what is the lysosome

ATI TEAS 7

TEAS 7 science practice

1. What is a lysosome?

A. A sac-like structure that contains enzymes that break down cellular components
B. A network of tubules that transport proteins and lipids throughout the cell
C. The site of protein synthesis
D. The site of cellular respiration

Correct answer: A

Rationale: A lysosome is a membrane-bound organelle found in animal cells that contains digestive enzymes. These enzymes are responsible for breaking down various cellular components, such as proteins, lipids, carbohydrates, and even foreign particles like bacteria. This breakdown process is crucial for maintaining cell health and function by recycling and disposing of cellular waste. Options B, C, and D are incorrect because lysosomes are not involved in transporting proteins and lipids throughout the cell (option B), protein synthesis (option C), or cellular respiration (option D). Lysosomes primarily function as the cell's 'recycling center' by breaking down and processing cellular materials.

2. Which division of the autonomic nervous system is responsible for the 'rest and digest' response, promoting relaxation and conservation of energy?

A. Sympathetic nervous system
B. Parasympathetic nervous system
C. Somatic nervous system
D. Central nervous system

Correct answer: B

Rationale: The correct answer is B: Parasympathetic nervous system. The parasympathetic nervous system is responsible for the 'rest and digest' response, promoting relaxation, conserving energy, and facilitating activities like digestion and lowering heart rate. The sympathetic nervous system, which is not the correct answer, triggers the 'fight or flight' response, preparing the body for stressful situations by increasing heart rate, dilating airways, and releasing adrenaline. The somatic nervous system (choice C) controls voluntary movements, not the autonomic functions related to 'rest and digest.' The central nervous system (choice D) includes the brain and spinal cord and is not specifically involved in the autonomic regulation of bodily functions like the 'rest and digest' response.

3. What is the monomer for nucleic acids?

A. Nucleotide
B. Amino acid
C. Phosphate group
D. Ribosome

Correct answer: A

Rationale: The correct answer is A: Nucleotide. Nucleotides are indeed the monomers that make up nucleic acids like DNA and RNA. They consist of a sugar molecule, a phosphate group, and a nitrogenous base. Amino acids are the monomers of proteins, not nucleic acids. While the phosphate group is a component of nucleotides, it is not the sole monomer. Ribosome is a cellular organelle involved in protein synthesis and is not a monomer for nucleic acids.

4. What are chromosomes made of?

A. DNA and RNA
B. DNA and protein
C. Protein and RNA
D. DNA and lipids

Correct answer: B

Rationale: Chromosomes are made up of DNA and associated proteins. These proteins help package and organize the DNA within the cell, playing a crucial role in gene regulation and cell division. While RNA is involved in various cellular processes, it is not a primary component of chromosomes. Lipids are not a fundamental component of chromosomes, which primarily consist of DNA and proteins.

5. When is a solution formed?

A. One substance dissolves in another
B. Two or more substances react chemically
C. A solid changes to a liquid
D. None of the above

Correct answer: A

Rationale: A solution is formed when one substance dissolves in another. This process creates a homogeneous mixture where the solute is dispersed in the solvent, resulting in a uniform composition throughout the mixture. Choice B is incorrect because chemical reactions involve the transformation of substances into new compounds, not the formation of solutions. Choice C is incorrect as it describes a physical change from a solid to a liquid, not the formation of a solution. Choice D is incorrect as one substance dissolving in another is the defining characteristic of a solution.