what is the formula for calculating density

ATI TEAS 7

TEAS version 7 quizlet science

1. What is the formula for calculating density?

A. Density = Volume / Mass
B. Density = Mass Ã— Volume
C. Density = Mass / Volume
D. Density = Volume - Mass

Correct answer: A

Rationale: Density is defined as the amount of mass in a given volume. The formula for calculating density is Density = Mass / Volume. This means that you divide the mass of an object by its volume to determine its density. Therefore, the correct formula for calculating density is Density = Volume / Mass. Choice A is correct because density is calculated by dividing the volume by the mass. Choices B, C, and D are incorrect because they do not represent the correct relationship between mass and volume in calculating density.

2. What is the approximate composition of blood?

A. 45% plasma, 55% formed elements
B. 55% plasma, 45% formed elements
C. 55% water, 45% blood cells
D. 45% water, 55% plasma

Correct answer: B

Rationale: Blood is composed of approximately 55% plasma (mostly water with proteins, electrolytes, and nutrients) and 45% formed elements (red blood cells, white blood cells, and platelets). Choice B is the correct answer. Choice A is incorrect as it reverses the percentages. Choice C is incorrect because it incorrectly states that blood cells make up 45% of blood, while they are part of the formed elements along with platelets. Choice D is incorrect as it suggests that water makes up 45% of blood, which is not accurate.

3. How does meiosis differ from mitosis?

A. Meiosis is used for repairing the body. Mitosis is used for cell reproduction.
B. Meiosis is used for sexual reproduction. Mitosis is used for asexual reproduction.
C. Meiosis occurs in various organisms. Mitosis occurs in various organisms.
D. Meiosis produces cells that are genetically different. Mitosis produces cells that are genetically identical.

Correct answer: D

Rationale: Meiosis is the process of cell division that results in the formation of sex cells (gametes) with only half the number of chromosomes as the parent cell, leading to genetically different cells. In contrast, mitosis is a cell division process that produces two daughter cells that are genetically identical to each other and the parent cell, maintaining the same chromosome number. Therefore, the correct answer is D, as meiosis and mitosis differ in their genetic outcomes - meiosis results in genetic diversity, while mitosis maintains genetic identity. Choices A, B, and C are incorrect because they do not accurately distinguish between meiosis and mitosis. Meiosis is not used for repairing the body or asexual reproduction, and the occurrence of both processes in various organisms does not highlight their primary differences in genetic outcomes.

4. Which human body system is correctly matched with its function?

A. Respiratory system; exchanges oxygen and carbon dioxide in the lungs.
B. Circulatory system; transports oxygen to cells and removes carbon dioxide.
C. Lymphatic system; produces antibodies that destroy virally affected or foreign cells.
D. Endocrine system; regulates hormones controlling bodily functions and metabolism.

Correct answer: B

Rationale: The circulatory system is responsible for the transportation of oxygen from the lungs to all the body's cells and tissues, as well as removing carbon dioxide from the cells and transporting it back to the lungs to be exhaled. This process is crucial for cellular respiration and the exchange of gases necessary for bodily functions. Choice B accurately matches the role of the circulatory system by describing its function of transporting oxygen to cells and removing carbon dioxide, which is essential for maintaining proper cellular activities. Choices A, C, and D are incorrect because they do not accurately match the body system with its function. The respiratory system primarily involves the exchange of gases in the lungs, not transportation to cells; the lymphatic system deals with immunity through the production of antibodies, not gas exchange; and the endocrine system's main function is hormone regulation, not the transport of gases.

5. Which of the following is directly transcribed from DNA and represents the first step in protein synthesis?

A. siRNA
B. rRNA
C. mRNA
D. tRNA

Correct answer: C

Rationale: mRNA (messenger RNA) is directly transcribed from DNA in the nucleus during the process of transcription. It serves as a template for protein synthesis during translation in the cytoplasm. mRNA carries genetic information from the DNA to the ribosomes, where it determines the sequence of amino acids in a protein. Thus, mRNA represents the first step in protein synthesis as it carries the code from the DNA to be translated into a protein. Choice A, siRNA (small interfering RNA), is involved in post-transcriptional gene silencing and does not play a role in protein synthesis. Choice B, rRNA (ribosomal RNA), is a component of the ribosome and plays a structural and functional role in protein synthesis but is not directly transcribed from DNA. Choice D, tRNA (transfer RNA), is responsible for bringing amino acids to the ribosome during protein synthesis but is not directly transcribed from DNA.