Introduction to Cells

Question 1

Outline the cell theory

Answer 1

1. All organisms are made up of one or more cells
2. Cells are the basic unit of organization of organisms
3. All cells come from preexisting cells

Question 2

Define a virus

Answer 2

a non-cellular structure consisting of DNA or RNA surrounded by a protein coat; infects living cells

Question 3

Explain the advantages of a light microscope

Answer 3

1. Color images
2. Larger field of view
3. Easy to prepare samples
4. Observe living material

Question 4

Explain the advantages of an electron microscope

Answer 4

1. Better resolution
2. Higher magnification
3. Ability to view subcellular organelles

Question 5

Define organelle

Answer 5

specialized structure within a cell that has a specific function

Question 6

What is the difference between unicellular and multicellular?

Answer 6

Unicellular: capable of carrying out all functions of life

Multicellular: differentiate to carry specialized functions by expressing only some of their genes

Question 7

Draw and label a prokaryotic cell.

Answer 7

draw :)

Question 8

state functions of prokaryotic cells
(cell wall, pili, flagella, capsule, mesosomes, cytoplasm, plasma membrane, ribosomes, naked DNA

Answer 8

Cell Wall - a rigid structure that helps the bacterium maintain its shape
Pili - attaches cell to surfaces
Flagella: enables movement
Capsule - the outer sticky protective layer
Mesosome - infolding of the plasma membrane to aid in compartmentalization
Cytoplasm - a gel-like liquid that fills the inside of the cell
Plasma membrane - separates the cell from the environment
Nucleoid - a region where naked DNA is found
-Ribosomes- for protein synthesis

Question 9

Draw animal Cell

Answer 9

Draw :)

Question 10

State functions of organelles in eukaryotes
(ribosomes, rough endoplasmic reticulum, lysosomes, Golgi apparatus, mitochondrion, and nucleus)

Answer 10

Ribosomes - site of protein synthesis
Rough Endoplasmic Reticulum - Manufactures proteins and membrane
Lysosomes - Intracellular digestion
Golgi Apparatus - modifies, stores, and routes products of the ER
Mitochondrion - transform energy from the surroundings into usable forms of energy; site for cellular respiration
Nucleus: contains most of the cell’s DNA

Question 10

Description of prokaryotic cells

Answer 10

-do not have a membrane-bound nucleus nor membrane-bound organelles
-small single cells
-very little cellular organization
-single, cellular chromosome of naked DNA
-70s ribosomes

Question 11

Description of eukaryotic cells

Answer 11

-have a membrane-bound nucleus and membrane-bound organelles
-plant cells, animal cells, fungal cells,
-large cells that can exist as a single cell or part of a multicellular organism
-more structure and internal organization
-80s ribosomes

Question 12

What are the stages involved in the cell-division cycle?

Answer 12

Interphase: cell growth and DNA replication
Mitosis: division of cell nucleus; production of two daughter cells
Cytokinesis: division of cytoplasm

Question 13

What are the events that occur during interphase?

Answer 13

G1 phase: cell growth and development
S phase: growth and DNA replication
G2 phase: cell growth and preparation for cell division

Question 14

What occurs during the prophase?

Answer 14

-nucleoli disappears
-chromatins condense into chromosomes that consist of two sister chromatids joined by centromeres
-mitotic spindle forms
-centromeres move apart

Question 15

What occurs during the metaphase?

Answer 15

-sister chromatids align on the metaphase plate in the middle of the cell

Question 16

What occurs during anaphase?

Answer 16

-sister chromatids split apart to separate chromosomes
-kinetochores microtubules shorten
-poles of the cell move farther apart

Question 17

What occurs during telophase?

Answer 17

-nuclear envelopes reform around the chromosomes
-nucleoli reappear
-chromosomes uncoil to chromatins

Question 18

What are the functions of mitosis?

Answer 18

-reproduction: unicellular v. multicellular
-repair: replacement of dead or dying cells
-growth: allows development starting with a fertilized egg

Question 19

List functions of membrane proteins

Answer 19

integral proteins (embedded inside the phospholipid bilayer) -serve as a transporter, carrier, protein channel
peripheral proteins (attached on the surface of bilayer)- helps form shape of membrane

Question 20

List name of six organelles and their functions (animal cell)

Answer 20

1. lysosomes: intercellular digestion and recycling
2. ribosomes: protein synthesis
3. Rough Endoplasmic Reticulum: manufactures proteins and membranes.
4. Golgi Apparatus: modifies, stores & routes products
5. Mitochondria: provides power to the cell
6. Nucleus: contains most of the cell’s DNA

Question 21

List the names of eight organelles and their functions (prokaryotic cell)

Answer 21

1. Pili: attaches cell to surfaces
2. Flagellum: enables movement
3. naked DNA
4. Cytoplasm
5. Ribosome: protein synthesis
6. Mesosome
7. cell wall
8. plasma membrane