the defining characteristic of an element is determined by the number of

ATI TEAS 7

TEAS 7 science practice

1. What determines the defining characteristic of an element?

A. Neutrons in its nucleus
B. Electrons surrounding the nucleus
C. Protons in its nucleus
D. All of the above

Correct answer: C

Rationale: The defining characteristic of an element is determined by the number of protons in its nucleus, which is referred to as the atomic number. The number of protons uniquely identifies an element. The correct answer is choice C because the number of protons in the nucleus of an atom defines its elemental identity, as different elements have a unique number of protons. Neutrons and electrons do play essential roles in the atom, but they do not determine the defining characteristic of an element. Neutrons contribute to the stability of the nucleus and isotopes of an element, while electrons are involved in chemical bonding and the reactivity of an atom.

2. What is the primary function of the cell membrane?

A. To provide structural support for the cell
B. To transport substances in and out of the cell
C. To synthesize proteins and lipids
D. To store genetic material

Correct answer: B

Rationale: The primary function of the cell membrane, also known as the plasma membrane, is to regulate the movement of substances in and out of the cell. It acts as a selectively permeable barrier, allowing specific molecules to pass through while blocking others. This role is crucial for maintaining the internal environment of the cell by enabling essential nutrients to enter and waste products to exit. While the cell membrane provides some structural support for the cell, its main function is substance transport. Protein and lipid synthesis predominantly occur in organelles like the endoplasmic reticulum and Golgi apparatus, and storing genetic material is the nucleus's responsibility. Therefore, choices C (To synthesize proteins and lipids) and D (To store genetic material) are incorrect as these functions are carried out by other cell organelles, not the cell membrane.

3. What is the process of a fertilized egg attaching itself to the uterine lining called?

A. Ovulation
B. Implantation
C. Parturition
D. Menstruation

Correct answer: B

Rationale: Implantation is the correct answer. It is the process in which a fertilized egg attaches itself to the uterine lining, where it will develop into an embryo and eventually a fetus. Ovulation, on the other hand, is the release of an egg from the ovary. Parturition refers to the process of giving birth, while menstruation is the shedding of the uterine lining if fertilization does not occur. Therefore, the process described in the question specifically pertains to implantation.

4. A car is accelerating down a hill. Which of the following forces is NOT acting on the car?

A. Gravitational force
B. Normal force from the road
C. Air resistance
D. The car's engine force

Correct answer: B

Rationale: When a car is accelerating down a hill, the normal force from the road is not acting on the car. The normal force is the force exerted by a surface to support the weight of an object resting on it. As the car moves downhill, the normal force decreases since the road is no longer pushing back against the car's weight due to the downhill motion. Gravitational force pulls the car downhill, air resistance opposes the car's motion, and the car's engine force propels it forward. Therefore, the correct answer is B, as the normal force from the road is not acting on the car while it accelerates downhill.

5. What are some potential applications of understanding atomic structure in modern technology?

A. Designing new materials with tailored properties.
B. Developing advanced electronics and nanotechnology.
C. Improving nuclear energy production and safety.
D. All of the above.

Correct answer: D

Rationale: Understanding atomic structure is essential for various technological advancements. Designing new materials with tailored properties necessitates knowledge of atomic structure to effectively manipulate their characteristics. Developing advanced electronics and nanotechnology involves working at the atomic level to create smaller, faster, and more efficient devices. Improving nuclear energy production and safety also heavily depends on understanding atomic structure to enhance reactor design and safety measures. Therefore, all the options provided (A, B, and C) are potential applications of understanding atomic structure in modern technology.