Hikers who found a human body at high altitude in the Italian Alps thought the man had died recently, but tests indicated he was shot with an arrow more than 5,300 years ago.

Which of the following would be the best reason for prolonged preservation of the body? .

ff.

In this cross, both parents are homozygous recessive for the smooth leaf trait

(ff).

This means that all of their offspring will inherit two copies of the recessive allele (f) and will therefore have smooth leaves.

Choice A.

FF x FF is not correct because both parents are homozygous dominant for the fuzzy leaf trait (FF) and all of their offspring will inherit two copies of the dominant allele (F) and will therefore have fuzzy leaves.

Choice B.

Ff x Ff is not correct because both parents are heterozygous for the leaf trait (Ff) and their offspring can inherit either one dominant allele (F) or one recessive allele (f) from each parent, resulting in a 3:1 ratio of fuzzy to smooth leaves. Choice D.

Ff x ff is not correct because one parent is heterozygous for the leaf trait (Ff) while the other is homozygous recessive (ff), resulting in a 1:1 ratio of fuzzy to smooth leaves in their offspring.

The atomic number of an element represents the number of protons in the nucleus of an atom of that element.

Since lithium has an atomic number of 3, it has 3 protons in its nucleus.

Choice A is not correct because 7 is the mass number of lithium, not the number of protons.

Choice C is not correct because 12 is not the atomic number or mass number of lithium.

Choice D is not correct because 4 is not the atomic number or mass number of lithium.

The pulmonary veins are the vessels that carry oxygenated blood from the lungs to the left atrium of the heart.

Choice A is not correct because the superior vena cava carries deoxygenated blood from the upper body to the right atrium of the heart.

Choice B is not correct because the inferior vena cava carries deoxygenated blood from the lower body to the right atrium of the heart.

Choice C is not correct because the pulmonary artery carries deoxygenated blood from the right ventricle of the heart to the lungs.

Reverse transcriptase, an enzyme encoded by the virus.

Reverse transcriptase is a virus-specific enzyme that transcribes an RNA template to DNA1.

This allows the AIDS virus, which contains RNA, to insert viral DNA into the DNA of a host cell after the AIDS virus enters the cell.

Choice A, The phospholipids found on the envelope of the virus, is not the correct answer because phospholipids are a major component of cell membranes and do not play a direct role in inserting viral DNA into the DNA of a host cell.

Choice C, Receptor proteins located on the surface of the virus, is not the correct answer because receptor proteins located on the surface of the virus play a role in attachment and fusion of HIV virons to host cells, but do not play a direct role in inserting viral DNA into the DNA of a host cell.

Choice D, The protein that makes up the capsid of the virus, is not the correct answer because capsid is the outer protein shell of a virus and does not play a direct role in inserting viral DNA into the DNA of a host cell.

A tsunami is a catastrophic ocean wave that is usually caused by a submarine earthquake.

It can also be caused by an underwater or coastal landslide, the eruption of a volcano, or the impact of a meteor or comet in a body of water.

Choice A is not correct because sunspot activity does not cause tsunamis.

Choice B is not correct because lightning strikes do not cause tsunamis.

Choice D is not correct because flooding does not cause tsunamis.

Plasma B cells.

Antibodies are produced by specialized white blood cells called B lymphocytes (or B cells).

When an antigen binds to the B-cell surface, it stimulates the B cell to divide and mature into a group of identical cells called a clone.

The mature B cells, called plasma cells, secrete millions of antibodies into the bloodstream and lymphatic system.

Choice A, Natural killer cells, is not the correct answer because natural killer cells are a type of white blood cell that play a major role in the host-rejection of both tumors and virally infected cells.

Choice B, Cytotoxic T-cells, is not the correct answer because cytotoxic T-cells are a type of white blood cell that kills cancer cells, cells that are infected (particularly with viruses), or cells that are damaged in other ways.

Choice D, Helper T-cells, is not the correct answer because helper T-cells are a type of white blood cell that play an important role in the immune system by helping other white blood cells fight infections.

A catalyst is a substance that increases the rate of a chemical reaction without being consumed by the reaction.

As a result, the reaction is completed in a shorter amount of time.

Choice B is not correct because using a catalyst does not necessarily result in the formation of a more desirable product.

Choice C is not correct because using a catalyst does not necessarily result in the release of a greater amount of heat energy by the reaction.

Choice D is not correct because using a catalyst does not necessarily increase the yield of product.

Testosterone is classified as an androgen hormone.

Androgens are a type of sex hormone that primarily regulates the development and maintenance of male characteristics, such as body hair growth, muscle mass, and deepening of the voice.

Testosterone is produced primarily in the testes in males and in smaller amounts in the ovaries and adrenal glands in females.

Option A, estrogen, is a female hormone that regulates the development of female sexual characteristics, such as breast growth and menstruation.

While estrogen and testosterone are both steroid hormones and can be converted to one another in the body, testosterone is not categorized as estrogen.

Option B, progestin, is a synthetic form of the hormone progesterone.

Progesterone is a female hormone that plays a role in the menstrual cycle and pregnancy.

Testosterone and progestin are not related, and testosterone is not categorized as progestin.

Option C, aldosterone, is a mineralocorticoid hormone that regulates salt and water balance in the body.

It is produced in the adrenal gland and plays a role in regulating blood pressure.

Testosterone and aldosterone are not related, and testosterone is not categorized as aldosterone.

The corpus luteum is a structure that develops in the ovary after an egg has been released.

It secretes the hormone progesterone, which prepares the uterus for a fertilized egg to implant and helps maintain the uterine lining during pregnancy1.

Choice A.

Umbilical cord is not correct because it is a structure that connects the developing fetus to the placenta and provides nutrients and oxygen to the fetus, but does not secrete hormones.

Choice C.

Oviduct is not correct because it is a tube that transports eggs from the ovary to the uterus, but does not secrete hormones.

Choice D.

Oocyte is not correct because it is an immature egg cell, but does not secrete hormones.

The hypothalamus is a region of the brain that synthesizes antidiuretic hormone (ADH), also known as vasopressin.

ADH is then transported to the posterior pituitary gland via neurohypophysial capillaries, where it is stored until it is ready to be secreted into the circulation.

Choice A.

Pineal gland is not correct because it is a small endocrine gland located in the brain that secretes the hormone melatonin, which regulates sleep-wake cycles, but it does not synthesize ADH.

Choice B.

Thymus is not correct because it is a gland located in the chest that produces hormones involved in immune system development, but it does not synthesize ADH.

Choice D.

Pancreas is not correct because it is a gland located behind the stomach that secretes hormones such as insulin and glucagon, which regulate blood sugar levels, but it does not synthesize ADH.