CELL JUNCTIONS - SURFACE EXTENTION

Question 1

Transmembrane proteins form channels for small molecules to move between the cytoplasm of neighboring cells .

Answer 1

Gap junction

Question 2

strength junction between the cells , makes the cells as a unit in the tissue .

Answer 2

tight junction

Question 3

intermediate filaments located in between the neighboring cells

Answer 3

desmosome

Question 4

a sticky junction where the transmembrane protein fibers adhere to each other in the extracellular matrix

Answer 4

Adherens junction

Question 5

intermediate filaments located at the base of the cell, which attach the cell to the basement membrane

Answer 5

Hemidesmosomes

Question 6

extensions of the plasma membrane that serve primarily to increase a cell’s surface area for absorption, such as the epithelial cells of the intestines and kidney tubules. They give such cells 15 to 40 times as much absorptive surface area as they would have if their apical surfaces were flat

Answer 6

Microvilli

Question 7

Hairline processes about 7 to 10 µ long , Nearly every human cell has a single, nonmotile primary cilium a few micrometers long. Its function in many cases is still a mystery, but some of them are sensory , beat in waves that sweep across the surface
of an epithelium, always in the same direction

Answer 7

Cilia

Question 8

are less widespread, occurring mainly in the respiratory tract and the uterine (fallopian) tubes. There may be 50 to 200 of these are on the surface of one cell.

Answer 8

Motile Cilia

Question 9

a core called the axoneme, which consists of an array of thin protein cylinders called microtubules , There are two central microtubules surrounded by a ring of nine microtubule pairs—an arrangement called the 9+2 structure , The central microtubules stop at the cell surface, but the peripheral microtubules continue a short distance into the cell as part of a basal body that anchors , In each pair of peripheral microtubules, one tubule has two little dynein arms. Dynein, a motor protein, uses energy from ATP.

Answer 9

The structural basis for ciliary movement

Question 10

Whip like structure much longer than a cilium, but with an identical axoneme , e.x. the tail of a sperm cell .

Answer 10

Flagella

Question 11

temporary extensions of the plasma membrane used for movement or to engulf particles

Answer 11

Pseudopodia