Which of the following processes causes most of the carbon dioxide from the blood to move into the alveoli?

 

The atomic number of an atom is equal to the number of protons in its nucleus.

In this case, the atom has 12 protons, so its atomic number is 12.

Choice A, 24, is not the correct answer because it represents the sum of the number of protons and neutrons in the atom’s nucleus, which is known as the mass number.

Choice C, 1, is not the correct answer because it does not represent the number of protons in the atom’s nucleus.

Choice D, 144, is not the correct answer because it represents the square of the mass number and does not represent any property of the atom.

Osmosis is the movement of water molecules across a selectively permeable membrane from an area of higher water concentration to an area of lower water concentration.

In a hypertonic solution, the concentration of solutes outside the cell is higher than inside the cell, so water flows out of the cell through aquaporins embedded in the plasma membrane to balance the concentration gradient.

Choice A.

Facilitated diffusion is not correct because it is a type of passive transport that involves the movement of molecules across a membrane through specific transport proteins, but it does not specifically refer to the movement of water molecules.

Choice B.

Active transport is not correct because it is a type of transport that involves the movement of molecules against their concentration gradient and requires energy in the form of ATP, but osmosis is a passive process that does not require energy.

Choice D.

Diffusion is not correct because it refers to the movement of molecules from an area of higher concentration to an area of lower concentration, but it does not specifically refer to the movement of water molecules.

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 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.

A myocardial infarction affects the coronary blood vessels of the heart.

A myocardial infarction, commonly known as a heart attack, occurs when blood flow decreases or stops in the coronary artery of the heart, causing damage to the heart muscle 1.

Choice B is incorrect because the aorta is not a blood vessel of the heart.

The aorta is the main artery that carries oxygenated blood from the heart to the rest of the body.

Choice C is incorrect because the pulmonary blood vessels are not affected by a myocardial infarction.

The pulmonary blood vessels carry deoxygenated blood from the heart to the lungs.

Choice D is incorrect because the vena cava is not a blood vessel of the heart.

The vena cava is a large vein that carries deoxygenated blood from the body to the heart.

The approximate threshold value for mammalian neurons is -55 mV.

The threshold potential is the critical level to which a membrane potential must be depolarized to initiate an action potential.

Most often, the threshold potential is a membrane potential value between –50 and –55 mV

The membrane potential of a neuron is determined by the distribution of ions across the cell membrane.

At rest, the inside of a neuron is more negative than the outside due to the presence of negatively charged proteins and other molecules.

The movement of ions across the cell membrane can change the membrane potential.

For example, when sodium ions enter the cell, they make the inside of the cell more positive (less negative), causing depolarization.

Choice B is incorrect because -80 mV is below the typical threshold value for mammalian neurons.

Choice C is incorrect because +35 mV is above the typical threshold value for mammalian neurons.

Choice D is incorrect because 0 mV is above the typical threshold value for mammalian neurons.

Viruses.

Viruses lack essential machinery needed to reproduce by themselves.

In fact, viruses can only reproduce after infecting a living cell - a process called viral replication.

Once inside a living cell, viruses re-program the cell’s machinery to produce viral proteins and genetic material to make new copies of themselves.

Choice A, Bacteria, is not the correct answer because bacteria have their own metabolic pathways and can reproduce outside of a host cell.

Choice B, Protozoa, is also not the correct answer because protozoa are singlecelled eukaryotes that have their own metabolic pathways and can reproduce outside of a host cell.

Choice C, Helminths, is not the correct answer because helminths are multicellular parasitic worms that have their own metabolic pathways and can reproduce outside 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.

Triple covalent bonds.

Nitrogen gas (N2) is an extremely stable molecule because it consists of two nitrogen atoms bonded together by a triple covalent bond.

A covalent bond is a type of chemical bond where atoms share electrons to form a molecule.

In a triple covalent bond, three pairs of electrons are shared between the two atoms, resulting in a very strong bond that makes the molecule extremely stable.

Choice A.

Ionic bonds is not correct because ionic bonds involve the transfer of electrons from one atom to another to form ions, which are then attracted to each other due to their opposite charges.

Nitrogen gas does not contain ions and is not held together by ionic bonds.

Choice B.

Hydrogen bonds is not correct because hydrogen bonds are weak electrostatic attractions between molecules that contain hydrogen atoms bonded to highly electronegative atoms such as oxygen or nitrogen.

Nitrogen gas does not contain hydrogen atoms and is not held together by hydrogen bonds.

Choice C.

Resonance bonds is not correct because resonance refers to the delocalization of electrons in a molecule where multiple Lewis structures can be drawn to represent the molecule.

Nitrogen gas has a single Lewis structure and does not exhibit resonance.

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.