Systems Biology - GED Science

Card 0 of 130

Question

What is the name of the process by which food is moved through the esophagus via a wave-like contracting motion?

Answer

The esophagus assists moving food into the stomach using a wave-like contracting motion called peristalsis. Swallowing initiates the process of peristalsis, but unlike swallowing, peristaltic contractions are not voluntary and are generated by smooth muscle.

Mastication is another term for "chewing." Emulsification refers to the grouping together of fat molecules when in an aqueous environment, particularly during digestion in the small intestine.

Compare your answer with the correct one above

Question

Which part of the digestive system does not contribute to the chemical digestion of food?

Answer

Food is digested to some degree in many different parts of the digestive system. The mouth, stomach, and small intestine all contribute to food digestion. The mouth contains salivary amylase, which breaks down carbohydrates. The stomach contains pepsin, which breaks down proteins. The small intestine contains several enzymes, such as lipase and trypsin, and breaks down carbohydrates, lipids, and proteins.

The esophagus, however, does not contribute to chemical digestion in any way.

Compare your answer with the correct one above

Question

What is the role of bile in digestion?

Answer

Bile is created by the liver and released into the small intestine from the gall bladder during digestion. Because fat tends to clump in the aqueous environment of the duodenum, bile helps to increase the surface area of fat, a process called emulsification. This helps lipase break down the fats adequately.

Compare your answer with the correct one above

Question

What class of hormone must attach to membrane-bound receptors?

Answer

There are three primary types of hormones: peptide hormones, steroid hormones, and tyrosine derivative hormones. Of the three, peptide hormones are the only polar hormones, so they cannot pass the cell membrane. As a result, they must attach to a membrane-bound receptor in order to elicit a response in the cell.

Tyrosine derivatives and steroid hormones are smaller, nonpolar molecules. This allows them to pass directly through the membrane, rather than binding to a receptor on the surface. Steroid hormones are derived from cholesterol, but there is no such thing as "cholesterol hormones."

Compare your answer with the correct one above

Question

Which of the following is a steroid hormone?

Answer

Steroid hormones are created in the gonads and the adrenal cortex. They include testosterone, estrogen, cortisol, aldosterone, and progesterone.

Human growth hormone, oxytocin, and insulin are all peptide hormones, meaning that they are proteins made of amino acids. In contrast, steroid hormones are derived from cholesterol and have distinct ring structures.

Compare your answer with the correct one above

Question

What hormone is responsible for lowering blood sugar levels in the body?

Answer

Managing blood sugar levels is primarily the responsibility of the pancreatic hormones glucagon and insulin. Glucagon is responsible for raising blood sugar levels while insulin helps reduce the sugar levels.

Oxytocin is a hormone secreted from the posterior pituitary gland; it induces labor and contractions during childbirth. Thyroxine (also known as thyroid hormone or T4) is secreted from the thyroid and helps regulate metabolism.

Compare your answer with the correct one above

Question

Which hormone is NOT created in the pituitary gland?

Answer

The pituitary gland is responsible for a number of peptide hormones, including follicle-stimulating hormone, thyroid-stimulating hormone, and prolactin. Aldosterone, however, is produced in the adrenal cortex and functions to raise blood pressure by preventing fluid loss via urination.

Compare your answer with the correct one above

Question

Which cell type secretes antibodies that attach to pathogens in the body?

Answer

B-cell lymphocytes are responsible for the production of antibodies. These white blood cells secrete antibodies, which bind to and promote the destruction of pathogens

Macrophages attack pathogens directly. T-cell lymphocytes can help attack pathogens as well, and can also trigger B-cells to release antibodies. Red blood cells (erythrocytes) are not involved in the immune response.

Compare your answer with the correct one above

Question

What blood type could not be given to a person with type A blood in a transfusion?

Answer

When it comes to blood type, the type of blood you have is determined by the type of antigens present on your red blood cells. For example, people with type A blood have the A antigen on their red blood cells, but not the B antigen. People with O blood have no antigens on their red blood cells. The immune system of a person with A blood will respond negatively to B blood if it is introduced into the body.

A person with type A blood could receive type A blood (A antigens) or type O blood (no antigens), but could not receive type B blood (B antigens) or type AB blood (A and B antigens).

Compare your answer with the correct one above

Question

What is the function of the innate immune system?

Answer

Your innate immunity is the generalized system responsible for first attacking incoming infectious agents and toxins. Innate means that it is not necessary to have previously seen the pathogen, and the body always has these general defense mechanisms. Macrophages, neutrophils, and basophils are some of the primary cell types of innate immunity.

In contrast, the adaptive immune system is only effective against pathogens that have previously entered the body. A previous infection will result in the body producing antibodies during any later infections. T-cells and B-cells (lymphocytes) are the primary cell types of adaptive immunity.

Compare your answer with the correct one above

Question

What structure is responsible for connecting a muscle to a bone?

Answer

Muscles do not attach directly to bones. Instead, a tendon is used to attach the two structures. Ligaments connect a bone to another bone, while joints are the locations where bones move around one another.

Compare your answer with the correct one above

Question

Which type of muscle is under voluntary control?

Answer

There are three types of muscle in the body: skeletal, cardiac, and smooth muscle. Of the three, skeletal muscle is the only one that can be consciously controlled. Cardiac and smooth muscle are controlled involuntarily.

An example of skeletal muscle is your biceps brachii muscle; you can voluntarily control this muscle to flex your arm. An example of smooth muscle is the muscle surrounding your arteries; you cannot voluntarily contract this muscle to constrict your arteries. Cardiac muscle is found in the heart; you cannot voluntarily choose to slow your heart rate.

Compare your answer with the correct one above

Question

What is one function of bone marrow?

Answer

Red bone marrow is found in the ends (epiphyses) of long bones such as the femur and is responsible for red blood cell development. Yellow bone marrow is found in the center (diaphysis) of long bones and can store fat for energy.

Blood filtration primarily occurs in the spleen or kidney. Glycogen is primarily stored in the liver. Calcium is released from the mineral matrix of the bone, but is not actually found in the bone marrow.

Compare your answer with the correct one above

Question

How does cardiac muscle differ from skeletal muscle?

Answer

Skeletal and cardiac muscle have quite a bit in common: both are examples of striated muscle that use the sarcomere as the basic functional unit. Sarcomeres are small units that are capable of contracting. When these units line up in a cell, they create a striped appearance known as "striated" or "striations." Both skeletal and cardiac muscle are capable of contracting; this is a key characteristic of any muscle cell.

A primary difference between skeletal and cardiac muscle cells is the number of nuclei each cell possesses. Skeletal muscle cells usually have several nuclei, but cardiac muscle cells usually have only one nucleus per cell.

Compare your answer with the correct one above

Question

Which of the following cells only contains a single copy of each chromosome?

Answer

The germ cells (eggs/oocytes and sperm) contain only one copy of each chromosome. This reduction in the amount of DNA occurs through meiosis. Most cells in the body contain two copies of each chromosome and are considered diploid. Since they only contain ne copy of each chromosome, germ cells are considered haploid.

Neurons and lymphocytes (white blood cells) contain two copies of each chromosome; they are diploid. Erythrocytes (red blood cells) do not have nuclei, and do not contain any genetic material.

Compare your answer with the correct one above

Question

What event in females precedes the egg being released from the follicle?

Answer

Ovulation, or the release of the egg from its follicle, is initiated by a temporary spike in estradiol (estrogen) levels. This positive feedback event is referred to as the luteal surge.

Menstruation follows ovulation. Gastrulation is a phase of development during which the primary germ layers are generated in an embryo, and is not related to the female cycle.

Compare your answer with the correct one above

Question

The heart, which is responsible for pumping oxygenated blood throughout the body, is a component of which system?

Answer

The circulatory system is responsible for transporting blood, oxygen, nutrients, and wastes throughout the body. The vessels of the circulatory system include arteries, arterioles, capillaries, venules, and veins. The heart is responsible for pumping the fluids of the circulatory system through these vessels, and is a major component of the circulatory system.

The respiratory system is responsible for transporting air to and from the lungs, and facilitates gas exchange with the capillaries of the circulatory system. The lymphatic system helps regulate fluid balance and immune system function; it consists of lymphatic vessels, the spleen, and the thymus. The digestive system breaks down and absorbs nutrients; it consists of the digestive tract from the mouth, through the stomach and small intestine, and to the rectum.

Compare your answer with the correct one above

Question

Which heart chamber pumps blood to the body's tissues?

Answer

The heart has four chambers: two atria and two ventricles. The atria are responsible for receiving blood returning from the body, while the ventricles pump blood out of the heart. The right ventricle pumps blood to the lungs, while the left ventricle pumps blood to the rest of the body.

The flow of blood through the heart is: right atrium, right ventricle, lungs, left atrium, left ventricle, body.

Compare your answer with the correct one above

Question

Which of the following statements is true about arteries?

Answer

Arteries are the high pressure blood vessels responsible for carrying blood away from the heart. All arteries in the body travel away from the heart toward other tissues.

Most arteries carry oxygenated blood, but the pulmonary arteries carry deoxygenated blood; these vessels are responsible for transporting deoxygenated blood from the right side of the heart to the lungs. Veins are responsible for returning blood back to the heart. Arteries do not allow for diffusion of nutrients; this process primarily occurs in capillaries.

Compare your answer with the correct one above

Question

Which statement about the heart is true?

Answer

The heart is able to pump independently of the brain thanks to a collection of cells that fire impulses automatically. These cells are located in the sinoatrial node, which leads to the node's nickname as the "pacemaker" of the heart. Even without stimulation by a nerve, the heart can continue beating.

The heart is made of cardiac muscle tissue; smooth muscle tissue lines internal organs and blood vessels. Both sides of the heart pump at the same rate, but the left side pumps with more force. Each side of the heart must pump the same volume, but the left side must pump it a greater distance since it pushes blood to the entire body. A normal resting heart rate is around 60-80 beats per minute. A heart rate of 120 would be more typical during exercise.

Compare your answer with the correct one above

Tap the card to reveal the answer