Which part of the hair is not attached to the follicle?

Correct Answer: C

Rationale: The correct answer is C, 'Shaft.' The hair shaft is the part of the hair that extends above the skin surface and is not attached to the follicle. The bulb and root are parts that are connected to the follicle as they are located below the skin surface and play a role in hair growth. The strand, on the other hand, refers to a single hair fiber and is not a distinct part of the hair anatomy.

Correct Answer: A

Rationale: The correct answer is A: Amygdala. The amygdala is a key brain structure involved in the processing of emotions, including anxiety. Medications for anxiety disorders often target the amygdala to help regulate emotional responses and control anxiety attacks. The amygdala plays a crucial role in the brain's fear circuit and is essential for the appropriate response to stress and threat perception. Choices B, C, and D are incorrect because the parietal lobe is primarily involved in sensory processing and spatial reasoning, the hypothalamus regulates basic functions like hunger, thirst, and body temperature, and sensory neurons transmit signals from sensory receptors to the central nervous system, none of which are directly related to the regulation of anxiety attacks.

Correct Answer: C

Rationale: The correct answer is C: Flexor. A flexor muscle contracts to bend a joint, such as bending the elbow or knee. Flexor muscles are responsible for flexing or bending a joint, while extensor muscles are responsible for extending or straightening a joint. Choice A, Cardiac, is incorrect as cardiac muscle is found in the heart and is responsible for pumping blood. Choice B, Extension, is incorrect as extension refers to the straightening or extending movement of a joint, which is opposite to bending. Choice D, Smooth, is incorrect as smooth muscles are involuntary muscles found in organs like the intestines and blood vessels, not directly responsible for bending joints.

Correct Answer: A

Rationale: The correct answer is A: Embryogenesis. The first trimester of gestation involves the process of embryogenesis, where the basic structures of the embryo are formed. This period is critical for the development of major organ systems and the establishment of the embryo's overall body plan. Fertilization occurs at the beginning of pregnancy when the sperm fertilizes the egg, marking the start of embryonic development. Meiosis is a cell division process that produces gametes (sperm and egg cells) with half the number of chromosomes. Menstruation is the shedding of the uterine lining when pregnancy does not occur.

Correct Answer: B

Rationale: The liver is the organ that compensates when a person's intake of vitamins decreases. It stores certain vitamins, such as vitamins A, D, E, K, and B12, and releases them when dietary intake decreases. This helps maintain the body's vitamin levels and functions. The other organs listed - Appendix, Pancreas, and Stomach - do not primarily play a role in compensating for a decrease in vitamin intake. The liver is crucial in maintaining vitamin balance, making it the correct choice in this context.

Correct Answer: D

Rationale: The correct answer is Oxygen. Oxygen has a total of 8 electrons, with 2 in the first shell and 6 in the second shell. This configuration matches the description provided in the question. Choice A, Beryllium, has 2 electrons in total, so it cannot have 2 in the first shell and 6 in the second. Choice B, Carbon, has 6 electrons in total, so it also does not match the given electron distribution. Choice C, Helium, has only 2 electrons in total and therefore does not fit the electron configuration described in the question.

Correct Answer: D

Rationale: Sucrase is the correct enzyme needed to break down sucrose into its component sugars, glucose, and fructose. Lactase is responsible for breaking down lactose, maltase for maltose, and peptidase for proteins; therefore, they are not the enzymes required to digest sucrose specifically. In the context of digesting birthday cake, which contains sucrose, sucrase is the enzyme needed for this particular sugar.

Correct Answer: B

Rationale: The correct answer is B: Cytoplasm. Pyruvate is a product of glycolysis, a metabolic pathway that takes place in the cytoplasm of the cell. Therefore, a biochemist isolating a large amount of pyruvate would be working with the cytoplasm of the cell. Choice A, Chloroplasts, is incorrect because pyruvate is not produced in chloroplasts, which are responsible for photosynthesis. Choice C, Mitochondria, is incorrect as pyruvate is produced in the cytoplasm before entering the mitochondria for further metabolism. Choice D, Nucleus, is incorrect as the nucleus is not involved in the production or isolation of pyruvate, which is a metabolic intermediate.

Correct Answer: A

Rationale: The correct route of a fetus during childbirth is from the uterus, through the cervix, and then out through the vagina. The contractions of the uterus help push the fetus through the cervix and out through the vaginal canal during childbirth. Choice B is incorrect as it reverses the order of the cervix and uterus. Choice C is incorrect as it includes the vas deferens, which is not part of the female reproductive system. Choice D is incorrect as it lists structures from the female reproductive system but in the wrong order for childbirth.