Ch 4: Cell Structure

Question 1

What is the cell wall/ cell membrane?

Answer 1

The outer layer of a cell

Question 2

What is the cytoplasm or cytosol?

Answer 2

Contains the organelles

Question 3

What is the nucleus?

Answer 3

Bounded by a nuclear membrane, contains chromosomes

Question 4

What organisms has only a cell membrane and not also a cell wall?

Answer 4

Animals

Question 5

What are plant cell walls made up of?

Answer 5

Cellulose (a polysaccharide)

Question 6

What are bacteria cell walls made up of?

Answer 6

Peptidoglycan (protein and sugar)

Question 7

What are fungi cell walls made up of?

Answer 7

Chitin- a polysaccharide similar to cellulose

Question 8

What is the cell membrane made up of?

Answer 8

Lipids and proteins

Question 9

What are the primary lipids found in cell membranes?

Answer 9

Phospholipids (polar and nonpolar regions, form lipid bilayers)

Question 10

Why do cell membranes (made of lipid bilayers) make good barriers?

Answer 10

The inside of the cell is aqueous (water based), as well as the external environment. The lipid bilayer cell membrane forms a fatty layer between them.

Question 11

The cell membrane is _____ permeable.

Answer 11

selectively

Question 12

What is simple diffusion?

Answer 12

Movement of a substance from an area of high concentration to lower concentration until a dynamic equilibrium is reached

Question 13

What is facilitated diffusion?

Answer 13

The molecules that try to cross are hydrophilic, so can’t interact with the oily barrier. So they need help from proteins.

Question 14

What is active transport?

Answer 14

The cell must expend energy to move something across the membrane, can move it from an area of low concentration to one of higher concentration.

Question 15

What is bulk transport?

Answer 15

The movement of large items across the cell membrane, either endocytosis (into the cell) or exocytosis (out of the cell)

Question 16

How does endocytosis work?

Answer 16

The cell takes in a particle by surrounding it within a vesicle.

Question 17

What is osmosis?

Answer 17

The movement of water across a cell membrane (through facilitated diffusion)

Question 18

What is a vacuole?

Answer 18

An organelle that stores waste and other material

Question 19

What are ribosomes?

Answer 19

Sites of protein synthesis; not bound by the membrane

Question 20

What is the smooth endoplasmic reticulum?

Answer 20

System of membrane and tubes that transports substances around the cell

Question 21

What is the rough endoplasmic reticulum?

Answer 21

Endoplasmic reticulum with ribosomes bound to it; ribosomes on the rough ER specifically synthesize membrane proteins or secreted proteins

Question 22

What is the golgi apparatus?

Answer 22

Sorts and packages proteins made by ribosomes on rough ER

Question 23

What is the mitochondria?

Answer 23

Produces ATP for the cell

Question 24

What are lysosomes?

Answer 24

Digest foreign substances and worn-out organelles

Question 25

What are centrioles?

Answer 25

Help to form the spindle during mitosis

Question 26

What is the nucleus?

Answer 26

Control center of the cell; contains DNA

Question 27

What is the nucleolus?

Answer 27

Structure in nucleus, site of ribosome synthesis

Question 28

What is the cell membrane?

Answer 28

Outer membrane that regulates what goes in and out of cell

Question 29

Do animal cells have cell walls?

Answer 29

No

Question 30

What are bacteria cell walls made of?

Answer 30

Peptidoglycan

Question 31

Engulfing large particles in a vesicle is know as:

Answer 31

Endocytosis

Question 32

Facilitated diffusion is a way for _______ substances to cross the cell membrane

Answer 32

Hydrophilic

Question 33

Fungi have cell walls made of ______ and plants have cell walls made of ______.

Answer 33

Chitin, cellulose

Question 34

Does simple diffusion require energy?

Answer 34

No

Question 35

Hydrophobic substances cross the membrane by ________.

Answer 35

Simple diffusion

Question 36

A type of movement that requires energy and moves substances against their concentration gradients is called ______.

Answer 36

Active transport

Question 37

What happens when a cell is placed in a hypertonic (more concentrated) solution?

Answer 37

There are more particles outside, so there is less water outside. Water will move to outside the cell, so it will shrivel up.

Question 38

What happens when a cell is placed in a hypotonic (more dilute) solution?

Answer 38

There are less particles outside, so there is more water inside. Water will move from outside the cell to inside, so the cell will swell up.

Question 39

What happens if a cell is placed in an isotonic (same concentration) solution?

Answer 39

It will neither shrivel nor swell

Question 40

What is a prokaryotic cell?

Answer 40

No organelles

Question 41

The fact that enzymes interact with substrate by physically fitting together has given rise to the phrase “________ and _______”

Answer 41

Lock and key

Question 42

Enzymes are known as organic _______

Answer 42

Catalysts

Question 43

When an enzyme has catalyzed a chemical reaction and the products are formed, is the enzyme itself consumed?

Answer 43

No, it is available to catalyze additional reactions.

Question 44

The location on an enzyme where substrate binds is called the ______.

Answer 44

Active site

Question 45

When an enzyme catalyzes a reaction, is it used up?

Answer 45

No. It is reusable.

Question 46

What are reactants in an enzyme-catalyzed reaction called?

Answer 46

Substrates

Question 47

What type of molecules are enzymes?

Answer 47

Organic (proteins)

Question 48

If enzymes lose their shapes (become denatured) what happens?

Answer 48

They can’t run reactions.

Question 49

What can denature enzymes?

Answer 49

Heat, acids, and bases

Question 50

What are molecules that help enzymes catalyze reactions called?

Answer 50

Coenzymes

Question 51

What act as coenzymes in the body?

Answer 51

Vitamins