1.
Only eukaryotic cells have ________.
Correct Answer
B. Membrane-bound organelles
Explanation
Eukaryotic cells are characterized by the presence of membrane-bound organelles. These organelles, such as the nucleus, mitochondria, and endoplasmic reticulum, are enclosed by a membrane that separates their contents from the rest of the cell. This membrane allows for compartmentalization and specialization of cellular functions, which is a defining feature of eukaryotic cells. In contrast, prokaryotic cells, such as bacteria, lack membrane-bound organelles and have a simpler internal structure. Therefore, only eukaryotic cells have membrane-bound organelles.
2.
A particularly active cell might contain large numbers of
Correct Answer
C. Mitochondria
Explanation
Mitochondria are known as the powerhouses of the cell, responsible for producing energy in the form of ATP through cellular respiration. They are highly active organelles and can be found in large numbers in cells that require a lot of energy, such as muscle cells. Therefore, it is logical to conclude that a particularly active cell would contain large numbers of mitochondria.
3.
Megan examines a liver cell and observes an organelle with many smooth-sided channels. Which activity would identify this organelle as the Golgi apparatus?
Correct Answer
B. Detoxification of poisonous molecules within the cell
4.
Naomi adds cyclohexamide to cells grown in a test tube. Within minutes, she identifies short incomplete segments of proteins in the cells. On which organelle does cycloheximide act?
Correct Answer
B. Golgi Apparatus
Explanation
Cycloheximide is an inhibitor of protein synthesis, specifically targeting the ribosomes. By adding cycloheximide to the cells and observing the formation of short incomplete protein segments, it suggests that the ribosomes are being affected. The Golgi apparatus is involved in the modification, sorting, and packaging of proteins, but it is not the direct target of cycloheximide. Therefore, the correct answer is Ribosome.
5.
The presence of which structure indicates that cells are NOT photosynthetic bacteria?
Correct Answer
D. Ribosome
Explanation
Ribosomes are present in all types of cells, including photosynthetic bacteria. Therefore, the presence of ribosomes does not indicate whether cells are photosynthetic or not.
6.
Which structure in the cell is responsible for protein synthesis?
Correct Answer
A. Ribosome
Explanation
Ribosomes are responsible for protein synthesis in the cell. They are small, spherical organelles found in both prokaryotic and eukaryotic cells. Ribosomes are composed of ribosomal RNA (rRNA) and proteins. They are involved in translating the genetic information from the DNA into proteins. Ribosomes can be found either free-floating in the cytoplasm or attached to the endoplasmic reticulum. They read the messenger RNA (mRNA) and use it as a template to synthesize proteins by linking amino acids together in a specific sequence. Therefore, ribosomes play a crucial role in protein synthesis.
7.
Which structure in the cell regulates which materials can enter or leave the cell?
Correct Answer
A. Nuclear Membrane
Explanation
The nuclear membrane is responsible for regulating what materials can enter or leave the cell. It acts as a barrier, controlling the movement of molecules in and out of the nucleus. This selective permeability allows for the protection of the genetic material inside the nucleus and ensures that only necessary substances are allowed to enter or exit the cell.
8.
Which structure in the cell helps with detoxification and assembling materials for use in the cell membrane?
Correct Answer
D. Smooth Endoplasmic Reticulum
Explanation
The smooth endoplasmic reticulum is responsible for detoxification and assembling materials for use in the cell membrane. It is involved in the synthesis of lipids, including phospholipids, which are important components of the cell membrane. It also plays a role in the metabolism of carbohydrates and the detoxification of drugs and toxins. The smooth endoplasmic reticulum lacks ribosomes, which gives it a smooth appearance under a microscope, hence its name.
9.
Which structure in the cell is the fluid inside the cell that acts as a site for chemical reactions?
Correct Answer
B. Cytosol
Explanation
Cytosol is the correct answer because it is the fluid inside the cell that acts as a site for chemical reactions. It contains various enzymes and molecules necessary for metabolic processes. Chlorophyll is a pigment found in chloroplasts that is responsible for photosynthesis. Vacuole is a membrane-bound organelle involved in storage and Nucleoplasm is the fluid inside the nucleus.
10.
Which structure in the cell packages proteins for transport out of the cell?
Correct Answer
C. Golgi Apparatus
Explanation
The Golgi Apparatus is responsible for packaging proteins for transport out of the cell. It receives proteins from the rough endoplasmic reticulum and modifies them, adding sugars and lipids to create glycoproteins and lipoproteins. It then packages these proteins into vesicles and transports them to the cell membrane for secretion. The Golgi Apparatus plays a crucial role in the sorting, modifying, and packaging of proteins for export from the cell.
11.
Which structure in the cell modifies and transports proteins that will be sent outside of the cell?
Correct Answer
B. Rough Endoplasmic Reticulum
Explanation
The rough endoplasmic reticulum (RER) is responsible for modifying and transporting proteins that will be sent outside of the cell. It has ribosomes attached to its surface, giving it a rough appearance, and these ribosomes are involved in protein synthesis. The RER modifies the newly synthesized proteins by adding sugars and lipids, and then packages them into vesicles for transport to the Golgi apparatus. From there, the proteins can be further modified and sorted before being sent outside of the cell.
12.
Which structure in the cell contains the instructions for making proteins
Correct Answer
D. Nucleus
Explanation
The nucleus is the correct answer because it is the control center of the cell and contains the genetic material, which includes the instructions for making proteins. The DNA in the nucleus is transcribed into RNA, which is then transported out of the nucleus to the ribosomes for protein synthesis. The nucleolus, nuclear envelope, and ribosomes are all involved in protein synthesis, but they do not directly contain the instructions for making proteins.
13.
Which structure in the cell is responsible for assembling ribosomes?
Correct Answer
A. Nucleolus
Explanation
The structure responsible for assembling ribosomes in the cell is the nucleolus. The nucleolus is a region within the nucleus where ribosomal RNA (rRNA) is synthesized and ribosome assembly occurs. It is composed of proteins and nucleic acids and plays a crucial role in protein synthesis. The nucleolus also contains the genes that encode for rRNA, which is essential for the production of ribosomes. Therefore, the nucleolus is the correct answer for this question.
14.
Which structure in the cell is responsible for providing the cell with energy through the process of cellular respiration?
Correct Answer
B. Mitochondria
Explanation
Mitochondria are responsible for providing the cell with energy through the process of cellular respiration. They are known as the "powerhouses" of the cell because they produce ATP, the main source of energy for cellular activities. Mitochondria have their own DNA and are able to generate energy by breaking down glucose and other molecules through a series of chemical reactions. This process, known as cellular respiration, occurs in the mitochondria's inner membrane and produces ATP, which is then used by the cell for various metabolic processes.
15.
What are 3 structures that you would find in a plant cell but NOT in animal cell?
Correct Answer
D. All of the above are correct
Explanation
All of the above structures (Chloroplast, Cell Wall, and Vacuole) are found in plant cells but not in animal cells. Chloroplasts are responsible for photosynthesis, which is the process of converting sunlight into energy. Cell walls provide support and protection to plant cells. Vacuoles are large, fluid-filled sacs that store water, nutrients, and waste materials. These structures are unique to plant cells and play important roles in their structure and function.