TEAS 7 Biology: Master Key Concepts

ATI TEAS 7

Biology

1. Which of the following is NOT a primary producer in an ecosystem?

A. Grass
B. Deer
C. Algae
D. Mushroom

Correct answer: B

Rationale: Rationale: - A) Grass: Grass is a primary producer because it can photosynthesize and convert sunlight into energy, making it the base of the food chain. - B) Deer: Deer are consumers that feed on primary producers like grass, so they are not primary producers themselves. - C) Algae: Algae are primary producers that can photosynthesize and produce energy from sunlight. - D) Mushroom: Mushrooms are decomposers that break down organic matter, so they are not primary producers.

2. Imagine you have an element with atomic number 11 and mass number 23. How many neutrons does it have?

A. 11
B. 12
C. 23
D. Cannot be determined without additional information

Correct answer: B

Rationale: Rationale: - The atomic number (Z) of an element is the number of protons in its nucleus. In this case, the element has an atomic number of 11. - The mass number (A) of an element is the sum of its protons and neutrons. Given that the mass number is 23 and the atomic number is 11, we can calculate the number of neutrons by subtracting the atomic number from the mass number: Neutrons = Mass number - Atomic number = 23 - 11 = 12. - Therefore, the element with atomic number 11 and mass number 23 has 12 neutrons.

3. A balanced chemical equation for the reaction between sodium and chlorine to form sodium chloride is:

A. Na + Cl2 -> NaCl
B. 2Na + Cl2 -> 2NaCl
C. Na2 + Cl -> 2NaCl
D. Na + 2Cl -> NaCl2

Correct answer: A

Rationale: The correct balanced chemical equation for the reaction between sodium and chlorine to form sodium chloride is '2Na + Cl2 -> 2NaCl'. This equation is balanced as it shows that 2 atoms of sodium react with 1 molecule of chlorine gas to produce 2 molecules of sodium chloride. Option A 'Na + Cl2 -> NaCl' is incorrect as it does not balance the number of atoms on both sides of the equation. It only shows 1 atom of sodium reacting with 1 molecule of chlorine, which is not a balanced representation of the chemical reaction. Therefore, option B is the correct choice for this question.

4. Which hormone, produced by the ovaries, is responsible for the development of the uterine lining during the menstrual cycle and supports early pregnancy?

A. Estrogen
B. Progesterone
C. Testosterone
D. Prolactin

Correct answer: B

Rationale: The correct answer is B: Progesterone. Progesterone is a hormone produced by the ovaries that plays a crucial role in the menstrual cycle and early pregnancy. During the menstrual cycle, progesterone helps to prepare the uterine lining for a potential pregnancy by making it thick and vascularized. If fertilization occurs, progesterone continues to support the early stages of pregnancy by maintaining the uterine lining and preventing menstruation. Estrogen also plays a role in the menstrual cycle by stimulating the growth of the uterine lining, but progesterone is primarily responsible for maintaining the uterine environment suitable for implantation and supporting early pregnancy. Testosterone is a male sex hormone, while prolactin is a hormone involved in milk production after childbirth.

5. Deuterium, a stable isotope of hydrogen, has a nucleus containing:

A. A single proton
B. A proton and a neutron
C. Two protons and an electron
D. Two neutrons

Correct answer: B

Rationale: The correct answer is B: 'A proton and a neutron.' Deuterium is an isotope of hydrogen with an atomic number of 1, meaning it has 1 proton in its nucleus. However, deuterium also has a neutron in its nucleus, making it different from regular hydrogen which only has a proton in its nucleus. Therefore, deuterium has a nucleus containing both a proton and a neutron, making option B the correct choice.