exam 5 (chapter 6,7)

Question 1

• Maintains essential differences between intracellular and extracellular environment
• Phospholipid bilayer and proteins
• Together, the lipid bilayer and proteins are semi-permeable

Answer 1

Plasma Membrane

Question 2

Impermeable to water soluble molecules, fluid and soft

Answer 2

Phospholipid Bilayer

Question 3

• Mediate passage of water-soluble molecules
• Some function as enzymes
• Some function as signal transducers
• Control interactions between cells of a multicellular organism

Answer 3

Proteins

Question 4

-Proteins may move laterally (they do not flip-flop)
-Hypothesis: Proteins from 2 different cells will mix
-Experiment: Combine mouse cell and a human cell and follow the protein ‘markers’
Results: Proteins mixed

Answer 4

Fluid-Mosaic Model

Question 5

Fluidity of phospholipid membrane depends on what 2 things?

Answer 5

Temperature, phospholipid composition

Question 6

a. Transport
b. Enzymatic activity
c. Signal transduction
d. Cell-Cell Recognition
e. Intercellular joining
f. Attachment of cytoskeleton and extracellular matrix (ECM)

Answer 6

Functions of Membrane Proteins

Question 7

Undergo conformation change

Answer 7

Carriers

Question 8

Form pores across membrane, solutes pass quickly when pores are open

Answer 8

Channels

Question 9

Movement of molecules down their concentration gradient

Answer 9

Simple Diffusion

Question 10

Diffusion of water (occurs directly through the membrane or via protein channels called aquaporins)

Answer 10

Osmosis

Question 11

Move concentration gradients across the membrane

• Na+-K+ ATPase (sodium potassium pump)
• H+ pumps (proton pump)

Answer 11

Ion Pumps

Question 12

Transport out of a cell

Answer 12

Exocytosis

Question 13

Transport into a cell

Answer 13

Endocytosis

Question 14

A liquid that is a homogeneous mixture of 2 or more substances

Answer 14

Solution

Question 15

The dissolving agent or the liquid in greatest abundance in the solution (example: water)

Answer 15

Solvent

Question 16

The substance being dissolved

Answer 16

Solute

Question 17

Water moves out of the cell

-The surrounding solution has greater amount of solutes

Answer 17

Hypertonic Solution

Question 18

Water moves into the cell

-The surround solution has a lower amount of solutes

Answer 18

Hypotonic Solution

Question 19

There is no movement of water

-The surrounding solution has an equal concentration of solutes compared to the inside of the cell

Answer 19

Isotonic Solution

Question 20

The smallest structure alive

• Regulate their internal environment
• Gives rise to new ones
• Produce movement
• Take in energy and release waste products

Answer 20

Cell

Question 21

Regulates flow of molecules into and out of the cell, surrounds all cells

Answer 21

Plasma Membrane

Question 22

Fluid inside cell

Answer 22

Cytosol

Question 23

Protein synthesis

Answer 23

Ribosomes

Question 24

Has a unique set of chemicals (pH, enzymes, other proteins), different metabolic function

Answer 24

Organelles

Question 25

- Contains genetic material (DNA) - Components: 1. nucleolus 2. nuclear membrane 3. chromatin

Answer 25

Nucleus

Question 26

Site of ribosome production

Answer 26

Nucleolus

Question 27

The complex and DNA and associated proteins

Answer 27

Chromatin

Question 28

When a cell gets ready to divide, the chromatin coils tightly

Answer 28

Chromosome

Question 29

Covered with ribosomes, functions in protein synthesis

Answer 29

Rough ER

Question 30

Functions in lipid metabolism, synthesis of cholesterol and steroid hormones

Answer 30

Smooth ER

Question 31

Vesicles transport proteins to golgi

Answer 31

Transitional ER

Question 32

- Modifies proteins and lipids from ER - Sorts proteins and lipids for final destinations - Packages and exports proteins and lipids in vesicles - In plant cells, manufactures polysaccharides

Answer 32

Golgi Apparatus

Question 33

- Controlled intracellular digestion of macromolecules - pH=5 - Only found in animal cells

Answer 33

Lysosomes

Question 34

Stores water, only found in plant cells

Answer 34

Vacuole

Question 35

- Energy factories - Site of cellular respiration (turns glucose into ATP) - Number in a cell correlates with cell's energy demand - Has its own DNA - Found in plant and animal cells - Maternally inherited in humans

Answer 35

Mitochondria

Question 36

Evolutionary origins of mitochondria and chloroplasts Evidence: -Own genome ribosomes -2 membranes -Arise only by growth and division of existing mitochondria or chloroplasts -Division not timed with nuclear division

Answer 36

Endosymbiont Theory

Question 37

Some ?? have specialized membranes that perform metabolic functions -Are usually unfolding of the plasma membrane

Answer 37

prokaryotes

Question 38

= colored form Example: orange of carrots, red of tomatoes, red of peppers Can see when chlorophyll exits the leaves of trees in fall

Answer 38

Chromoplast

Question 39

=green form

Answer 39

Chloroplast

Question 40

=white form | example: holds starch in potatoes

Answer 40

Leucoplast

Question 41

- Produces hydrogen peroxide as a biproduct - Breaks down fatty acids, alcohol - Found in plant and animal cells

Answer 41

Peroxisome

Question 42

Cytoplasmic streaming, cell division (cleavage furrow formation)

Answer 42

Microfilaments

Question 43

Maintenance of cell shape (tension-bearing elements), anchorage of nucleus and certain other organelles

Answer 43

Intermediate Filaments

Question 44

Chromosome movements in cell division, cell motility (as in cilia or flagella), organelle movement

Answer 44

Microtubules

Question 45

Located in the centrosome, only in animal cells, microtubule-organizing center -When the cell divides, fibers help move the chromosomes into the new cells

Answer 45

Centrioles

Question 46

1. Protects the cells 2. Provides shape 3. Prevents uptake of excess water 4. Holds the plant up against gravity - Composed of cellulose - Some protists, fungi, and prokaryotes also have them of different construction - Only found in plant cells

Answer 46

Cell Wall

Question 47

Connect the cytosol of adjacent cells

Answer 47

Plasmodesmata

Question 48

Make a waterproof seal Example: skin, intestines Only in animal cells

Answer 48

Tight Junctions

Question 49

Forms tissues, only in animal cells

Answer 49

Desmosome

Question 50

Similar to plasmodesmata in plants (communication between cells), only in animal cells

Answer 50

Gap Junctions

Question 51

What is structure is found in all cells?

Answer 51

ribosomes

Question 52

Flow of lipids and membranes - Nuclear envelope - ER - golgi - lysosomes - vesicles - vacuoles

Answer 52

Endomembrane System

Question 53

- Regulation of water inside a cell - Organsims that live in a hypertonic or hypotonic environment must have ways to control solute concentrations and water balance - Contractile vacuoles moves water out of cell

Answer 53

Osmoregulation

Question 54

Description of cell structure and function?

Answer 54

Plant and animal cells carry out cellular respiration, producing ATP

Question 55

Fluid or air-filled cavity or sac

Answer 55

Vesicle

Question 56

The movement of a substance from high to low concentration

Answer 56

Diffusion

Question 57

The movement of a substance across a cell membrane against its concentration gradient

Answer 57

Active Transport

Question 58

The diffusion of a substance across a biological membrane with no expenditure of energy

Answer 58

Passive Transport

Question 59

The ability of a surrounding solution to cause a cell to gain or lose water

Answer 59

Tonicity