4.1

Question 1

Characterize the structural similarities of all cells (i.e., the common features).

Answer 1

All cells have: a(n enclosing) plasma membrane, (semifluid) cytoplasm, chromosomes (centrally located DNA material) and ribosomes

Question 2

Describe the role of the plasma membrane in all cells.

Answer 2

The plasma membrane is a selectively permeable barrier that allows oxygen, nutrients and waste in and out of the cell

Question 3

Define the function of cytoplasm

Answer 3

The fluid that fills the inside of the cell. Its like the medium or “host” for chemical reaction that happen in the cell

Question 4

Describe the organization of prokaryotic cells.

Answer 4

1. No membrane bound organelles
2. DNA is in Nucleoid region
3. cytoplasm

Question 5

Discuss the cell theory. (a unifying foundation of cell biology)

Answer 5

1. all organisms are composed of one or more cells, and the life processes of metabolism and heredity occur within these cells
2. cells are the smallest living things, the basic units of organization of all organisms
3. cells arise only by division of a previously existing cell

Question 6

Describe the factors that limit cell size.

Answer 6

Diffusion of substances into and out of cells
 As cell size increases, diffusion becomes inefficient

Question 7

Describe the advantage of a relatively small cell size.

Answer 7

A smaller cell has a better surface area-to-volume ratio so diffusion is most efficient.

Question 8

Differentiate the types of microscopy.

Answer 8

• Light microscopy
-lowest magnification
• scanning electron microscopy
• transmission electron microscopy
-highest magnification

Question 9

Define the function of ribosomes

Answer 9

Protein synthesis

Question 10

Define the function of chromosomes

Answer 10

Genetic information necessary for the function of the cell

Question 11

compare the organization of prokaryotic and eukaryotic

Answer 11

1. Prokaryotic cells:
    No nucleus- DNA in an unbound region called the nucleiod
    No membrane bound organelles
    Cytoplasm is bound by plasma membrane
    Has ribosomes
2. Eukaryotic Cells:
    DNA in Nucleus bound by a membranous nuclear envelope
    Membrane bound organelles
    Cytoplasm between plasma membrane and nucleus
    Generally larger that prokaryotic cells