a solution is formed when

ATI TEAS 7

Mometrix TEAS 7 science practice test

1. 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.

2. What is the role of transfer RNA (tRNA) in protein synthesis?

A. Transcribes DNA into mRNA
B. Decodes the genetic code on mRNA
C. Carries specific amino acids to the ribosomes
D. Modifies the structure of proteins

Correct answer: C

Rationale: A) Transcribes DNA into mRNA: This is the function of RNA polymerase, not transfer RNA (tRNA). tRNA is involved in protein synthesis, not transcription. B) Decodes the genetic code on mRNA: This is the function of tRNA during translation. tRNA molecules carry specific amino acids and recognize the codons on mRNA, ensuring the correct amino acid is added to the growing polypeptide chain. C) Carries specific amino acids to the ribosomes: This is the primary role of tRNA in protein synthesis. Each tRNA molecule is specific for a particular amino acid and carries it to the ribosome, where it is added to the growing protein chain. D) Modifies the structure of proteins: This is not a function of tRNA. Protein modification can occur after translation is complete and involves other cellular processes and molecules.

3. Which organelle is responsible for the final stages of protein modification and packaging for secretion in animal cells?

A. Rough endoplasmic reticulum (RER)
B. Smooth endoplasmic reticulum (SER)
C. Ribosomes
D. Golgi apparatus

Correct answer: D

Rationale: The Golgi apparatus is responsible for the final stages of protein modification and packaging for secretion in animal cells. After proteins are synthesized in the rough endoplasmic reticulum (RER), they are transported to the Golgi apparatus for further processing, sorting, and packaging before being sent to their final destination within or outside the cell. The smooth endoplasmic reticulum (SER) is mainly involved in lipid metabolism and detoxification processes, not protein modification. Ribosomes are the cellular organelles responsible for protein synthesis, not the final stages of protein modification and packaging for secretion, which is the role of the Golgi apparatus.

4. The framework of bones, cartilage, ligaments, and tendons that provides structure, support, and facilitates movement is part of the:

A. Muscular system
B. Skeletal system
C. Nervous system
D. Endocrine system

Correct answer: B

Rationale: The skeletal system consists of bones, cartilage, ligaments, and tendons that work together to provide structure, support, protection for internal organs, and facilitate movement. It is responsible for supporting the body's framework and protecting vital organs. The muscular system (option A) consists of muscles that work with the skeletal system to produce movement but does not include bones, cartilage, ligaments, and tendons. The nervous system (option C) is responsible for transmitting signals throughout the body to control movement and other functions. The endocrine system (option D) is a collection of glands that produce hormones to regulate various bodily functions but is not primarily involved in structure, support, and movement as the skeletal system is.

5. What type of energy does an object in motion possess?

A. Potential energy
B. Kinetic energy
C. Thermal energy
D. Chemical energy

Correct answer: B

Rationale: The correct answer is B. Kinetic energy is the energy possessed by an object in motion. When an object is in motion, it has the ability to do work due to its motion, which is known as kinetic energy. Potential energy, choice A, refers to stored energy that has the potential to do work but is not related to motion. Thermal energy, choice C, is related to the temperature of an object, not its motion. Chemical energy, choice D, is energy stored in the bonds of chemical compounds and is not directly related to an object's motion.