ati teas 7 science

Correct Answer: A

Rationale: The correct answer is A: Femur (thigh bone). The femur is the largest bone in the human body, providing structural support and mobility for the lower body. It is located in the thigh region and is crucial for walking, running, and overall movement. The other choices, B: Tibia, C: Humerus, and D: Scapula, are all significant bones in the body, but they are not as large as the femur. The tibia is the second largest bone but is smaller than the femur. The humerus is in the upper arm, and the scapula is in the shoulder, so they are not as large as the femur which is in the lower body and bears more weight.

Correct Answer: B

Rationale: The correct answer is B: Alveoli. Alveoli are tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide occurs during respiration. Oxygen from the air we breathe diffuses into the bloodstream, while carbon dioxide from the blood is released into the alveoli to be exhaled. The trachea (A) is a tube that carries air to and from the lungs, the bronchi (C) are branches of the trachea, and the diaphragm (D) is a muscle that helps with breathing but is not directly involved in gas exchange. Therefore, the alveoli are responsible for gas exchange in the respiratory system.

Correct Answer: C

Rationale: The correct answer is C: Ecology. Ecology is the scientific study of the relationships between organisms and their environment. It focuses on the interactions between living organisms and their surroundings. Zoology (A) is the study of animals, Botany (B) is the study of plants, and Genetics (D) is the study of genes and heredity, which are not directly related to the relationships between organisms and their environment. Therefore, Ecology is the most appropriate choice for this question.

Correct Answer: B

Rationale: The correct answer is B: 2H2 + O2 → 2H2O. This equation is balanced because there are equal numbers of each type of atom on both sides of the equation. Balancing involves adjusting the coefficients to ensure the conservation of mass. In this case, there are 2 hydrogen atoms on each side and 2 oxygen atoms on each side, making it balanced. Explanation for other choices: A: H2 + O2 → H2O - Not balanced, as there are 2 hydrogen atoms on the left but only 1 on the right. C: 3H2O → 2H2 + O2 - Not balanced, as there are 6 hydrogen atoms on the left but only 2 on the right. D: H2O → H2 + O2 - Not balanced, as there are 1 oxygen atom on the left but 2 on the right.

Correct Answer: B

Rationale: The correct answer is B: Cardiac muscle. Cardiac muscle is found exclusively in the heart, allowing it to contract rhythmically and involuntarily to pump blood throughout the body. Smooth muscle (A) is found in organs like the intestines and blood vessels, not in the heart. Skeletal muscle (C) is attached to bones and responsible for voluntary movements, while voluntary muscle (D) is a general term that refers to skeletal muscle controlled voluntarily. Therefore, the unique characteristics of cardiac muscle make it the correct answer for this question.