Biology - Keystone Review - 2021

Membrane organelles known as ____ contain enzymes specialized to break down ingested materials, secretions, and wastes. A. lysosomes B. chloroplasts C. vacuoles D. ribosomes

A. lysosomes

The diagrams below display different types of cells as viewed by a microscope under low magnification. These diagrams demonstrate how cells can be differentiated by their ___ . A. modes of locomotion. B. cell structures. C. means of replication. D. sizes and densities.

A. modes of locomotion

Multicellular organisms are composed of a variety of living structures that are formed when cells differentiate. How could the living structure pictured below be classified? A.organ B.cell C.organism D.tissue

A. organ

The life forms exhibiting the simplest cellular structure are ___. A. prokaryotes B. eukaryotes C. organelles D. proteins

A. prokaryotes

The diagram below represents a stage of mitosis in which the chromosomes line up in the middle of the cell. What is the name of this phase of mitosis? A. Metaphase B. Prophase C. Anaphase D. Telophase

A. Metaphase

Before a cell enters mitosis, what happens to the genetic information in that cell? A. The information is duplicated. B. The information is completely changed. C. The information is halved. D. The information is selectively mutated.

A. The information is duplicated.

Carbohydrates are composed of which three elements? A. carbon, hydrogen, and oxygen B. oxygen, hydrogen, and nitrogen C. carbon, nitrogen, and phosphorus D. oxygen, sulfur, and phosphorus

A. carbon, hydrogen, and oxygen

Carbon atoms have four electrons in their outer shell. This means that a single carbon atom can form up to ____ bonds with other atoms. A. four B. two C. six D. eight

A. four

How does the size of a eukaryotic organism normally compare to the size of a prokaryotic organism? A. Eukaryotes and prokaryotes are both usually very small organisms. B. Eukaryotes are usually much larger than prokaryotes. C. Eukaryotes and prokaryotes are both usually very large organisms. D. Eukaryotes are usually much smaller than prokaryotes.

B. Eukaryotes are usually much larger than prokaryotes.

Both eukaryotic cells and prokaryotic cells possess DNA and engage in genetic processes. Which of the following is true of their cellular genetics? A. Prokaryotic DNA cannot be translated into proteins because of the lack of a nucleus. B. Eukaryotic DNA is linear, whereas most prokaryotic DNA is circular. C. Eukaryotic cells generally require fewer genes to operate than prokaryotic cells. D. Eukaryotic and prokaryotic DNA use different genetic codes (i.e. nucleotides).

B. Eukaryotic DNA is linear, whereas most prokaryotic DNA is circular.

Which of the following occurs during the interphase stage of the cell cycle? I.DNA is replicated. II.The cell divides. III.The cell grows in size. A. II only B. I and III only C. I, II, and III D. I and II only

B. I and III only

Suppose that the temperature in the ecosystem below dips below freezing. What would happen to the fish swimming in the lake? A. The fish would die because the lake would freeze solid. B. Ice would form on the surface of the lake and insulate the fish. C. The fish would move more rapidly to increase their body temperature. D. Ice would only form on the bottom of the lake, so the fish would be okay.

B. Ice would form on the surface of the lake and insulate the fish.

Which of the following is true about cells? A. Neither prokaryotic cells nor eukaryotic cells ever contain both a true nucleus that is well-defined and organelles that are separated from the cytoplasm by membranes. B. In general, prokaryotic cells do not have a true nucleus or membrane-bound organelles, whereas eukaryotic cells contain both a nucleus and organelles enclosed by membranes. C. In general, eukaryotic cells do not have a true nucleus or membrane-bound organelles, whereas prokaryotic cells contain both a nucleus and organelles enclosed by membranes. D. Both eukaryotic cells and prokaryotic cells always contain both a true nucleus that is well-defined and organelles that are separated from the cytoplasm by membranes.

B. In general, prokaryotic cells do not have a true nucleus or membrane-bound organelles, whereas eukaryotic cells contain both a nucleus and organelles enclosed by membranes.

Proteins can perform many different functions in living cells. One major function—acting as a catalyst for chemical reactions—can also be performed by what other kind of organic molecule? A. cholesterol B. RNA C. phospholipids D. glycogen

B. RNA

Sugars such as glucose, fructose, and ribose are examples of... A. lipids B. carbohydrates C. proteins D. nucleic acids

B. carbohydrates

Cytokinesis is a process that occurs during the cell cycle. During cytokinesis... A. the cell grows and performs normal life processes. B. the cytoplasm is divided to form two separate cells. C. the chromosomes of the cell are duplicated. D. the nuclear material of the cell is divided.

B. the cytoplasm is divided to form two separate cells.

The carp fish has 104 chromosomes in its body cells. When the fish's body cells divide by mitosis, how many chromosomes will each daughter cell have? A. 52 B. 312 C. 104 D. 208

C. 104

Water is the most abundant molecule found in living organisms. Most mammals, in fact, are approximately 70% water by weight. About two-thirds of this water is present inside cells. The other one-third is present outside cells (e.g., in blood plasma or other body fluids). Why is water so important to cells? A. Water determines which proteins are translated from the cellular DNA. B. The main structural component found in plasma membranes and cell walls is water. C. Almost all the chemical reactions in life processes occur in solutions with water. D. Water is stored in the cells to be used when the organism gets thirsty.

C. Almost all the chemical reactions in life processes occur in solutions with water.

During the cell cycle, A. DNA is replicated during mitosis. B. DNA is replicated once before mitosis and again before cytokinesis. C. DNA is replicated before mitosis begins. D. DNA is replicated directly after the completion of mitosis.

C. DNA is replicated before mitosis begins.

Which of the following is true of prokaryotic cells? A. They tend to be large and complex in comparison to eukaryotic cells. B. They contain nuclei and other membrane-bound organelles. C. They function as individual organisms. D. They may be found in unicellular or multicellular organisms

C. They function as individual organisms.

When a group of cells work together, such as in bones, muscles, or nerves, they are known as ______. A. an organism B. an organelle C. a tissue D. an organ

C. a tissue

Prokaryotic and eukaryotic cells have many differences, but they also share some common features. Which of the following may be found in either type of cell? A. Golgi bodies B. mitochondria C. cell walls D. nuclei

C. cell walls

All living organisms share many characteristics necessary for life. For example, all organisms, including both prokaryotic and eukaryotic, A. have cells arranged into complex organ structures. B. can use abiotic factors to make their own food. C. must obtain and use energy for life processes. D. can sexually reproduce to produce unique offspring.

C. must obtain and use energy for life processes.

A polymer is a large molecule that forms when smaller molecules known as monomers bond covalently in a repeating pattern. There are many biological polymers such as nucleic acids, proteins, and starches.What are the monomer units that make up nucleic acids? A. fatty acids B. amino acids C. nucleotides D. glucose

C. nucleotides

During the interphase stage of the cell cycle... A. the cell divides into two identical daughter cells. B. the cell divides into two unique daughter cells. C. the cell's chromosomes are duplicated. D. the cell's chromosomes condense into rod-like structures.

C. the cell's chromosomes are duplicated.

Which phase of mitosis is represented in the diagram below? A. Metaphase B. Prophase C. Telophase D. Anaphase

D. Anaphase

Cells experience distinct cycles of activities, such as growth and division. These activities are summarized in the image below. Beginning in the G1 phase, proteins called cyclins begin to accumulate in the cell. Cyclins combine with certain molecules to form cyclin-dependent kinase complexes (Cdkcs), which activate and deactivate other cellular proteins. For example, cyclin B forms a Cdkc that controls the M stage of the cell cycle. This Cdkc turns on the proteins that are involved in mitosis, turns off the proteins that prevent mitosis, and even activates an enzyme complex that breaks down cyclin B. The loss of cyclin B signals the end of the M portion of the cycle. Notice that the concentrations of cyclin B peak during the mitosis stage.Based on the above graph, which cyclin forms the primary Cdkc that controls the G2 stage? A. Cyclin D B. Cyclin B C. Cyclin E D. Cyclin A

D. Cyclin A

Which of the following are examples of nucleic acids? A. glucose and starch B. saturated fats and unsaturated fats C. collagen and keratin D. DNA and RNA

D. DNA and RNA

Cell theory states that: A. cells are the basic unit of structure and function in living things. B. all living things are composed of cells. C. new cells are produced by existing cells. D. all of these answers are correct.

D. all of these answers are correct.

Protein molecules are composed of long chains of.. A. DNA B. ribosomes C. RNA D. amino acids

D. amino acids

Organic macromolecules called ___ are insoluble in water, are often found in biological membranes and other waterproof coverings, and have the ability to store energy for extended periods of time. A. carbohydrates B. proteins C. nucleic acids D. lipids

D. lipids

When new cells are formed through the process of mitosis, the number of chromosomes in the new cells... A. is half of that of the parent cell. B. decreases every time the cell divides. C. increases every time the cell divides. D. remains the same as in the parent cell.

D. remains the same as in the parent cell.

Mitosis most directly plays a role in.... A. the metabolic processes of a cell. B.the transport of nutrients within a cell. C. the growth of a cell after cell division. D. the division of a cell's nucleus.

D. the division of a cell's nucleus.

Cellular reproduction in multicellular organisms occurs through the process of mitosis. What is the purpose of mitosis? A. to replace old cells such as red blood cells B. to form gametes (e.g. sperm and ova) C.to replace old chromosomes D. to form new somatic cells

D. to form new somatic cells

What is the single most abundant compound in living organisms? A. fat B. sugar C. carbon D. water

D. water