TEAS 7 Chemistry: Essential Practice for Success

ATI TEAS 7

Chemistry

1. What type of bond involves the complete transfer of electrons between atoms?

A. Covalent bond
B. Ionic bond
C. Metallic bond
D. Hydrogen bond

Correct answer: B

Rationale: Ionic bond - Electrons are completely transferred from one atom to another, creating cations and anions with strong electrostatic attraction.

2. What is the tough, fibrous tissue that connects bones at joints called?

A. Cartilage
B. Ligaments
C. Tendons
D. Fascia

Correct answer: B

Rationale: The correct answer is B: Ligaments. Ligaments are the tough, fibrous tissue that connects bones at joints. They provide stability and support to the joints, preventing excessive movement that could result in injury. Cartilage is a smooth, rubbery tissue that covers the ends of bones and cushions joints. Tendons are fibrous cords that attach muscles to bones, allowing for movement. Fascia is a connective tissue that surrounds muscles, groups of muscles, blood vessels, and nerves, providing support and protection. Therefore, in this case, the term that specifically refers to the tissue connecting bones at joints is ligaments.

3. Which structure helps regulate body temperature by constricting or dilating in response to temperature changes?

A. Sebaceous glands
B. Hair follicles
C. Sweat glands
D. Langerhans cells

Correct answer: C

Rationale: The correct answer is C: Sweat glands. Sweat glands play a crucial role in regulating body temperature by producing sweat that evaporates from the skin surface, cooling the body when it's hot. Sweat glands can constrict to reduce sweating in cooler temperatures and dilate to increase sweating when the body needs to cool down. Sebaceous glands are responsible for producing oil to lubricate the skin and hair follicles help in hair growth. Langerhans cells are immune cells in the skin. Therefore, sweat glands are the structure specifically involved in regulating body temperature through constriction and dilation in response to temperature changes.

4. The energy absorbed during a chemical reaction is called:

A. Kinetic energy
B. Potential energy
C. Heat energy
D. Endothermic energy

Correct answer: D

Rationale: Endothermic means "inward heat," indicating energy is absorbed during the reaction.

5. During a healthy heartbeat, the P wave on an ECG represents

A. The repolarization of the ventricles.
B. The electrical conduction through the AV node.
C. The contraction phase of the ventricles (systole)
D. The depolarization of the atria.

Correct answer: D

Rationale: The correct answer is D: The P wave on an ECG represents the depolarization of the atria. During a healthy heartbeat, the P wave is the first positive deflection seen on the ECG and reflects the initiation of the electrical impulse in the atria, leading to atrial contraction. It is followed by the QRS complex, which represents the depolarization of the ventricles. Options A, B, and C are incorrect because the P wave specifically corresponds to atrial depolarization, not repolarization of the ventricles, electrical conduction through the AV node, or ventricular contraction. Understanding the sequence of electrical events in the heart as represented on an ECG is crucial for interpreting cardiac function and identifying potential abnormalities.