Chapter 3 Cells

Question 1

What is the function and structure of the peroxisomes?

Answer 1

Function
-house enzymes that catalyze reactions (liver and kidney)
Structure
-membranous sacs

Question 2

What is the function and structure of the microfilaments and microtubules?

Answer 2

Function
-support cytoplasm
-allow movement of organelles
Structure
-thin rods and tubules

Question 3

What is the function and structure of the centrosomes?

Answer 3

Function
-produce cilia and flagella
-distributes chromosomes during cell division
Structure
-Two-rod like centrioles

Question 4

What is the function and the structure of the cilia and the flagellum?

Answer 4

Function
-propels substances on cell surface (cilia)
-provides mobility to sperm
Structure
-short hair-like projections
-long tail-like projections

Question 5

What is diffusion?

Answer 5

Movement of molecules from high to low concentration

Question 6

What is osmosis?

Answer 6

Movement of H2O

Question 7

What is simple diffusion?

Answer 7

Molecules moving freely through the membrane (small nonpolar molecules)

Question 8

What is facilitated diffusion?

Answer 8

Large or charged molecules using protein channels, carriers, or pumps to move down concentration gradient

Question 9

What is passive transport?

Answer 9

-no required energy
-facilitated and simple diffusion
-high to low concentration

Question 10

What is active transport?

Answer 10

-requires energy
-uses protein pump
-low to high concentration

Question 11

What is osmotic pressure?

Answer 11

ability of osmosis to generate enough pressure to move a volume of water

Question 12

Isotonic

Answer 12

no change in mass; same osmotic pressure

Question 13

Hypertonic

Answer 13

mass decreases; higher osmotic pressure

Question 14

Hypotonic

Answer 14

mass increases; lower osmotic pressure

Question 15

What is endocytosis?

Answer 15

occurs when a cell engulfs a substances by forming a vesicle around the substance

Question 16

What is pinocytosis?

Answer 16

substance is mostly water

Question 17

What is phagocytosis?

Answer 17

substance is a soild

Question 18

What is a receptor-mediated endocytosis?

Answer 18

required the substance to bind to a membrane-bound receptor

Question 19

What is exocytosis?

Answer 19

occurs when substances in vesicles fuses with the cell membrane, releasing contents outside the cell

Question 20

What are the three stages of the cell cycle?

Answer 20

-Interphase, mitosis, and cytokinesis

Question 21

What occurs during interphase?

Answer 21

-prepares cell for division
-G0 phase normal function
-G1 phase cell growth
-S phase synthesis of DNA
-G2 phase cell growth
-M phase cell division

Question 22

What occurs during prophase?

Answer 22

-chromosomes form
-nuclear envelope disappears
-centrioles form spindle fibers

Question 23

What occurs during metaphase?

Answer 23

-chromosomes line up at the metaphase plate
-spindle fibers connect to the centromere
-metaphase checkpoint

Question 24

What occurs during anaphase?

Answer 24

-chromosomes move to opposite ends

Question 25

What occurs during telophase?

Answer 25

-nucleus reforms -cleavage furrow forms

Question 26

What is a stem cell?

Answer 26

unspecialized cells that can differentiate into different types of cells with different functions