Which biological process is represented in the diagram below?

Substance X directly supplies energy for various life functions, as shown in the diagram below. Which substance is represented by X in the diagram?

The structural formulas shown below represent parts of two different complex carbohydrate molecules composed of glucose subunits. Molecules 1 and 2 differ in their overall structure. Due to the differences in structure, each of these molecules most likely

To capture their prey, spiders have fangs, which pierce the body wall of insects and inject venom. Spider venoms usually contain specific proteins that attack the cell membranes of the prey. The membranes and most of the contents of the insect’s body turn into a liquid that the spider then ingests for food. These specific venom proteins are most likely

Lymphatic capillaries are found throughout the body. Both the lymphatic and circulatory systems transport substances between the bloodstream and body tissues. These two systems are also involved in fighting infections. The arrows shown in the diagram that go from the blood capillaries to the interstitial fluid most likely represent the

Doctors often use certain medications to treat infections. A few people have a reaction to some of these medications, such as itching, swelling, or trouble breathing. This is an example of

A small lizard spends the morning hours lying in the sunlight until its body temperature rises. Later on in the day, the lizard rests in a shady area until its body temperature cools. This type of behavior is important to

The Venus flytrap is a plant that has a unique system by which it traps and breaks down its prey. Unsuspecting insects land on the leaf and touch tiny hairs located on the leaf, triggering the leaf to close around the prey. The substance responsible for breaking down the Venus flytrap’s prey most likely contains

It may be harmful when people compete to see who can hold their breath the longest under water. Without oxygen, brain cells

Students did an experiment comparing the activity of four different enzymes, A, B, C, and D. The results are represented in the graph below. A valid conclusion based on the information in the graph is that

The diagram below represents changes that take place within the human body. The diagram represents

Sailors in the past may have heard the greeting from a passing ship, “Avast ye scurvy dogs.” This greeting would be a reference to a disease known as scurvy, which is due to inadequate intake of vitamin C. Which row in the chart below correctly identifies the cause of this disease and a possible treatment for it?

In the 1660s, Flemish physician Jan van Helmont grew a small willow tree in a pot of soil. He added only water to the pot. At the end of five years, he found that the tree had gained 75 kilograms, but there was very little change in the mass of the soil. Van Helmont concluded that the plant gained weight directly from the water. We now know that this conclusion is only partially correct because, in addition to water, photosynthesis also requires

Doctors sometimes use a vaccine to prepare the body to defend itself against future infections. These vaccines most often contain

Anhidrosis is the inability to sweat normally. If the human body cannot sweat properly, it cannot cool itself, which is potentially harmful. Anhidrosis most directly interferes with

Carmine, a compound that comes from the cochineal beetle, shown below, is used as a food coloring. The food coloring is not harmful to most people, but in a small number of individuals, it causes a reaction and affects their ability to breathe. This response to carmine is known as