Biology Final Chapter 4

1. The ER has two distinct regions that differ in structure and functions. Lipidsare synthesized within the _________ and proteins are synethesized within the __________

The smooth endoplasmic reticulum (ER) is responsible for lipid synthesis, while the rough ER is involved in protein synthesis. The smooth ER lacks ribosomes on its surface, allowing it to specialize in lipid metabolism, including the synthesis of various lipids. On the other hand, the rough ER is studded with ribosomes, which are responsible for protein synthesis. This distinction in structure and function allows the ER to carry out different processes within its two distinct regions.

Explanation

The smooth endoplasmic reticulum (ER) is responsible for lipid synthesis, while the rough ER is involved in protein synthesis. The smooth ER lacks ribosomes on its surface, allowing it to specialize in lipid metabolism, including the synthesis of various lipids. On the other hand, the rough ER is studded with ribosomes, which are responsible for protein synthesis. This distinction in structure and function allows the ER to carry out different processes within its two distinct regions.

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2. Prokaryotic cells are characteristics of _________ and ________

Prokaryotic cells are characterized by their lack of a nucleus and membrane-bound organelles. They are typically found in bacteria and archaea. Bacteria are single-celled microorganisms that can be found in various environments, while archaea are also single-celled microorganisms but are known for their ability to survive in extreme conditions. Both bacteria and archaea have prokaryotic cells, making them the correct answer.

Explanation

Prokaryotic cells are characterized by their lack of a nucleus and membrane-bound organelles. They are typically found in bacteria and archaea. Bacteria are single-celled microorganisms that can be found in various environments, while archaea are also single-celled microorganisms but are known for their ability to survive in extreme conditions. Both bacteria and archaea have prokaryotic cells, making them the correct answer.

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3. You look into a light microscope and view an unknown cell. what might you see that would tell you whether the cell is prokaryotic or eukaryotic

A ridgid cell wall

A nucleus

A plasma membrane

Ribosome

If you see a nucleus when looking into a light microscope, it would indicate that the cell is eukaryotic. Prokaryotic cells do not have a nucleus, while eukaryotic cells do. The presence of a nucleus is a key characteristic that distinguishes between these two types of cells.

Explanation

If you see a nucleus when looking into a light microscope, it would indicate that the cell is eukaryotic. Prokaryotic cells do not have a nucleus, while eukaryotic cells do. The presence of a nucleus is a key characteristic that distinguishes between these two types of cells.

4. Which best describes the structure of the plasma membrane

A proteins sandwiched between two layer of phosolipids

Proteins embedded in two layers of phospholipids

A layer of proteins coating a layer of phospholipids

Phospholipids embedded in two layers of proteins

The correct answer is "proteins embedded in two layers of phospholipids." The plasma membrane is composed of a phospholipid bilayer, with the hydrophilic heads facing outward and the hydrophobic tails facing inward. Proteins are embedded within this lipid bilayer, with some spanning across both layers and others only partially embedded. These proteins have various functions, including transport of molecules, cell signaling, and structural support. The arrangement of proteins within the phospholipid bilayer allows for the selective permeability of the plasma membrane and the regulation of cellular processes.

Explanation

The correct answer is "proteins embedded in two layers of phospholipids." The plasma membrane is composed of a phospholipid bilayer, with the hydrophilic heads facing outward and the hydrophobic tails facing inward. Proteins are embedded within this lipid bilayer, with some spanning across both layers and others only partially embedded. These proteins have various functions, including transport of molecules, cell signaling, and structural support. The arrangement of proteins within the phospholipid bilayer allows for the selective permeability of the plasma membrane and the regulation of cellular processes.

5. Emily would like to film the movement of chromosomes during cell division. her best choice for a microscope would be a

Light microscope, because of its magnfying power

Transmission electron microscope, because of its resolving power

Scanning electron microscope because the chromosomes are on the cell surface.

Light microscope becuase the specimen must be kept alive

The best choice for Emily to film the movement of chromosomes during cell division would be a light microscope because the specimen must be kept alive. Light microscopes are commonly used for observing living specimens as they use visible light to illuminate the sample without causing any damage. This allows Emily to study the dynamic process of cell division in real-time without harming the cells or disrupting their natural behavior.

Explanation

The best choice for Emily to film the movement of chromosomes during cell division would be a light microscope because the specimen must be kept alive. Light microscopes are commonly used for observing living specimens as they use visible light to illuminate the sample without causing any damage. This allows Emily to study the dynamic process of cell division in real-time without harming the cells or disrupting their natural behavior.