A drug designed to inhibit the response of cells to testosterone would almost certainly result in which of the following?

A drug designed to inhibit the response of cells to testosterone would almost certainly result in which of the following? A) lower cytoplasmic levels...

Caffeine is an inhibitor of phosphodiesterase. Therefore, the cells of a person who has recently consumed coffee would have increased levels of

Caffeine is an inhibitor of phosphodiesterase. Therefore, the cells of a person who has recently consumed coffee would have increased levels of A)...

Which of the following is not true of cell communication systems?

Which of the following is not true of cell communication systems? A) Cell signaling was an early event in the evolution of life. B) Communicating...

The general name for an enzyme that transfers phosphate groups from ATP to a protein is

The general name for an enzyme that transfers phosphate groups from ATP to a protein is A) phosphorylase. B) phosphatase. C) protein kinase. D) ATPase. E)...

Which of the following is a widely used second messenger in signal transduction pathways?

Which of the following is a widely used second messenger in signal transduction pathways? A) calcium ions B) cyclic AMP C) inositol trisphosphate D)...

Which of the following is (are) true regarding the activity of a protein regulated by phosphorylation?

Which of the following is (are) true regarding the activity of a protein regulated by phosphorylation? A) It depends mostly on the concentration...

In general, a signal transmitted via phosphorylation of a series of proteins

In general, a signal transmitted via phosphorylation of a series of proteins A) brings a conformational change to each protein. B) requires binding...

The receptors for a group of signaling molecules known as growth factors are often

The receptors for a group of signaling molecules known as growth factors are often A) ligand-gated ion channels. B) G-protein-linked receptors. C)...

Testosterone functions inside a cell by

Testosterone functions inside a cell by A) acting as a signal receptor that activates ion-channel proteins. B) binding with a receptor protein that...

Which of the following are chemical messengers that pass through the plasma membrane of cells and have receptor molecules in the cytoplasm?

Which of the following are chemical messengers that pass through the plasma membrane of cells and have receptor molecules in the cytoplasm? A) insulin B)...

Up to 60% of all medicines used today exert their effects by influencing what structures in the cell membrane?

Up to 60% of all medicines used today exert their effects by influencing what structures in the cell membrane? A) tyrosine-kinases receptors B) ligand-gated...

G proteins and G-protein-linked receptors

G proteins and G-protein-linked receptors A) are found only in animal cells. B) are found only in bacterial cells. C) are thought to have evolved...

What would be true for the signaling system in an animal cell that lacks the ability to produce GTP?

What would be true for the signaling system in an animal cell that lacks the ability to produce GTP? A) It would not be able to activate and inactivate...

Which of the following signal systems use(s) G-protein-linked receptors?

Which of the following signal systems use(s) G-protein-linked receptors? A) yeast mating factors B) epinephrine C) neurotransmitters D) A and C only E)...

Most signal molecules

Most signal molecules A) bind to specific sites on receptor proteins in a membrane. B) are water-soluble. C) are able to pass through the plasma...

Which of the following is (are) true of ligand-gated ion channels?

Which of the following is (are) true of ligand-gated ion channels? A) They are important in the nervous system. B) They lead to changes in sodium...

A small molecule that specifically binds to another molecule, usually a larger one

A small molecule that specifically binds to another molecule, usually a larger one A) is called a signal transducer. B) is called a ligand. C) is...

The signal transduction pathway in animal cells which is initiated by epinephrine

The signal transduction pathway in animal cells which is initiated by epinephrine A) activates the breakdown of glycogen in liver and skeletal muscle...

The process of transduction usually begins

The process of transduction usually begins A) when the chemical signal is released from the alpha cell. B) when the signal molecule changes the receptor...

From the perspective of the cell receiving the message, the three stages of cell signaling are

From the perspective of the cell receiving the message, the three stages of cell signaling are A) the paracrine, local, and synaptic stages. B) signal...

The old saying "one rotten apple spoils the whole barrel" is due to chemical signaling in plants via

The old saying "one rotten apple spoils the whole barrel" is due to chemical signaling in plants via A) an increased uptake of carbon dioxide during...

Which of the following is true of synaptic signaling and hormonal signaling?

Which of the following is true of synaptic signaling and hormonal signaling? A) Hormonal signaling occurs in animals only. B) Hormonal signaling...

What could happen to the target cells that lack receptor proteins for ligands from local regulators?

What could happen to the target cells that lack receptor proteins for ligands from local regulators? A) They could compensate by receiving nutrients...

Which of the following does not occur during the Calvin cycle?

Which of the following does not occur during the Calvin cycle? A) carbon fixation B) oxidation of NADPH C) release of oxygen D) regeneration of the...

Carbon fixation involves the addition of carbon dioxide to

Carbon fixation involves the addition of carbon dioxide to A) rubisco. B) RuBP. C) G3P. D) 3-PGA. E) NADPH. Answer: ...

Of the following, what do both mitochondria and chloroplasts have in common?

Of the following, what do both mitochondria and chloroplasts have in common? A) thylakoid membranes B) chemiosmosis C) ATP synthase D) B and C only E)...

Where is the electron transport chain found in plant cells?

Where is the electron transport chain found in plant cells? A) thylakoid membranes of chloroplasts B) stroma of chloroplasts C) inner membrane of...

Which of the following statements best describes the relationship between photosynthesis and respiration?

Which of the following statements best describes the relationship between photosynthesis and respiration? A) Respiration is the reversal of the biochemical...

Which of the following is (are) required in the Calvin cycle?

Which of the following is (are) required in the Calvin cycle? A) CO2 B) ATP C) RuBP D) A and B only E) A, B, and C Answer: ...

Where do the enzymatic reactions of the Calvin cycle take place?

Where do the enzymatic reactions of the Calvin cycle take place? A) stroma of the chloroplast B) thylakoid membranes C) outer membrane of the chloroplast D)...

In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons from

In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates...

Suppose the interior of the thylakoids of isolated chloroplasts were made acidic and then transferred in the dark to a pH-8 solution. What would be likely to happen?

Suppose the interior of the thylakoids of isolated chloroplasts were made acidic and then transferred in the dark to a pH-8 solution. What would be...

As a research scientist, you measure the amount of ATP and NADPH consumed by the Calvin cycle in 1 hour. You find 30,000 molecules of ATP consumed, but only 20,000 molecules of NADPH. Where did the extra ATP molecules come from?

As a research scientist, you measure the amount of ATP and NADPH consumed by the Calvin cycle in 1 hour. You find 30,000 molecules of ATP consumed,...

What does cyclic electron flow in the chloroplast produce?

What does cyclic electron flow in the chloroplast produce? A) ATP B) NADPH C) glucose D) A and B E) A, B, and C Answer: ...

What are the products of noncyclic photophosphorylation?

What are the products of noncyclic photophosphorylation? A) heat and fluorescence B) ATP and P700 C) ATP and NADPH D) ADP and NADP E) P700 and P6...

Which of the following statements about the light reactions of photosynthesis are true?

Which of the following statements about the light reactions of photosynthesis are true? A) The splitting of water molecules provides a source of electrons. B)...

An outcome of this experiment was to help determine

Theodor W. Engelmann illuminated a filament of algae with light that passed through a prism, thus exposing different segments of algae to different wavelengths...

What did Engelmann conclude about the congregation of bacteria in the red and blue areas?

Theodor W. Engelmann illuminated a filament of algae with light that passed through a prism, thus exposing different segments of algae to different wavelengths...

During photosynthesis, visible light has enough energy to

During photosynthesis, visible light has enough energy to A) force electrons closer to the nucleus. B) excite electrons. C) split a water molecule...

All of the events listed below occur in the light reactions of photosynthesis except

All of the events listed below occur in the light reactions of photosynthesis except A) oxygen is produced. B) NADP+ is reduced to NADPH. C) carbon...

A plant has a unique photosynthetic pigment. The leaves of this plant appear to be reddish yellow. What wavelengths of visible light are not being absorbed by this pigment?

A plant has a unique photosynthetic pigment. The leaves of this plant appear to be reddish yellow. What wavelengths of visible light are not being absorbed...

Where does the Calvin cycle take place?

Where does the Calvin cycle take place? A) stroma of the chloroplast B) thylakoid membrane C) cytoplasm surrounding the chloroplast D) chlorophyll...

What are the products of the light reactions that are subsequently used by the Calvin cycle?

What are the products of the light reactions that are subsequently used by the Calvin cycle? A) oxygen and carbon dioxide B) carbon dioxide and RuBP C)...

If photosynthesizing green algae are provided with CO2 synthesized with heavy oxygen (18O), later analysis will show that all but one of the following compounds produced by the algae contain the 18O label. That one exception is

If photosynthesizing green algae are provided with CO2 synthesized with heavy oxygen (18O), later analysis will show that all but one of the following...

If photosynthesizing green algae are provided with CO2 synthesized with heavy oxygen (18O), later analysis will show that all but one of the following compounds produced by the algae contain the 18O label. That one exception is

If photosynthesizing green algae are provided with CO2 synthesized with heavy oxygen (18O), later analysis will show that all but one of the following...

The early suggestion that the oxygen (O2) liberated from plants during photosynthesis comes from water was

The early suggestion that the oxygen (O2) liberated from plants during photosynthesis comes from water was A) first proposed by C.B. van Niel of...

Which type of organism obtains energy by metabolizing molecules produced by other organisms?

Which type of organism obtains energy by metabolizing molecules produced by other organisms? A) autotrophs B) heterotrophs C) decomposers D) B and...

Organisms that can exist with light as an energy source and an inorganic form of carbon and other raw materials

Organisms that can exist with light as an energy source and an inorganic form of carbon and other raw materials A) are called photoautotrophs. B)...

What happens at the end of the chain in Figure 7.2?

What happens at the end of the chain in Figure 7.2?  A) Two electrons combine with a molecule of oxygen and two hydrogen atoms. B) Two electrons...

A young dog has never had much energy. He is brought to a veterinarian for help and she decides to conduct several diagnostic tests. She discovers that the dog's mitochondria can use only fatty acids and amino acids for respiration, and his cells produce more lactate than normal. Of the following, which is the best explanation of the dog's condition?

A young dog has never had much energy. He is brought to a veterinarian for help and she decides to conduct several diagnostic tests. She discovers that...