What is a primer in DNA sequencing?

The correct answer is choice A.

An increase in viscosity of a fluid results in a decrease in mobility of particles.

Viscosity is the resistance of a fluid to a change in shape or movement of neighboring portions relative to one another.

It denotes opposition to flow and may be thought of as internal friction between the molecules.

Choice B is incorrect because an increase in viscosity does not affect the density of a fluid.

Choice C is incorrect because an increase in viscosity results in a decrease, not an increase, in flow rate.

Choice D is incorrect because an increase in viscosity does not affect the pressure of a fluid.

Immunologic memory is the hallmark of adaptive immunity.

Immunologic memory enables the host to mount a more rapid and efficient immune response upon subsequent exposure to the antigen.

Choice A is incorrect because rapid recruitment of immune cells to sites of infection and inflammation is a characteristic of innate immunity.

Choice B is incorrect because antigen-independent defense mechanisms are characteristic of innate immunity.

Choice D is incorrect because non-specific host-defense mechanisms are characteristic of innate immunity.

In a well-designed experiment, all variables apart from the treatment should be kept constant between the control group and treatment group.

This means researchers can correctly measure the entire effect of the treatment without interference from confounding variables.

Choice B) Independent variable and dependent variable is incorrect because these are not groups but rather variables.

The independent variable is manipulated by the experimenters while the dependent variable is measured to see if it changes as a result of the manipulation.

Choice C) Experimental group and non-experimental group is incorrect because a non-experimental group is not a term used in experimental design.

The correct term for the group that does not receive the treatment is control group.

Choice D) High level and low level of the independent variable is incorrect because these are levels of the independent variable, not groups.

In an experiment, there can be multiple levels of the independent variable, but they are applied to different groups (e.g.

control group, treatment group).

Proximal tubule

The proximal tubule is responsible for reabsorbing all the nutrients and most of the water.

Choice A is incorrect because the distal tubule is not primarily responsible for reabsorbing ions, water and nutrients.

Choice C is incorrect because the glomerulus is responsible for filtering fluid and solutes out of the blood to form a glomerular filtrate.

Choice D is incorrect because the Loop of Henle is not primarily responsible for reabsorbing ions, water and nutrients.

The correct answer is choice A.

The shape and surface area of the object.

The terminal velocity of an object falling through a fluid is affected by several factors, including its mass and shape.

Objects with large surface areas will often experience a large amount of air resistance when they move.

Choice B is incorrect because the volume of the object does not affect its terminal velocity.

Choice C is incorrect because the acceleration and momentum of the object do not affect its terminal velocity.

Choice D is incorrect because the height and distance of the fall do not affect the terminal velocity of a falling object.

Atomic mass is very close to mass number but with some deviation in the decimal places.

Atomic mass is also known as atomic weight and is the weighted average mass of an atom of an element based on the relative natural abundance of that element’s isotopes.

The mass number, on the other hand, is a count of the total number of protons and neutrons in an atom’s nucleus.

Choice A is incorrect because atomic mass and mass number do not mean the same thing.

Choice B is incorrect because atomic mass is not always greater than mass number.

Choice C is incorrect because atomic mass and mass number are related.

These are the four nucleotide bases found in DNA1.

Choice B) Adenine, Thymidine, Cytidine, Guanine is incorrect because Thymidine and Cytidine are not nucleotide bases found in DNA.

Choice C) Adenosine, Thymine, Cytosine, Guanosine is incorrect because Adenosine and Guanosine are not nucleotide bases found in DNA.

Choice D) Adenosine, Thymidine, Cytidine, Guanosine is incorrect because Adenosine, Thymidine and Cytidine are not nucleotide bases found in DNA.

The correct answer is choice A.

The superior vena cava is the largest vein in the human body that returns deoxygenated blood from the upper half of the body to the right atrium of the heart.

Choice B is incorrect because the inferior vena cava returns deoxygenated blood from the lower half of the body to the right atrium of the heart.

Choice C is incorrect because the pulmonary vein carries oxygenated blood from the lungs to the left atrium of the heart.

Choice D is incorrect because the renal vein carries deoxygenated blood from the kidneys to the inferior vena cava.

Fertilization.

Fertilization is the process by which male and female gametes fuse to form a zygote.

Oogenesis (choice A) is the process by which female gametes, or eggs, are produced.

Meiosis (choice C) is a type of cell division that results in the formation of gametes.

Mitosis (choice D) is a type of cell division that results in the formation of two identical daughter cells.

Corpus luteum.

During the menstrual cycle, the corpus luteum in the ovary produces progesterone to prepare the endometrium for potential implantation.

Choice B is incorrect because fimbriae are finger-like projections at the end of the fallopian tubes that help guide the egg into the tube.

Choice C is incorrect because a follicle is a sac in the ovary that contains an immature egg.

Choice D is incorrect because the ovarian ligament is a fibrous band of tissue that connects the ovary to the uterus.