TEAS 7 science study guide free

Correct Answer: B

Rationale: Glucagon is the correct answer. Produced by the pancreas, glucagon acts in opposition to insulin by increasing blood sugar levels. Glucagon promotes the breakdown of glycogen into glucose in the liver, leading to the release of glucose into the bloodstream. Insulin, on the other hand, lowers blood sugar levels by facilitating the uptake of glucose into cells. Cortisol is a hormone produced by the adrenal glands, not the pancreas, and is involved in stress response and metabolism. Thyroxine is a hormone produced by the thyroid gland and is primarily responsible for regulating metabolism.

Correct Answer: B

Rationale: The correct answer is B. CRISPR-Cas9 technology allows precise editing of germline cells, raising ethical concerns about modifying the human gene pool. This includes potential eugenic implications, debates on altering future generations, and the moral implications of such genetic modifications. Choice A discusses unintended consequences and off-target effects, but the primary ethical consideration with CRISPR-Cas9 technology relates to altering the human germline. Choices C and D, while important factors, are not the central ethical dilemmas associated with using CRISPR-Cas9 technology in humans.

Correct Answer: B

Rationale: The number of protons in an atom is known as the atomic number. The atomic number uniquely identifies an element and determines its position on the periodic table. It is a fundamental property of an element and directly influences its chemical behavior and interactions. The mass number, on the other hand, is the sum of protons and neutrons in the nucleus of an atom, not just protons. Atomic weight is the average mass of an element's isotopes considering their relative abundance, not solely based on the number of protons. Valence electron count refers to the number of electrons in the outermost energy level of an atom, influencing its ability to form bonds and participate in chemical reactions, but it is not determined by the number of protons in the atom.

Correct Answer: B

Rationale: The correct answer is B, the menstrual cycle. The menstrual cycle is the monthly series of changes that occur in the female reproductive system, preparing the body for potential pregnancy. One of the key events in this cycle is the thickening of the uterine lining in anticipation of receiving a fertilized egg. If fertilization does not occur, this thickened lining is shed during menstruation. Choices A, C, and D are incorrect. The ovulation cycle specifically refers to the release of the egg from the ovary, not the entire monthly reproductive cycle. The implantation cycle is the phase when a fertilized egg attaches to the uterine lining, not the overall monthly cycle. The gestation cycle pertains to the period of development from conception to birth, not the cycle preparing for potential pregnancy.

Correct Answer: B

Rationale: Proteins require the most complex and lengthy digestion process compared to the other nutrient types provided. When proteins are consumed, they undergo a process where they need to be broken down into amino acids, which are essential building blocks of proteins. This intricate digestion process begins in the stomach aided by stomach acid and enzymes, proceeds to the small intestine where further enzymes break down proteins into amino acids, and concludes with the absorption of these amino acids into the bloodstream for various bodily functions. Carbohydrates and fats also require digestion, but the process for breaking down proteins into amino acids is notably more intricate and time-consuming. In contrast, vitamins do not require digestion in the same manner as proteins, carbohydrates, and fats because they are already in a form that can be readily absorbed by the body.