Chapter 3 CELL STRUCTURE AND FUNCTION

Question 1

What does the cell theory tell us?

Answer 1

• A cell is the basic unit of life.
• All living things are made up of cells.
• New cells arise from pre-existing cells.

Question 2

Compound light microscope

Answer 2

– Lower magnification

– Uses light beams to view images – Can view live specimens

Question 3

Transmission electron microscope

Answer 3

– 2-D image

– Uses electrons to view internal structure – High magnification, no live specimens

Question 4

Scanning electron microscope

Answer 4

– 3-D image

– Uses electrons to view surface structures – High magnification, no live specimens

Question 5

Prokaryotic cells

Answer 5

– Lack a nucleus

– Represented by bacteria and archaea

Question 6

Eukaryotic cells

Answer 6

– Have a nucleus that houses DNA – Many membrane-bound organelles

Question 7

plasma membrane

Answer 7

surrounds and delineates the cell

Question 8

cytoplasm

Answer 8

the semi-fluid substance inside the cell that contains organelles

Question 9

What are some characteristics of the plasma membrane? 5

Answer 9

• It is a phospholipid bilayer.
• It is embedded with proteins that move in space. • It contains cholesterol for support.
• It contains carbohydrates on proteins and lipids.
• It is selectively permeable.

Question 10

How do things move across the plasma membrane? 5

Answer 10

1. Diffusion
2. Osmosis
3. Facilitated transport
4. Active transport
5. Endocytosis and exocytosis

Question 11

Diffusion

Answer 11

random movement of molecules from a higher concentration to a lower concentration.

Question 12

Osmosis

Answer 12

is the diffusion of water molecules.

Question 13

Isotonic

Answer 13

solutions have equal amounts of solute inside and outside the cell and thus do not affect the cell.

Question 14

Hypotonic

Answer 14

solutions have less solute than the inside of the cell and lead to bursting.

Question 15

Hypertonic

Answer 15

solutions have more solute than the inside
of the cell and lead to shriveling.
H2

Question 16

Facilitated transport

Answer 16

is the transport of molecules across the plasma membrane from higher concentration to lower concentration via a protein carrier.

Question 17

Active transport

Answer 17

is the movement of molecules from a lower to higher concentration using ATP as energy; it requires a protein carrier.

Question 18

What is the structure and function of the nucleus? 3

Answer 18

Bound by a porous nuclear envelope
•
• Houses chromatin: DNA with associated proteins
• Nucleolus contains ribosomal RNA (rRNA)

Question 19

What is the structure and function of ribosomes? 3

Answer 19

• Organelles made of rRNA and protein
• Found bound to the endoplasmic reticulum and free floating in the cytoplasm
• Sites of protein synthesis

Question 20

What is the endomembrane system? 2

Answer 20

• It is a series of membranes in which molecules are transported in the cell.
• It consists of the nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, and vesicles.

Question 21

Rough endoplasmic reticulum

Answer 21

studded with ribosomes used to make proteins

Question 22

Smooth endoplasmic reticulum

Answer 22

lacks ribosomes but aids in making carbohydrates and lipids

Question 23

Golgi apparatus

Answer 23

flattened stacks that process, package, and deliver proteins and lipids from the ER

Question 24

Lysosomes

Answer 24

membranous vesicles made by the Golgi that contain digestive enzymes

Question 25

Vesicles

Answer 25

small membranous sacs used for transport

Question 26

cytoskeleton

Answer 26

A series of proteins that maintain cell shape, as well as anchors and/or moves organelles in the cell

Question 27

What are cilia and flagella?

Answer 27

Both are used in movement.

Question 28

mitochondria

Answer 28

Produce energy in the form of ATP

Question 29

What is cellular respiration?

Answer 29

• Production of ATP in a cell
• Includes
1. Glycolysis
2. Citric acid cycle (Krebs cycle) 3. Electron transport chain

Question 30

GLYCOLYSIS 4

Answer 30

• Occurs in the cytoplasm
• Breaks glucose into 2 pyruvate
• NADH and 2 ATP molecules are made • Does not require oxygen

Question 31

Citric acid cycle (Krebs cycle) 4

Answer 31

– A cyclical pathway that occurs in the mitochondria

– Produces NADH and 2 ATP – Releases carbon dioxide

Question 32

Electron transport chain

Answer 32

Series of molecules embedded in the mitochondrial membrane