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What is the structure of DNA?
- A. Single-stranded, linear
- B. Double-stranded, linear
- C. Double-stranded, helix
- D. Single-stranded, helix
Correct Answer: C
Rationale: The correct answer is C: Double-stranded, helix. DNA is structured as a double helix formed by two strands of nucleotides. The nucleotides are paired with complementary bases (A-T and C-G) in the center, held together by hydrogen bonds. This double-stranded helical structure is a fundamental characteristic of DNA and essential for its function in storing genetic information. Choices A, B, and D are incorrect because DNA is not single-stranded; it consists of two strands that run antiparallel to each other and are connected via hydrogen bonds. Additionally, DNA does not have a linear structure but rather a helical one, providing stability and protection to the genetic information it carries.
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What is the anatomical term for the back of the body? Example: Shoulder blade.
- A. Anterior
- B. Superior
- C. Posterior
- D. Inferior
Correct Answer: C
Rationale: The correct answer is C: Posterior. 'Posterior' is the anatomical term that refers to the back of the body. It is the opposite of 'anterior,' which refers to the front of the body. 'Superior' typically describes a structure that is positioned above another structure, while 'inferior' refers to a structure that is below another. In this case, the term 'posterior' specifically indicates the back of the body, making it the most appropriate choice among the options provided.
Identify the correct sequence of the 3 primary body planes as numbered 1, 2, and 3 in the above image.
- A. Plane 1 is coronal, plane 2 is sagittal, and plane 3 is transverse.
- B. Plane 1 is sagittal, plane 2 is coronal, and plane 3 is medial.
- C. Plane 1 is coronal, plane 2 is sagittal, and plane 3 is medial.
- D. Plane 1 is sagittal, plane 2 is coronal, and plane 3 is transverse.
Correct Answer: A
Rationale: In the standard anatomical position, plane 1 (coronal/frontal plane) divides the body into anterior and posterior portions, plane 2 (sagittal plane) divides the body into left and right portions, and plane 3 (transverse/horizontal plane) divides the body into superior and inferior portions. Therefore, the correct sequence is Plane 1 as coronal, Plane 2 as sagittal, and Plane 3 as transverse, which corresponds to Choice A. Choice B is incorrect as it misidentifies the planes. Plane 2 cannot be coronal as it specifically divides the body into left and right portions. Choice C is incorrect as it misidentifies Plane 2 as sagittal when it should be coronal. Choice D is incorrect as it incorrectly designates Plane 2 as coronal when it should be sagittal, leading to an inaccurate sequence of the primary body planes.
Which plane divides the body into left and right halves?
- A. Sagittal/Median Plane
- B. Frontal/Coronal Plane
- C. Transverse/Cross-Section Plane
- D. Horizontal Plane
Correct Answer: A
Rationale: The correct answer is A: Sagittal/Median Plane. This plane divides the body into left and right halves. The Frontal/Coronal Plane (choice B) divides the body into front and back, while the Transverse/Cross-Section Plane (choice C) divides it into top and bottom. The Horizontal Plane (choice D) divides the body into upper and lower portions. Understanding these planes is essential in anatomy as they help describe the orientation and relationships of body structures.
What is the path of oxygenated blood flow in our body?
- A. From the heart directly to the brain
- B. From the lungs to the left atrium, then to the left ventricle, and out through the aorta
- C. From the body to the right atrium to the lungs
- D. From the left atrium directly to the aorta
Correct Answer: B
Rationale: Oxygenated blood flows from the lungs to the left atrium, then to the left ventricle, and is pumped out through the aorta to the body. This pathway ensures efficient oxygen delivery to the body's tissues and organs. Choice A is incorrect as oxygenated blood does not flow directly from the heart to the brain. Choice C is incorrect as it suggests a route from the body to the right atrium and then to the lungs, which is the pathway for deoxygenated blood. Choice D is incorrect as it describes a direct pathway from the left atrium to the aorta, skipping the left ventricle, which is essential for pumping blood to the body.
What macromolecules are formed from amino acids, and what are their roles?
- A. Lipids; store energy
- B. Carbohydrates; provide energy
- C. Proteins; perform various functions like catalysis, transport, and structural support
- D. Nucleic acids; store genetic information
Correct Answer: C
Rationale: The correct answer is C. Proteins are macromolecules formed from amino acids and have diverse roles, such as serving as enzymes, transport molecules, and providing structural support. They are essential for catalysis, cellular communication, immune response, and many other functions in living organisms. Choices A, B, and D are incorrect. Lipids are not formed from amino acids but from fatty acids and glycerol, mainly serving as energy storage molecules. Carbohydrates are composed of sugars and provide energy to the body. Nucleic acids, like DNA and RNA, are made up of nucleotides and store genetic information in cells.