Cp Bio 2 Cell Structure Quiz (Fall 2014)

The structure labeled A is the cell wall. The cell wall is a rigid outer layer found in plant cells, fungi, and some bacteria. It provides support and protection for the cell, helping to maintain its shape and prevent it from bursting under pressure. The cell wall is composed of cellulose, a complex carbohydrate that forms a strong and flexible network. It also allows substances to pass through small channels called plasmodesmata, facilitating communication and transport between neighboring cells.

The structure labeled A is the nucleus. The nucleus is a membrane-bound organelle found in eukaryotic cells. It contains the cell's genetic material, including DNA, and is responsible for controlling the cell's activities by regulating gene expression. The nucleus is often referred to as the "control center" of the cell because it plays a crucial role in maintaining cell function and coordinating cellular processes.

Mitochondria are labeled as D in the given structure. Mitochondria are double-membrane organelles found in most eukaryotic cells. They are responsible for producing energy in the form of ATP through cellular respiration. The inner membrane of mitochondria contains enzymes involved in the electron transport chain, which generates ATP. The presence of mitochondria in the labeled structure suggests that it is involved in energy production and metabolism within the cell.

Centrioles are small cylindrical structures found in animal cells that play a crucial role in cell division. They are responsible for organizing the spindle fibers during cell division and ensuring the proper separation of chromosomes. Centrioles are typically found in pairs and are located near the nucleus. They are composed of microtubules and are involved in various cellular processes, including cell motility and the formation of cilia and flagella. Therefore, structure F in this question is labeled as centrioles.

Structure C is labeled as rough E.R. because it has ribosomes attached to its surface. The rough E.R. is responsible for protein synthesis, as the ribosomes on its surface help in the production of proteins. This is in contrast to smooth E.R., which lacks ribosomes and is involved in lipid synthesis and detoxification. The presence of ribosomes on structure C indicates that it is rough E.R.

The cytoskeleton is a network of proteins that provides structural support and shape to a cell. It is composed of three main components: microtubules, microfilaments, and intermediate filaments. These proteins help to maintain the cell's shape, anchor organelles in place, and facilitate cell movement. The cytoskeleton also plays a crucial role in cell division and intracellular transport of materials. Therefore, the cytoskeleton is the correct answer as it best describes the network of proteins that supports and gives shape to a cell.

Structure B is labeled as smooth E.R. The smooth endoplasmic reticulum (ER) is a network of membrane-bound tubes and sacs involved in various cellular functions. Unlike the rough ER, it lacks ribosomes on its surface. The smooth ER is responsible for lipid synthesis, detoxification of drugs and toxins, and storage and release of calcium ions. Therefore, based on the given options, structure B is most likely to be the smooth ER.

Selective permeability refers to the property of a membrane or barrier that allows only certain molecules or ions to pass through while preventing others from doing so. In this case, the correct answer "some molecules pass" accurately describes selective permeability as it suggests that only certain molecules are able to pass through the membrane, while others are not able to pass through.

The statement "Viruses are the smallest type of cell" is not part of the Cell Theory because viruses are not cells. Viruses are considered to be acellular particles because they do not have the characteristics of living cells, such as the ability to reproduce on their own or carry out metabolic processes. Instead, they rely on host cells to replicate and carry out their life cycle. Therefore, viruses cannot be considered as the smallest type of cell according to the Cell Theory.

The main function of the Golgi apparatus is to process and deliver proteins. It receives proteins from the endoplasmic reticulum, modifies them by adding carbohydrates or lipids, and packages them into vesicles for transportation to their final destination within the cell or outside of the cell. This process ensures that proteins are properly sorted, processed, and delivered to their intended targets, allowing them to carry out their specific functions in the cell.

The cell wall is not found in an animal cell. Unlike plant cells, animal cells do not have a rigid cell wall made of cellulose. Instead, animal cells are surrounded by a flexible cell membrane that allows for movement and flexibility. The other options, mitochondria, Golgi apparatus, and vacuole, are all found in animal cells and play important roles in cellular functions such as energy production, protein processing, and storage.

E is labeled as the Golgi body. The Golgi body is an organelle found in eukaryotic cells that is involved in the processing, packaging, and distribution of proteins and lipids. It receives proteins and lipids from the endoplasmic reticulum and modifies them before packaging them into vesicles for transport to their final destination. The Golgi body consists of flattened membrane sacs called cisternae, which are responsible for the sorting and modification of molecules.

The central vacuole is a feature found only in plant cells. It is a large, membrane-bound organelle that occupies most of the cell's volume. It plays a crucial role in maintaining the cell's turgor pressure, storing water, nutrients, and waste products. Animal cells may have smaller vacuoles or none at all, making the central vacuole unique to plant cells. Mitochondria, nucleus, and centrioles are found in both plant and animal cells.

Structure B is labeled as chloroplast because chloroplasts are the organelles responsible for photosynthesis in plant cells. They contain chlorophyll, a pigment that captures sunlight and converts it into chemical energy. This energy is then used to produce glucose, which is the main source of energy for the plant. Chloroplasts are typically green in color due to the presence of chlorophyll.

Ribosomes can be found on the surface of the endoplasmic reticulum. The endoplasmic reticulum is a network of membranes within the cell that is involved in the synthesis, folding, and transport of proteins. Ribosomes are responsible for protein synthesis, and they can be found either free in the cytoplasm or attached to the endoplasmic reticulum. When ribosomes are attached to the endoplasmic reticulum, it is called rough endoplasmic reticulum due to the presence of ribosomes on its surface. Therefore, ribosomes are the organelles that can be found on the surface of the endoplasmic reticulum.

The nucleus is the storehouse for most of a cell's genetic information. It contains the cell's DNA, which carries the instructions for the cell's functions and characteristics. The DNA is organized into structures called chromosomes, which are found inside the nucleus. The nucleus also regulates the cell's activities and controls the expression of genes. Therefore, the nucleus plays a crucial role in storing and managing the cell's genetic information.

Structure C is labeled as vacuole. The vacuole is a membrane-bound organelle found in plant cells and some animal cells. It is responsible for storing water, ions, nutrients, and waste products. The vacuole also helps maintain the cell's shape and turgor pressure. In plant cells, the vacuole is typically larger and more prominent than in animal cells. It plays a crucial role in regulating the cell's internal environment and supporting various cellular processes.

This type of cell is an animal cell. Animal cells are eukaryotic cells, meaning they have a nucleus and other membrane-bound organelles. They are found in animals and are responsible for various functions such as metabolism, reproduction, and maintaining homeostasis. Animal cells do not have a cell wall like plant cells, and they lack chloroplasts. Bacterial cells are prokaryotic cells, which are structurally and functionally different from animal cells. Therefore, the correct answer is animal cell.

The picture is of a prokaryote cell. Prokaryote cells are simple cells that lack a nucleus and other membrane-bound organelles. They are typically smaller than eukaryote cells and can be found in bacteria and archaea. The absence of a nucleus distinguishes prokaryote cells from eukaryote cells, which have a nucleus and other membrane-bound organelles. Plant and animal cells are both examples of eukaryote cells.

A phospholipid is composed of a polar head and a nonpolar tail. The polar head of a phospholipid is made up of a phosphate group, which is hydrophilic or attracted to water. The nonpolar tail is made up of fatty acid chains, which are hydrophobic or repelled by water. This arrangement of a polar head and nonpolar tail allows phospholipids to form the main component of cell membranes, with the polar heads facing towards the watery environment inside and outside the cell, and the nonpolar tails facing inwards, creating a barrier that separates the cell from its surroundings.

A membrane-bound sac that contains digestive enzymes is called a lysosome. Lysosomes are organelles found in animal cells that play a crucial role in breaking down and recycling cellular waste materials, as well as in the digestion of macromolecules. They contain various hydrolytic enzymes that can break down proteins, lipids, carbohydrates, and nucleic acids. The enzymes within the lysosome are able to function optimally in the acidic environment created by the lysosomal membrane. Overall, lysosomes are essential for maintaining cellular homeostasis and proper functioning of the cell.

The term for the jelly-like substance that is contained inside the cell membrane is cytosol. Cytosol is the liquid component of the cytoplasm, which surrounds the organelles within the cell. It contains various molecules, such as proteins, ions, and nutrients, and serves as a medium for many cellular processes.

A eukaryotic cell is characterized by having a nucleus, which houses the DNA. In contrast, a prokaryotic cell lacks a true nucleus and its DNA is found in the cytoplasm. Therefore, the correct answer is that a prokaryotic cell does not have a nucleus.

Flagella are not found in plant cells. Flagella are whip-like structures that are used for movement in certain organisms, such as bacteria and sperm cells. Plant cells do not have flagella, as they have a rigid cell wall and are typically immobile. Instead, plant cells rely on other structures, such as the cell wall and cytoskeleton, for support and stability.

A vesicle is a membrane-bound sac that is used to transport substances into and out of cells. It acts as a small transport container within the cell, allowing molecules and other cellular components to be moved from one location to another. Vesicles are involved in processes such as endocytosis, exocytosis, and intracellular trafficking. They play a crucial role in maintaining the balance of substances within the cell and facilitating communication between different cellular compartments.

This cell is classified as a eukaryote cell because it contains a membrane-bound nucleus and other membrane-bound organelles. Eukaryotic cells are typically larger and more complex than prokaryotic cells, such as bacterial cells. Animal cells are a type of eukaryotic cell, but the given information does not specifically mention that this cell is from an animal. Therefore, the most accurate classification for this cell is eukaryote cell.

Amoeba proteus takes in food through the process of phagocytosis. Phagocytosis is a form of endocytosis where the cell engulfs solid particles or other cells by extending its membrane around them and forming a food vacuole. The food is then digested within the vacuole, allowing the organism to obtain nutrients and energy. This process is essential for the survival and growth of Amoeba proteus.

Active transport is the process that uses proteins to move molecules against the concentration gradient. Unlike passive transport, which relies on the natural flow of molecules from high to low concentration, active transport requires energy to pump molecules against this flow. This energy is provided by ATP, and the proteins involved in active transport are called pumps or transporters. Through active transport, cells are able to maintain a concentration gradient across their membranes and selectively transport specific molecules in or out of the cell.

The endoplasmic reticulum is responsible for making membranes and proteins. It is an organelle found in eukaryotic cells and is involved in various cellular processes, including protein synthesis and lipid metabolism. The endoplasmic reticulum has a network of membranes that extend throughout the cytoplasm, providing a large surface area for the synthesis of proteins and lipids. It also plays a role in protein folding, modification, and transport within the cell. Therefore, the endoplasmic reticulum is the correct answer for this question.

A centriole is a cylindrical structure found only in animal cells. It plays a crucial role in cell division by organizing the microtubules that form the spindle apparatus. This helps in the separation of chromosomes during mitosis and meiosis. Plant cells do not have centrioles, making it a feature exclusive to animal cells. The central vacuole is found in plant cells and is responsible for storage and maintaining turgor pressure. Mitochondria are present in both animal and plant cells and are responsible for energy production. The nucleus is also found in both types of cells and contains genetic material.

Phagocytosis is not a type of passive transport because it is an active process where cells engulf and internalize solid particles or large molecules. Passive transport, on the other hand, does not require energy and includes processes like facilitated diffusion, osmosis, and simple diffusion. In facilitated diffusion, molecules move across the cell membrane with the help of transport proteins. Osmosis is the movement of water molecules across a selectively permeable membrane. Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration.

The smooth endoplasmic reticulum is responsible for breaking down toxins and drugs in liver cells. This organelle contains enzymes, such as cytochrome P450, that aid in the detoxification process. These enzymes modify and break down various substances, including drugs and toxins, making them more water-soluble and easier to eliminate from the body. The rough endoplasmic reticulum is involved in protein synthesis, the Golgi apparatus is responsible for packaging and modifying proteins, and chloroplasts are found in plant cells and are responsible for photosynthesis.

When a cell is placed in a hypertonic solution, the concentration of solutes outside the cell is higher than inside the cell. As a result, water molecules move out of the cell through osmosis, causing the cell to lose water. This loss of water leads to the shrinkage or shriveling up of the cell.