ATI TEAS 7
Chemistry
1. Which of the following is the smallest part of an element that can still be recognized as that element?
- A. Electron
- B. Proton
- C. Neutron
- D. Atom
Correct answer: D
Rationale: An atom is the smallest unit of matter that retains the chemical properties of an element. It is composed of a nucleus containing protons and neutrons, and electrons that orbit the nucleus. The number of protons in the nucleus determines the atomic number of the element, and the number of neutrons determines the isotope of the element.
2. Hair follicles are openings in the skin that house
- A. Blood vessels (Blood vessels are not housed in hair follicles)
- B. Nerve endings (Nerve endings are present but not housed within)
- C. Hair shafts and hair roots
- D. Sebaceous glands (These glands are often attached to hair follicles)
Correct answer: C
Rationale: Hair follicles are structures in the skin that house both the hair shaft and the hair root. The hair shaft is the visible part of the hair that extends from the skin's surface, while the hair root is the part embedded within the hair follicle and extends into the deeper layers of the skin. The sebaceous glands, which produce sebum (an oily substance), are typically attached to hair follicles and help lubricate and protect the hair and skin. Blood vessels and nerve endings are present in the skin but are not housed within the hair follicles themselves. Therefore, the correct answer is C, as hair follicles contain both the hair shaft and hair root.
3. What is the process by which the body reabsorbs water from the large intestine?
- A. Dehydration
- B. Osmosis
- C. Filtration
- D. Secretion
Correct answer: B
Rationale: Rationale: - Dehydration (Option A) refers to the condition of having insufficient water in the body, not the process of water reabsorption in the large intestine. - Osmosis (Option B) is the movement of water across a semi-permeable membrane from an area of low solute concentration to an area of high solute concentration. In the large intestine, water is reabsorbed through osmosis to maintain the body's fluid balance. - Filtration (Option C) is a process where a liquid or gas passes through a filter to separate the components. It is not the primary mechanism for water reabsorption in the large intestine. - Secretion (Option D) is the release of substances from cells, but it is not the process by which the body reabsorbs water from the large intestine. Therefore, the correct process by which the body reabsorbs water from the large intestine is
4. In which medium does light propagate at its highest speed?
- A. Air
- B. Water
- C. Glass
- D. Diamond
Correct answer: A
Rationale: The correct answer is A: 'Air.' Light propagates at its highest speed in a vacuum, which is nearly the same as in air. In a vacuum, light travels at its maximum speed of approximately 299,792 kilometers per second. When light enters a medium like air, water, glass, or diamond, its speed decreases due to interactions with atoms and molecules in the medium. Among the options given, air is the closest medium to a vacuum in terms of light speed. Water, glass, and diamond have higher refractive indices than air, causing light to travel slower in these mediums. This is why air allows light to propagate at its highest speed compared to water, glass, and diamond.
5. The neutral theory of molecular evolution proposes that:
- A. Most mutations in DNA are selectively neutral and do not affect an organism's fitness.
- B. All mutations are beneficial and contribute to the adaptation of a population.
- C. The rate of evolution is primarily driven by strong directional selection pressures.
- D. Genetic drift plays a negligible role in shaping genetic variation within populations.
Correct answer: A
Rationale: Rationale: A) The neutral theory of molecular evolution, proposed by Motoo Kimura in the 1960s, suggests that the majority of mutations that occur in DNA are selectively neutral, meaning they do not have a significant impact on an organism's fitness. These neutral mutations are not subject to natural selection and are allowed to accumulate in populations over time. This theory helps explain the high levels of genetic variation observed within populations. B) Option B is incorrect because not all mutations are beneficial. Mutations can be neutral, harmful, or beneficial, and the neutral theory specifically focuses on the idea that many mutations are neutral in their effects. C) Option C is incorrect because the neutral theory suggests that evolution is not primarily driven by strong directional selection pressures. Instead, it emphasizes the role of genetic drift and the accumulation of neutral mutations in shaping genetic variation. D) Option D is incorrect because
6. Which blood vessels carry deoxygenated blood from the body back to the right atrium of the heart?
- A. Arteries
- B. Veins
- C. Capillaries
- D. Venules
Correct answer: B
Rationale: The correct answer is B: Veins. Veins are the blood vessels that carry deoxygenated blood from the body back to the heart. Arteries carry oxygenated blood away from the heart, while capillaries are tiny blood vessels where exchange of gases and nutrients occurs. Venules are small blood vessels that collect blood from capillaries and carry it to veins. Understanding the role of veins in carrying deoxygenated blood is crucial for comprehending the circulatory system and how blood is circulated throughout the body.
Similar Questions
Access More Features
ATI TEAS Premium Plus
$150/ 90 days
- Actual ATI TEAS 7 Questions
- 3,000 questions with answers
- 90 days access
ATI TEAS Basic
$99/ 30 days
- 3,000 Questions with answers
- 30 days access