Bio CH.4, 5, 6 Cell Structures

. Describe the connection between anabolic and catabolic chemical reactions in a metabolic pathway. Catabolic reactions produce energy and simpler compounds, whereas anabolic reactions involve the use of energy to make more complex compounds. Catabolic reactions produce energy and complex compounds are formed, whereas in anabolic reactions free energy is utilized by complex compounds to make simpler molecules. Catabolic reactions utilize energy and gives simpler compounds, whereas in anabolic reactions, energy is produced and simpler compounds are used to make complex molecules. Catabolic reactions produce energy and water molecules, whereas in anabolic reactions this free energy is utilized by simpler compounds to make only proteins and nucleic acids.

Catabolic reactions produce energy and simpler compounds, whereas anabolic reactions involve the use of energy to make more complex compounds.

Which statement provides the most accurate evidence to support the claim that chemical reactions play a role in energy transfer? Energy from the breakdown of glucose and other molecules in animals is released as ATP, which transfers energy to other reactions. Energy from the breakdown of glucose and other molecules in animals is released in the form of NADP, which transfers energy to other reactions. Energy is released in the form of glucose from the breakdown of ATP molecules. These ATP molecules transfer energy from one reaction to other reactions. Energy is released in the form of water and oxygen from the breakdown of glucose. These molecules transfer energy from one reaction to other reactions.

Energy from the breakdown of glucose and other molecules in animals is released as ATP, which transfers energy to other reactions.

How does enzyme feedback inhibition benefit a cell? Feedback inhibition benefits the cell by blocking the production of the products by changing the configuration of enzymes. This will prevent the cells from becoming toxic. Feedback inhibition benefits the cell by blocking the production of the reactants by changing the configuration of enzymes. This will prevent the cells from becoming toxic. Feedback inhibition benefits the cell by blocking the production of the products by changing the configuration of reactants. This will prevent the cells from becoming toxic. Feedback inhibition benefits the cell by blocking the production of the products by reducing the reactants. This will prevent the cells from becoming toxic.

Feedback inhibition benefits the cell by blocking the production of the products by changing the configuration of enzymes. This will prevent the cells from becoming toxic.

.The fluid mosaic model described the plasma membrane, seen here, as a mosaic of components. Why is it advantageous for the plasma membrane to be fluid in nature? Fluidity allows greater flexibility to the cell and motion of membrane components required for transport. Fluidity helps only in transport of some materials, and does not contribute to the flexibility. Fluidity helps in maintaining the pH of intracellular fluid, and helps in maintaining the physiological pH of the cell. Fluidity helps in providing mechanical strength to the plasma membrane.

Fluidity allows greater flexibility to the cell and motion of membrane components required for transport.

. How would an organism maintain membrane fluidity in an environment where temperatures fluctuated from very high to very low? Greater proportion of unsaturated phospholipids in membranes. Greater proportion of saturated phospholipids in membranes. Greater proportion of carbohydrates in membranes. Greater proportion of proteins in membranes.

Greater proportion of unsaturated phospholipids in membranes.

Why is ATP considered the energy currency of the cell? It accepts energy from chemical reactions. It holds energy at the site of release from substrates. It is a protein. It can transport energy to locations within the cell.

It can transport energy to locations within the cell.

Mitochondria are observed in plant cells that contain chloroplasts. Why do you find mitochondria in photosynthetic tissue? Mitochondria are not needed but are an evolutionary relic. Mitochondria and chloroplasts work together to use light energy to make sugars. Mitochondria participate in the Calvin cycle/light independent reactions of photosynthesis. Mitochondria are required to break down sugars and other materials for energy.

Mitochondria are required to break down sugars and other materials for energy.

Eukaryotic cells contain complex organelles that carry out their chemical reactions. While prokaryotes lack many of these complex organelles, they have a variety of unique structures of their own. Most prokaryotic cells can, however, exchange nutrients with the outside environment faster than most eukaryotic cells. Why is this so? Most prokaryotic cells are smaller and have a higher surface area-to-volume ratio than eukaryotic cells. Most prokaryotic cells are larger and have a higher surface area-to-volume ratio than eukaryotic cells. Most prokaryotic cells are smaller and have a lower surface area-to-volume ratio than eukaryotic cells. Most prokaryotic cells are larger and have a lower surface area-to-volume ratio than eukaryotic cells.

Most prokaryotic cells are smaller and have a higher surface area-to-volume ratio than eukaryotic cells.

Which of the following observations contributed to cell theory? Animal and plant cells have nuclei and organelles. Non-living material cannot give rise to living organisms. Prokaryotic and eukaryotic cells are surrounded by a plasma membrane. Viruses replicate.

Non-living material cannot give rise to living organisms.

Enzymes facilitate chemical reactions that result in changes to a substrate. Support this claim with an example by answering this question: How does the induced fit model of enzymes and substrates explain their function? Both enzyme and substrate undergo dynamic changes, inducing the transition state of the substrate. The enzyme induces a change in the substrate but is not changed itself during the reaction. The substrates attach to the enzyme and the chemical reaction proceeds. The enzyme changes shape to fit the substrate causing the transition state to occur.

The enzyme induces a change in the substrate but is not changed itself during the reaction.

Is the nuclear membrane part of the endomembrane system? Why or why not? The nuclear membrane is not a part of the endomembrane system as the endoplasmic reticulum is a separate organelle of the cell. The nuclear membrane is considered a part of the endomembrane system as it is continuous with the Golgi body. The nuclear membrane is part of the endomembrane system as it is continuous with the rough endoplasmic reticulum. The nuclear membrane is not considered a part of the endomembrane system as the nucleus is a separate organelle.

The nuclear membrane is part of the endomembrane system as it is continuous with the rough endoplasmic reticulum.

In addition to a plasma membrane, a eukaryotic cell has organelles, such as mitochondria, that also have membranes. In which way would these membranes differ? The proportion of phosphate within the phospholipids will vary. Only certain membranes contain phospholipids. Only certain membranes are selectively permeable. The proportions of proteins, lipids, and carbohydrates will vary.

The proportions of proteins, lipids, and carbohydrates will vary.

What happens to the proteins that are synthesized on free ribosomes in the cytoplasm? Do they go through the Golgi apparatus? These proteins move through the Golgi apparatus and enter in the nucleus. These proteins go through the Golgi apparatus and remain in the cytosol. The proteins do not go through the Golgi apparatus and move into the nucleus for processing. The proteins do not go through the Golgi apparatus and remain free in the cytosol.

The proteins do not go through the Golgi apparatus and remain free in the cytosol.

What happens if an enzyme is not functioning in a chemical reaction in a living organism that needs it? The reaction stops. The reaction proceeds, but much more slowly. The reaction proceeds faster without the interference. There is no change in the reaction rate.

The reaction proceeds, but much more slowly.

Describe the position of the transition state on a vertical energy scale, from low to high, relative to the position of the reactants and products, for both endergonic and exergonic reactions. The transition state of the reaction exists at a lower energy level than the reactants. Activation energy is always positive regardless of whether the reaction is exergonic or endergonic. The transition state of the reaction exists at a higher energy level than the reactants. Activation energy is always positive regardless of whether the reaction is exergonic or endergonic. The transition state of the reaction exists at a lower energy level than the reactants. Activation energy is always negative regardless of whether the reaction is exergonic or endergonic. The transition state of the reaction exists at an intermediate energy level than that of the reactants. Activation energy is always positive regardless of whether the reaction is exergonic or endergonic.

The transition state of the reaction exists at a higher energy level than the reactants. Activation energy is always positive regardless of whether the reaction is exergonic or endergonic.

Which of the following is not true about enzymes? They increase the free energy of reactions. They are usually made of amino acids. They lower the activation energy of chemical reactions. Each one is specific to the particular substrate, or substrates, to which it binds.

They increase the free energy of reactions.

Which of the following is most likely to have the greatest concentration of smooth endoplasmic reticulum (SER)? a cell that secretes enzymes a cell that destroys pathogens a cell that makes steroid hormones a cell that engages in photosynthesis

a cell that makes steroid hormones

Energy can be taken in as glucose, then has to be converted to a form that can be easily used to perform work in cells. What is the name of the latter molecule? anabolic molecules cholesterol electrolytes adenosine triphosphate

adenosine triphosphate

An allosteric inhibitor does which of the following? binds to an enzyme away from the active site and changes the conformation of the active site, increasing its affinity for substrate binding binds to an active site and blocks it from binding substrate binds to an enzyme away from the active site and changes the conformation of the active site, decreasing its affinity for the substrate binds directly to the active site and mimics the substrate

binds to an enzyme away from the active site and changes the conformation of the active site, decreasing its affinity for the substrate

It has been accepted that life on the Earth started out as single celled, simple organisms, which then evolved into complex organisms. How did evolution proceed to produce such a wide variety of living organisms from a simple ancestor? Prokaryotes produced the fungi, then the protists which then branches to plants and animals. Protists evolved first, then the prokaryotes, which branched into the fungi, plants, and animals Prokaryotes produced the protists, which branched into the fungi, plants, and animals. Prokaryotes produced the protists, then the fungi, which branched into the plants and animals.

c. Prokaryotes produced the protists, which branched into the fungi, plants, and animals.

What is the basic unit of life? cell organism organ tissue

cell

. Which of the following structures is not found in prokaryotic cells? plasma membrane chloroplast nucleoid ribosome

chloroplast

Which characteristic of a phospholipid, shown here, increases the fluidity of the membrane? cholesterol its head saturated fatty acid tail unsaturated fatty acid tail

cholesterol

. Enzyme inhibitors play an important part in the control of enzyme functions, allowing them to continue, or inhibiting them for a period of time. Which inhibitor affects the initial rate but do not affect the maximal rate? allosteric competitive non-competitive uncompetitive

competitive

. Identify the principal driving movement in diffusion, such as depicted here. concentration gradient membrane surface area particle size temperature

concentration gradient

What process is used by prokaryotes to obtain some materials and remove waste? cell division diffusion flagellar motion ribosomes

diffusion

Which of the following is a catabolic process? digestion of sucrose dissolving sugar in water DNA replication RNA translation

digestion of sucrose

Water moves via osmosis across plasma cell membranes in which direction? from an area with a high concentration of other solutes to a lower one from an area with a high concentration of water to one of lower concentration from an area with a low concentration of water to one of higher concentration. throughout the cytoplasm

from an area with a high concentration of water to one of lower concentration

Where would you find DNA, the genetic material, in an animal cell? in the centriole only in the mitochondria in the mitochondria and the nucleus

in the mitochondria and the nucleus

Which of the following produces the energy needed for protein synthesis in the endomembrane system? endoplasmic reticulum Golgi apparatus lysosome mitochondrion

mitochondrion

If protein synthesis on the ribosome is interrupted, what is the next step that cannot occur? modification in the Golgi apparatus distribution in the endoplasmic reticulum modification in the endoplasmic reticulum distribution via the Golgi apparatus

modification in the endoplasmic reticulum

. Which of the following is surrounded by two phospholipid bilayers? lysosomes ribosomes nucleolus nucleus

nucleolus

In plant cells, the function of the lysosomes is carried out by what? nuclei peroxisomes ribosomes vacuole

peroxisomes

. Which of the following is found both in eukaryotic and prokaryotic cells? mitochondrion nucleus ribosomes centrosomes

ribosomes

1. When viewing a specimen through a light microscope, what is a method that scientists use to make it easier to see individual components of cells? a beam of electrons high temperatures radioactive isotopes special stains

special stains

What part of ATP is broken to release energy for use in chemical reactions? the adenosine molecule the bond between the first and second phosphates the bond between the first phosphate and the adenosine molecule the bond between the second and third phosphates

the bond between the second and third phosphates

What do double bonds in phospholipid fatty acid tails contribute to? the fluidity of membranes the hydrophobic nature of membranes the hydrophilic nature of membranes preventing high temperatures from increasing fluidity of membranes

the fluidity of membranes

Which of the following is an example of passive transport across a membrane? the movement of H+H+ into a thylakoid disc during photosynthesis the uptake of glucose in the intestine the uptake of mineral ions into root hair cells of plants the movement of water from the descending loop of a nephron into the interstitium

the uptake of mineral ions into root hair cells of plants

. What is the function of enzymes? to increase the free energy of reactions to increase the the sum of the heats of formation to lower the randomness of the chemicals in the reaction to lower the activation energy of a reaction

to lower the activation energy of a reaction

. If glucose is broken down through aerobic respiration, a number of ATP can be made from the energy extracted. How many ATP are possible? 2 to 4 36 to 38 10 to 12 24 to 30

36 to 38

Which of the following molecules is likely to have the most potential energy? ATP ADP glucose sucrose

ADP

What is ATP made from? adenosine + high energy electrons ADP + phosphate AMP + ADP the conversion of guanine to adenosine

ADP + phosphate

When cellular respiration occurs, what is the primary molecule used to store the energy that is released? AMP ATP mRNA phosphate

ATP

Evaluating the diagram shown, how does ATP supply energy to chemical reactions? ATP dissociates and the energy released by breaking of a phosphate bond within ATP is used for phosphorylation of another molecule. ATP hydrolysis also provides energy to power coupling reactions. ATP utilizes energy to power exergonic reactions by hydrolysis of ATP molecule. The free energy released as a result of ATP breakdown is used to carry out metabolism of products. ATP utilizes energy to power endergonic reactions by dehydration of ATP molecule. The free energy released as a result of ATP breakdown is used to carry out metabolism of products. ATP utilizes the energy released from the coupling reactions and that energy is used to power the endergonic and exergonic reactions.

ATP dissociates and the energy released by breaking of a phosphate bond within ATP is used for phosphorylation of another molecule. ATP hydrolysis also provides energy to power coupling reactions.

What reaction will release the largest amount of energy to help power another reaction? AMP to ATP ATP to ADP DNA to proteins glucose to starch

ATP to ADP

Which of the following statements is part of the cell theory? All living organisms are made of cells. All cells contain DNA that they pass on to daughter cells. All cells depend on their surroundings to provide energy. All cells have a nucleus.

All living organisms are made of cells.

What is an anabolic pathway? Which of these is an example of an anabolic pathway used by cells in their metabolism? Anabolic pathways involve the breakdown of nutrient molecules into usable forms. An example is the harvesting of amino acids from dietary proteins. Anabolic pathways involve the breakdown of nutrient molecules into useable forms. An example is the use of glycogen by the liver to maintain blood glucose levels. Anabolic pathways build new molecules out of the products of catabolic pathways. An example is the separation of fatty acids from triglycerides to satisfy energy needs. Anabolic pathways build new molecules out of the products of catabolic pathways. An example is the linkage of nucleotides to form a molecule of mRNA.

Anabolic pathways build new molecules out of the products of catabolic pathways. An exampleis the linkage of nucleotides to form a molecule of mRNA.

The major role of the cell wall in bacteria is protecting the cell against changes in osmotic pressure, pressure caused by different solute concentrations in the environment. Bacterial cells swell, but do not burst, in low solute concentrations. What happens to bacterial cells if a compound that interferes with the synthesis of the cell wall is added to an environment with low solute concentrations? Bacterial cells will shrink due to the lack of cell wall material. Bacterial cells will shrink in size. Bacterial cells may burst due to the influx of water. Bacterial cells remain normal; they have alternative pathways to synthesize cell walls.

Bacterial cells may burst due to the influx of water.

What is a difference between prokaryotic and eukaryotic​ cells? Both cells have a nucleus but prokaryotic cells lack cytoplasm. Both cells have cytoplasm but prokaryotic cells lack a nucleus. Both cells have DNA but prokaryotic cells lack a cell membrane. Both cells have a cell membrane but prokaryotic cells lack DNA.

Both cells have cytoplasm but prokaryotic cells lack a nucleus.

According to the fluid mosaic model of the plasma cell membrane, what is the location of carbohydrates in the cell membranes? Carbohydrates are in contact with the aqueous fluid both inside and outside the cell. Carbohydrates are present only on the interior surface of a membrane. Carbohydrates are present only on the exterior surface of a membrane. Carbohydates span only the interior of a membrane.

Carbohydrates are present only on the exterior surface of a membrane.

. Does physical exercise involve anabolic processes, catabolic processes, or both? Give evidence for your answer. Physical exercise involves both catabolic and anabolic processes. Glucose is broken down into simpler compounds during physical activity to provide energy for forming molecules in anabolic pathway. Those molecules are then used to provide energy to the muscles for contraction. Physical exercise is just a catabolic process. Glucose is broken down into simpler compounds during physical activity and the simpler compounds are then used to provide energy to the muscles for contraction. Physical activity involves only anabolic processes. Glucose is broken down into simpler compounds during physical activity and the simpler compounds are then used to provide energy to the muscles for contraction by anabolic pathways. Physical exercise involves both anabolic and catabolic processes. Cellulose is broken down into simpler compounds during physical activity. The simpler compounds are then used to provide energy to the muscles for contraction by anabolic pathways.

Physical exercise involves both catabolic and anabolic processes. Glucose is broken down into simpler compounds during physical activity to provide energy for forming molecules in anabolic pathway. Those molecules are then used to provide energy to the muscles for contraction.

. Which of these is a possible explanation for the presence of a rigid cell wall in plants? Plants remain exposed to changes in temperature and thus require rigid cell walls to protect themselves. Plants are subjected to osmotic pressure and a cell wall helps them against bursting or shrinking. Plant cells have a rigid cell wall to protect themselves from grazing animals. Plant cells have a rigid cell wall to prevent the influx of waste material.

Plants are subjected to osmotic pressure and a cell wall helps them against bursting or shrinking.

What is the difference between primary and secondary active transport? Primary active transport is indirectly dependent on ATP, while secondary active transport is directly dependent on ATP. Primary active transport is directly dependent on ATP, while secondary active transport is indirectly dependent on ATP. Primary active transport does not require ATP, while secondary active transport is indirectly dependent on ATP. Primary active transport is indirectly dependent on ATP, while secondary active transport does not require ATP

Primary active transport is directly dependent on ATP, while secondary active transport is indirectly dependent on ATP.

What are the structural and functional similarities and differences between mitochondria and chloroplasts? Similarities: double membrane, inter-membrane space, ATP production, contain DNA. Differences: mitochondria have inner folds called cristae, chloroplast contains accessory pigments in thylakoids, which form grana and a stroma. Similarities: DNA, inter-membrane space, ATP production, and chlorophyll. Differences: mitochondria have a matrix and inner folds called cristae; chloroplast contains accessory pigments in thylakoids, which form grana and a stroma. Similarities: double membrane and ATP production. Differences: mitochondria have inter-membrane space and inner folds called cristae; chloroplast contains accessory pigments in thylakoids, which form grana and a stroma. Similarities: double membrane and ATP production. Differences: mitochondria have inter-membrane space, inner folds called cristae, ATP synthase for ATP synthesis, and DNA; chloroplast contains accessory pigments in thylakoids, which, form grana and a stroma.

Similarities: double membrane and ATP production. Differences: mitochondria have inter-membrane space, inner folds called cristae, ATP synthase for ATP synthesis, and DNA; chloroplast contains accessory pigments in thylakoids, which, form grana and a stroma.