1.
Which statement best describes the relationship that exists among proteins, DNA, and cells?
Correct Answer
D. Cells contain DNA, which controls the production of proteins.
Explanation
Cells contain DNA, which controls the production of proteins. This statement accurately describes the relationship among proteins, DNA, and cells. DNA contains the instructions for making proteins, and these proteins are essential for the structure and function of cells. Therefore, DNA controls the production of proteins within cells.
2.
Which type of molecule do whales use for energy storage and insulation?
Correct Answer
B. Fat
Explanation
Whales use fat molecules for energy storage and insulation. Fat is an efficient molecule for storing energy as it contains more than twice the amount of energy per gram compared to carbohydrates like glucose or starch. Additionally, fat provides insulation by forming a layer under the whale's skin, helping them to stay warm in cold water.
3.
Some microorganisms, such as yeast, produce energy in an oxygen-free environments through the process of ___.
Correct Answer
C. Anaerobic respiration
Explanation
Anaerobic respiration is the correct answer because microorganisms like yeast can produce energy in the absence of oxygen through this process. Anaerobic respiration involves the breakdown of glucose or other organic compounds to produce energy in the form of ATP without the use of oxygen. This process is less efficient than aerobic respiration but allows microorganisms to survive in oxygen-deprived environments.
4.
Which statement correctly identifies the cells?
Correct Answer
A. Cell 1 is prokaryotic; cell 2 is eukaryotic.
Explanation
The correct answer is that Cell 1 is prokaryotic and Cell 2 is eukaryotic. This is because prokaryotic cells lack a nucleus and membrane-bound organelles, while eukaryotic cells have a nucleus and membrane-bound organelles. Therefore, based on this information, Cell 1 must be prokaryotic and Cell 2 must be eukaryotic.
5.
Antibodies are composed primarily of amino acids. In which class of biomolecules would antibodies belong?
Correct Answer
A. Proteins
Explanation
Antibodies are composed primarily of amino acids, which are the building blocks of proteins. Therefore, antibodies belong to the class of biomolecules known as proteins.
6.
Proteins are synthesized in which organelle?
Correct Answer
A. 3
Explanation
Proteins are synthesized in the ribosomes, which are located in the cytoplasm of the cell. The ribosomes are responsible for reading the genetic information from the DNA and using it to assemble amino acids into proteins. Therefore, option 3 is the correct answer as it indicates the ribosomes as the organelle where proteins are synthesized.
7.
In a typical animal cell, which component contains the greatest amount of water?
Correct Answer
A. Cytoplasm
Explanation
The cytoplasm contains the greatest amount of water in a typical animal cell. The cytoplasm is a gel-like substance that fills the cell and contains various organelles, such as the ribosomes and nucleus. It is primarily composed of water, which makes up the majority of its volume. The cytoplasm provides a medium for cellular processes to occur and helps maintain the cell's shape and structure. Therefore, it is logical to conclude that the cytoplasm contains the greatest amount of water in an animal cell.
8.
The diagram shows a section of a cell membrane that includes a channel protein. The function of this protein is to __.
Correct Answer
A. Allow certain substances to enter or leave the cell
Explanation
The diagram shows a channel protein in a cell membrane. Channel proteins are known for their function of facilitating the movement of specific substances across the cell membrane. They create a passageway or channel that allows certain substances to enter or leave the cell, while selectively excluding others. This process is crucial for maintaining the balance of molecules and ions inside and outside the cell, and for regulating various cellular processes such as nutrient uptake and waste removal. Therefore, the correct answer is "allow certain substances to enter or leave the cell."
9.
This diagram shows a plant cell. Which structure is found in a plant cell but is absent in an animal cell?
Correct Answer
A. 4
Explanation
The diagram shows four structures labeled 1, 2, 3, and 4. The question asks which structure is found in a plant cell but absent in an animal cell. Since the answer is 4, it can be inferred that structure 4 is unique to plant cells and not present in animal cells.
10.
A freshwater plant is placed in a container of saltwater. What will most likely happen to the cells of the plant?
Correct Answer
C. They will shrink because water will move out of them.
Explanation
When a freshwater plant is placed in a container of saltwater, the surrounding saltwater has a higher concentration of salt compared to the plant cells. This creates a hypertonic environment, meaning that the concentration of solutes is higher outside the cells than inside. As a result, water will move out of the plant cells through osmosis, causing them to shrink or shrink. Therefore, the correct answer is "They will shrink because water will move out of them."