Mastering Biology Chapter 6-10

Which of these structures stores, modifies, and packages products?

(A) The Golgi apparatus modifies, stores, and packages products of the ER.

Choose the letter that indicates the organelle that contains most of a cell's DNA.

(C) The nucleus contains most of a cell's DNA.

The structure that regulates the passage of material into and out of this bacterial cell is indicated by the letter

(C) The plasma membrane is selectively permeable.

Which of these provides the cell with structural support?

(D) Microfilaments are a component of the cytoskeleton.

The DNA-containing region of this bacterial cell is indicated by the letter

(D) The nucleoid region contains DNA.

Which of these is the double membrane that encloses the nucleus?

(E) This is the nuclear envelope.

Which of these organelles manufactures proteins bound for secretion out of the cell?

(Rough ER) The ribosomes associated with the rough ER synthesize secretory proteins bound for the exterior of the cell. Further processing and packaging occurs in the Golgi apparatus.

Biologists use the fluid mosaic model to describe membrane structure.

- Because membranes are fluid, membrane proteins and phospholipids can drift about in the membrane. - The framework of a membrane is a bilayer of phospholipids with their hydrophilic heads facing the aqueous environment inside and outside of the cell and their hydrophobic tails clustered in the center. - The diverse proteins found in and attached to membranes perform many important functions. Membranes consist of diverse proteins suspended in and attached to a phospholipid bilayer. Kinks in the unsaturated fatty acid tails of some phospholipids keep the membrane fluid, and a mosaic of proteins perform a variety of functions.

In this diagram of the plasma membranes of two adjoining cells, identify the protein indicated by the white arrow, including its function.

- a receptor protein that binds with a signaling molecule and relays the message into the cell by activating other molecules inside the cell - Signaling proteins are part of signal transduction pathways that transmit external chemical signals into the cell

For each glucose that enters glycolysis, _____ acetyl CoA enter the citric acid cycle.

2

In glycolysis there is a net gain of _____ ATP.

2 It takes 2 ATP to produce 4 ATP.

How many NADH are produced by glycolysis?

2 Two NADH molecules are produced by glycolysis.

In the Calvin cycle, how many ATP molecules are required to regenerate RuBP from five G3P molecules?

3

For each glucose that enters glycolysis, _____ NADH + H+ are produced by the citric acid cycle.

6

How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose?

6

Which of these equations best summarizes photosynthesis?

6 CO2 + 6 H2O → C6H12O6 + 6 O2

What is a function of a bacterium's capsule?

A bacterium's capsule has a protective role.

In cells, what is usually the immediate source of energy for an endergonic reaction?

ATP: The hydrolysis of ATP provides the energy needed for an endergonic reaction.

Which of these enters the citric acid cycle?

Acetyl CoA is a reactant in the citric acid cycle.

Which of these is NOT a product of the citric acid cycle?

Acetyl CoA: Acetyl CoA enters the citric acid cycle.

The _____ is composed of DNA and protein

Chromatin is composed of DNA and protein.

is/are identical in structure to centrioles.

Basal bodies and centrioles have identical structures.

Which of the following statements is TRUE with regard to this animation?

Both sodium and potassium ions are transported against their concentration gradients. Both ions are transported from where their concentration is low to where their concentration is high, and the cell expends energy in the form of ATP to do it.

The reaction ADP + P --> ATP is a(n) _____ reaction.

Endergonic: Energy has been acquired from the surroundings.

As a result of its involvement in a reaction, an enzyme

Enzymes are not changed as a result of their participation in a reaction.

In general, enzymes are what kinds of molecules?

Enzymes are proteins.

Which of these is NOT a product of glycolysis?

FADH2 (It is a product of the citric acid cycle.)

are surface appendages that allow a bacterium to stick to a surface

Fimbriae enable bacterial cells to stick to a surface.

Where is calcium stored?

In addition to storing calcium, the smooth ER also plays a role in detoxification and lipid synthesis.

A(n) _____ reaction occurs spontaneously.

In exergonic reactions the products have less potential energy than the reactants

What is the fate of the phosphate group that is removed when ATP is converted to ADP?

It is acquired by a reactant in an endergonic reaction: By acquiring the phosphate group the reactant acquires energy.

Which of these are hollow rods that shape and support the cell?

Microtubules are rods that also play a role in organelle movement.

Which of these organelles carries out cellular respiration?

Mitochondria convert the chemical energy of organic molecules to chemical energy in the form of ATP.

During electron transport, energy from _____ is used to pump hydrogen ions into the

NADH and FADH2 ... intermembrane space The energy released as electrons, which have been donated by NADH and FADH2, is passed along the electron transport chain and used to pump hydrogen ions into the intermembrane space.

After 3-PGA is phosphorylated, it is reduced by

NADPH supplies the electrons that reduce the phosphorylated 3-PGA.

The final electron acceptor of cellular respiration is

Oxygen is combined with electrons and hydrogen to form water

Which of these organelles produces H2O2 as a by-product?

Peroxisomes produce hydrogen peroxide as a by-product of their metabolic processes.

_____ has a longer wavelength than _____

Red has a longer wavelength than green.

In a bacterium, where are proteins synthesized?

Ribosomes are involved in the manufacture of polypeptides (proteins).

Ribosomal subunits are manufactured by the

Ribosomes are manufactured by the nucleolus.

are the sites of protein synthesis.

Ribosomes are the site of protein synthesis.

Carbon fixation involves the addition of carbon dioxide to

RuBP: In the Calvin cycle, carbon dioxide is added to RuBP.

In glycolysis, what starts the process of glucose oxidation?

Some ATP energy is used to start the process of glucose oxidation.

Where does the Calvin cycle occur?

The Calvin cycle occurs in the stroma

What name is given to the rigid structure, found outside the plasma membrane, that surrounds and supports the bacterial cell?

The cell wall is a rigid supporting structure.

What is the correct label for "A"?

The energy of activation must be overcome in order for a reaction to proceed.

The energy for an endergonic reaction comes from a(n) _____ reaction.

The energy released by an exergonic reaction can be used to drive an endergonic reaction.

The _____ is the bacterial structure that acts as a selective barrier, allowing nutrients to enter the cell and wastes to leave the cell.

The plasma membrane is selectively permeable.

The _____ is a selective barrier, regulating the passage of material into and out of the cell.

The plasma membrane regulates the passage of material into and out of the cell.

endergonic

The products contain more potential energy than the reactants.

Which of these reactions requires a net input of energy from its surroundings?

The products of endergonic reactions have more potential energy than the reactants.

Drag the terms on the left to complete the sentences on the right.

When molecules move down their concentration gradient, they move from where they are more concentrated to where they are less concentrated Diffusion across a biological membrane is called passive transport

In C4 and CAM plants carbon dioxide is fixed in the _____ of mesophyll cells.

cytoplasm: In C4 and CAM plants carbon dioxide fixation occurs in the cytoplasm.

Select the INCORRECT association. 1)kinetic energy-motion 2)exergonic-uphill 3)potential energy-positional energy 4)exergonic-spontaneous 5)enzyme-protein

exergonic-uphill Exergonic reactions release energy.

The following reactionA --> B + C + heatis a(n) _____ reaction.

exergonic: energy has been released

An enzyme

is an organic catalyst: Enzymes are proteins that behave as catalysts.

The proximate (immediate) source of energy for oxidative phosphorylation is

kinetic energy that is released as hydrogen ions diffuse down their concentration gradient

In muscle cells, fermentation produces

lactate and NAD+

Which organelle plays a role in intracellular digestion?

lysosome: the prefix "lyso-" means decomposition.

Where is a bacterial cell's DNA found?

nucleoid region: bacteria lack a nucleus; their DNA is found in the nucleoid region.

In cellular respiration, most ATP molecules are produced by

oxidative phosphorylation This process utilizes energy released by electron transport.

In C3 plants the conservation of water promotes

photorespiration; Conserving water simultaneously reduces the amount of carbon dioxide available to the plant.

In fermentation _____ is reduced and _____ is oxidized.

pyruvate ... NADH: The pyruvate from glycolysis is reduced to either lactate or ethanol, and NADH is oxidized to NAD+.

Enzymes work by

reducing EA: Enzymes work by reducing the energy of activation.

In glycolysis, ATP molecules are produced by

substrate-level phosphorylation (A phosphate group is transferred from glyceraldehyde phosphate to ADP.)

In the citric acid cycle, ATP molecules are produced by

substrate-level phosphorylation: A phosphate group is transferred from GTP to ADP.

What name is given to the reactants in an enzymatically catalyzed reaction?

substrate: This is the name given to the reactants in an enzymatically catalyzed reaction

You are working on a team that is designing a new drug. For this drug to work, it must enter the cytoplasm of specific target cells. Which of the following would be a factor that determines whether the molecule selectively enters the target cells?

the similarity of the drug molecule to other molecules that are transported into the target cells If the target cells have transport proteins that specifically bind to certain molecules, they may bind with and transport a drug that is similar in structure.

What is energy coupling?

the use of energy released from an exergonic reaction to drive an endergonic reaction

C4 plants differ from C3 and CAM plants in that C4 plants

transfer fixed carbon dioxide to cells in which the Calvin cycle occurs: In C3 and CAM plants carbon dioxide fixation and the Calvin cycle occur in the same cells

The light reactions of photosynthesis use _____ and produce

water ... NADPH: NADPH is a reactant in the Calvin cycle