Cellular Biology Intro

Question 1

1. State three representative components critical for any tissue engineering design

Answer 1

cells, scaffold, construct, engineered tissue or organ

Question 2

2. Draw a basic structure of a cell. Label three cell components and state their function

Answer 2

Do

Question 3

3. State two function of cell plasma membrane

Answer 3

– Barrier to unwanted materials

– Maintenance of proper ionic composition, pH, osmotic pressure

– Contact with other cells and extracellular matrix

– Cell signaling receptors

– Nutrient transport in/waste transport out

Question 4

4. State two type of cell death processes and briefly differentiate between the two

Answer 4

necrosis- localized death of living cells (as from infection or the interruption of blood

-apoptosis- a type of cell death in which the cell used specialized cellular machinery to kill itself, often done to control cell number and kill out cells that threaten the animal’s surival

Question 5

5. State two type of cell contact and membrane receptors

Answer 5

cell contact- tight junction, gap junction, desmosomes

cell membrane receptors- cadherins, selectins

Question 6

6. State and describe a component of the extra cellular matrix (ECM)

Answer 6

collagen- responsible for tissue tensile strength, formed from a triple helix of polypeptide chains called aplha chains

elastin- forms fibers that allow for large elastic deformation which is responsible for extensiblity of the ECM

Question 7

7. Draw and describe the cell proliferation cycle

Answer 7

Do

Question 8

8. State two components that form the cytoskeleton

Answer 8

• intermediate filaments
• actin filaments
• microtubules

Question 9

9. Describe briefly steps associated with cell migration

Answer 9

1. extension-Protrusion of membrane lamellopodia
2. attachment-adhesion to matrix via integrins
3. contraction-contraction of cytoplasm
4. release-rear release and cell displacement
5. recycling-recycling of integrins

Question 10

10. Describe paracrine / autocrine soluble factor signaling

Answer 10

secreted molecules are not allowed to diffuse too far due to entrapment by ECM or degradation

Question 11

12. Name and describe three types of cell contacts?

Answer 11

tight junction, gap junction, desmosomes

Question 12

13. State and elaborate on the common forms of cell injury

Answer 12

• hypoxic injury: lack of oxygen= reduced blood supply
• Free radicals/reactive oxygen species injury-repurfusion (restoration of oxygen)
• chemical injury- cell is damaged from chemicals

Question 13

14. Define cell.

Answer 13

the basic living, structural and functional unit of all organisms

Question 14

15. Name and describe the adoptive response of cells to stress.

Answer 14

– Atrophy: decrease in size
– Hypertrophy: increase in size of cells
– Hyperplasia: increase in cell number
– Metaplasia: transformation from one cell type to another

Question 15

16. What is the function of the mitochondria in the cell?

Answer 15

produces most of the cell’s ATP

Question 16

17. Which one is not a membrane receptor?
    a. Cadherins
    b. Selectins
    c. Mucins
    d. Elastin
    e. Integrins

Answer 16

Elastin

Question 17

18. Differentiate between hypertrophy and hyperplasia.

Answer 17

hypertrophy- increase in size of cells

hyperplasia- increase in cell number

Question 18

19. Name and give the functions of three organelles found in a typical human cell.

Answer 18

centrioles- important in cell division

mitochondria- produces most of the cells of ATP

ribosomes- protein synthesis

Golgi apparatus- modifies and packages proteins, especially those for excretion

Question 19

20. What is cell differentiation

Answer 19

• Differentiation is a process by which cell undergoes phenotypic changes to an overtly specialized cell

Question 20

21. What is tissue engineering?

Answer 20

an interdisciplinary field that applies the principles of engineering and the life science toward the development of biological substitutes that restore, maintain, or improve tissue function

Question 21

22. What is a desmosome and its function?

Answer 21

mechanical attachment of two cells, either in broad bands or is specific spots,

For example Anchoring junctions are a type of desmosome: they transmit stress and are tethered to cytoskeleton filaments inside the cell

Question 22

23. Which soluble signaling is designed for long range signaling?

Answer 22

synaptic long range signaling

Question 23

11. Name three components of the Extra Cellular Matrix

Answer 23

• Collagen
• Elastin
• Fibronectin
• Proteoglycans
• Glycoproteins