Exam II

Question 1

The cell theory includes the following generalizations about cells:

Answer 1

a. all organisms consist of one or more cells
b. the cell is the smallest unit of life
c. each new cell arises from another cell
d. a cell passes hereditary info to its offspring

Question 2

The surface to volume ratio of a cell:

Answer 2

limits cell size and influences cell shape

Question 3

Cell membranes are characterized mainly by the presence of:

Answer 3

Phopholipid bi-layer

Question 4

Unlike eukaryotic cells, bacterial cells:

Answer 4

have no nucleus

Question 5

Multiple species of single-celled organisms sometimes live together in a mass of slimy polysaccharides that they secrete which is called:

Answer 5

biofilm

Question 6

The function of the nucleus within eukaryotic cells is:

Answer 6

To separate the cell’s DNA from the rest of the cytoplasm and to control the passage of certain molecules bw the nucleus and the cytoplasm

Question 7

I has a double lipid bilayer that surrounds the nucleus, has pores, and is continuous with the membrane of the ER (Endoplasmic Reticulum)

Answer 7

the nuclear envelope

Question 8

The following organelles are components of the endomembrane system:

Answer 8

rough and smooth ER, golgi bodies and lysosomes

Question 9

What differentiates the smooth ER from the rough ER?

Answer 9

the presence of ribosomes which stud the surface of the rough ER

Question 10

This structures are the primary cellular sites for the production of proteins:

Answer 10

ribosomes

Question 11

This organelle, which looks like a stack of pancakes, modifies proteins and lipids then sorts, packages, and ships the finished products to lysosomes or to the plasma membrane:

Answer 11

Golgi body

Question 12

These are common in plants but not animals:

Answer 12

chloroplasts and central vacuoles

Question 13

This contain powerful enzymes and are the main organelles where intracellular digestion/the breakdown of waste products occurs:

Answer 13

lysosomes

Question 14

This organelle is where aerobic respiration occurs, which includes the synthesis of ATP. They are often called the powerhouse of the cell:

Answer 14

mitochondria

Question 15

organelles and plant cells that function in photosynthesis or storage are:

Answer 15

plastids

Question 16

structural features that contain the protein actin and help to strengthen and change the shapes of eukaryotic cells are:

Answer 16

micro-filaments

Question 17

Which junction allows communication bw animal cells?

Answer 17

gap junction

Question 18

In this reaction, reactants have more free energy than the products, ends with a net release of free energy;

Answer 18

exergonic reaction

Question 19

Enzymes increase the rate of a given reaction by lowering what kind of energy?

Answer 19

activation energy

Question 20

Characteristics of enzymes:

Answer 20

control the speed of a reaction, change shape to facilitate certain reactions, may place physical stress on the bonds of the substrate, and may require cofactors

Question 21

Enzymatic reactions can be affected by:

Answer 21

pH, Salinity, temperature, and cofactors

Question 22

In metabolic pathways that are regulated by feedback inhibition, the “product” inhibits the activity of the:

Answer 22

First enzyme

Question 23

Allosteric inhibition of enzymes is generally a result of:

Answer 23

binding regulatory molecules at the allosteric site

Question 24

metabolic pathways in which one molecule accepts electrons from another molecule

Answer 24

redox reaction

Question 25

Organized series of reaction steps in which membranes-bound arrays of enzymes and other molecules give up and accept electrons in turn.

Answer 25

electron transfer chain

Question 26

The rate of diffusion through a semi-permeable membrane are characteristics of;

Answer 26

a. steeper concentration gradients b. higher temperatures c. size of molecule diffusing

Question 27

A cell placed in a hypotonic solution will swell. True or False

Answer 27

True

Question 28

In simple diffusion across a membrane solute moves in which direction?

Answer 28

from an area of high concentration to an area of low concentration

Question 29

The method of movement that requires the expenditure of ATP molecules is:

Answer 29

active transport

Question 30

A red blood cell will swell and burst when placed in what kind of solution?

Answer 30

Hypotonic

Question 31

This molecule needs a transport protein to cross the cell membrane:

Answer 31

glucose

Question 32

What do white blood cells use to capture and destroy foreign particles in the blood?

Answer 32

phagocytosis

Question 33

What is osmosis?

Answer 33

the diffusion of water across a membrane

Question 34

Name two structures single cell organisms use to move through their environments:

Answer 34

flagellum and pseudopod