious organisms, such as bacteria or viruses, to cause diseases.
6. Plants cells adhere closely to each other and are connected through __________
a) plasmodesmata
b) stomata
c) parenchyma
d) stroma
Explanation: Plants cells adhere closely to each other and are attached through the plasmodesmata. These are channels crossing the plant cell walls and connect the cytoplasm of neighboring plant cells.
7. HIV has an adhesion molecule termed hemagglutinin that binds to its ligand CD4.
a) True
b) False
Explanation: Viruses have molecules aiding in adhesion of viral cells to the host cells. The influenza virus has adhesion molecules termed hemagglutinin on its surface; it helps in the recognition of sugar sialic acid molecules on the molecules on the host cell surface. HIV has an adhesion molecule called gp120 that binds to the CD4 ligand.
8. Selectins mediate the movement of keratinocytes.
a) True
b) False
Explanation: Selectins are a category of specialized CAMs that are involved in transient cell-cell adhesion occurring in the circulatory system. They mainly mediate the movement of the WBCs in the bloodstream by allowing the white blood cells to slide on endothelial cells through reversible bindings of selections.
9. __________ have adhesion molecules on their cell surface termed bacterial adhesins.
a) Prokaryotes
b) Reptiles
c) Birds
d) Humans
Explanation: Prokaryotes have adhesion molecules on their cellular surface termed bacterial adhesins. These adhesins have the ability to recognize a number of ligands present on the host’s cellular surface and also the components in the Extracellular matrix (ECM).
10. Cells have specific CAMs that will bind to molecules in the extracellular matrix.
a) True
b) False
Explanation: Cells create ECM by filling the surrounding extracellular space with molecules. Cells have specific CAMs that will bind to molecules in the ECM and link the matrix to the intracellular cytoskeleton. These links are termed as cell-matrix junctions.