Unit 7

Multiple Choice
Identify the choice that best completes the statement or answers the question.

____	1.	Which of the following best describes the main function of the circulatory system?
A.	to deliver nutrients and other essential materials to cells and remove waste products	
B.	to break down the nutrients found in food so that they can be used by all cells in the body	
C.	to produce the chemical signals that allow parts of the body to communicate over long distances	
D.	to coordinate all other body systems so that they can function together to maintain homeostasis	

____	2.	Which of the following includes three parts of the cardiovascular system?
A.	the lungs, the heart, and the brain	
B.	the blood, the spleen, and the tonsils	
C.	the heart, the arteries, and the capillaries	
D.	the veins, the lymph nodes, and the thymus	

____	3.	Ahmed is studying certain blood vessels in the body. In these vessels, blood travels from the heart to the muscles in the upper arms. Which type of vessels is Ahmed studying?
A.	veins 	
B.	arteries	
C.	capillaries	
D.	lymph ducts	

____	4.	Which of the following includes two types of cells found in blood?
A.	platelets and capillaries	
B.	red blood cells and antigens	
C.	red blood cells and capillaries	
D.	white blood cells and platelets	

____	5.	Which of the following best describes lymph fluid?
A.	a fluid that builds up in sinuses	
B.	a fluid that surrounds the cells of the human body	
C.	a fluid that contains red cells, white cells, and platelets	
D.	a fluid found in the mouth that contains digestive enzymes 	

____	6.	The circulatory system is made up of parts that work together. Look at the following diagram, which shows part of this system. 

What is the function of the structures labeled 1?

A.	to produce the lymph fluid needed by the body	
B.	to remove pathogens and dead cells from the lymph fluid	
C.	to produce the cells needed to fight infections in the body	
D.	to remove carbon dioxide and other wastes from the lymph fluid	

____	7.	Which statement is true of the lymphatic system?
A.	The thymus is a gland near the heart that produces T cells. 	
B.	The spleen is the substance inside the bones that filters blood.	
C.	The tonsils are muscular organs in the throat that produce antigens.	
D.	The lymph nodes are structures that produce lymphocytes to fight infections. 	

____	8.	Which process best describes respiration?
A.	removing wastes from the blood stream	
B.	breaking down food into smaller nutrients	
C.	obtaining oxygen and releasing carbon dioxide	
D.	eliminating pathogens from the blood and lymph fluid	

____	9.	Amy goes to the doctor because she is not feeling well. The doctor carefully looks for anything abnormal in Amy’s pharynx. The doctor then listens through his stethoscope for abnormal sounds in Amy’s bronchi and alveoli. Which body system is the doctor examining?
A.	the lymphatic system	
B.	the respiratory system	
C.	the circulatory system	
D.	the cardiovascular system	

____	10.	Read the following two statements:

       I. This is a single tube that connects the larynx to the lungs.
      II. This is one of two tubes that connects the trachea to the lungs.

Which of the following is true?
A.	Statement I refers to the trachea.	
B.	Statement I refers to the bronchi.	
C.	Statement II refers to the alveoli.	
D.	Statement II refers to the pharynx. 	

____	11.	Which statement correctly describes a difference between the pharynx and the larynx?
A.	The pharynx contains the vocal cords; the larynx does not.	
B.	The pharynx is closer to the mouth; the larynx is closer to the lungs.  	
C.	The larynx is a single tube; the pharynx includes two parallel tubes.	
D.	The larynx is larger than the pharynx; the pharynx is a small part of the larynx.	

____	12.	What is the main function of the digestive system?
A.	to remove wastes found in the blood	
B.	to break down food so that it can be used by the body	
C.	to transport important nutrients to all parts of the body	
D.	to communicate signals between distant parts of the body	

____	13.	When he eats, Eli takes his time and chews his food carefully. Which of these explains what Eli is doing as his teeth mash and crush the food into small pieces?
A.	He is performing peristalsis. 	
B.	He is chemically digesting his food.	
C.	He is mechanically digesting his food.	
D.	He is mixing his saliva with bile.	

____	14.	Lipase is an enzyme that breaks down the fat in food molecules into smaller molecules. Which of the following best describes the function of lipase?
A.	absorption	
B.	indigestion	
C.	chemical digestion	
D.	mechanical digestion	

____	15.	Alice feels pain in her chest after she eats a big meal. Her doctor tells her that the pain is from stomach acid being pushed up into the tube that leads from her mouth to her stomach. To which digestive system structure is Alice’s doctor referring?
A.	liver	
B.	esophagus	
C.	large intestine	
D.	small intestine	

____	16.	Which term refers to the muscular contractions that push food through such organs as the esophagus and the intestines? 
A.	absorption	
B.	digestion	
C.	enzymes	
D.	peristalsis	

____	17.	Sofia finds a diagram, similar to the one that follows, that shows what the inside of a human small intestine looks like. She notices that the inside of this organ is covered with small, fingerlike projections.

What are these projections called?

A.	bile	
B.	enzymes	
C.	nephrons	
D.	villi	

____	18.	What is the main function of the small intestine?
A.	to mechanically break down food into tiny pieces	
B.	to produce bile that breaks down proteins in food	
C.	to store waste before it is eliminated from the body	
D.	to absorb the nutrients from food into the bloodstream	

____	19.	Pierre is studying the organs in the human digestive system. He looks at a diagram of the 
intestines, similar to the one that follows. 

Which of the following correctly describes the diagram?
A.	Structure A is the small intestine, and structure B connects the mouth to the stomach.	
B.	Structure A is the small intestine, and structure B absorbs water from digested material.	
C.	Structure A is the large intestine, and structure B absorbs nutrients from digested material. 	
D.	Structure A is the large intestine, and structure B produces bile and stores it temporarily. 	

____	20.	Juan goes to see his doctor because his stomach has been bothering him. The doctor tells Juan that the problem is not actually with his digestive system, but is with the body system that regulates and controls the digestive system. To which body system is the doctor referring?
A.	circulatory 	
B.	excretory 	
C.	nervous 	
D.	respiratory 	

____	21.	What is the main function of the excretory system?
A.	to remove waste from the blood	
B.	to regulate and control other body systems	
C.	to obtain oxygen and transport it to all tissues	
D.	to break down nutrients into smaller molecules	

____	22.	Some diseases cause a person’s kidneys to not function properly. A dialysis machine is a device that does the work of a person’s kidneys. What does a dialysis machine do? 
A.	break down nutrients 	
B.	filter waste from the blood	
C.	regulate the digestive system 	
D.	transport oxygen through the bloodstream	

____	23.	A ureter carries liquid waste between which structures?
A.	a kidney and the bladder	
B.	a nephron and a kidney	
C.	a glomerulus and a nephron	
D.	the bladder and the outside of the body	

____	24.	How do a ureter and a nephron differ?
A.	A ureter filters blood, but a nephron only transports blood.	
B.	A ureter transports liquid waste, but a nephron transports blood. 	
C.	A ureter is inside a kidney, but a nephron is connected to the outside of a kidney. 	
D.	A ureter is connected to the outside of a kidney, but a nephron is inside a kidney.	

____	25.	After being lost for many hours on a hot day during a hiking trip, Soren becomes severely dehydrated. Which of the following describes an effect dehydration could have on his body? 
A.	His kidneys will have to work extra hard because they maintain water balance in the body. 	
B.	His bladder will have to work extra hard to prevent extra liquid waste from entering a glomerulus. 	
C.	His ureters will have to work extra hard to carry more waste from his bladder to his kidneys.	
D.	His nephrons will have to work extra hard to transport liquid waste from his ureters to his urethra.	

____	26.	Which is the main control center of the nervous system?
A.	brain	
B.	heart	
C.	medulla	
D.	spinal cord	

____	27.	How are axons similar to dendrites?

A.	They both are about the same length. 	
B.	They are both needed for a neuron to work.	
C.	They both send chemical signals to other cells.	
D.	They both receive information from other cells.	

____	28.	How does the structure of dendrites relate to their function in the nervous system?
A.	Their connective tissue helps hold them together in bundles to make nerves.	
B.	Their length allows nerve impulses to travel long distances through the body.	
C.	Their branched structure allows them to receive signals from many nerve cells. 	
D.	Their terminal end allows them to send chemical signals to other types of cells. 	

____	29.	When you are listening to someone and talking to him or her, which part(s) of the brain control your actions?
A.	the medulla and the cerebellum 	
B.	the cerebrum and the spinal cord 	
C.	the left hemisphere of the cerebrum 	
D.	the right hemisphere of the cerebellum	

____	30.	Many disorders can affect the nervous system. These disorders can happen when parts of the nervous system are damaged by disease or injuries. They can result in problems with balance and movement and other symptoms. Which of the following disorders does not affect the nervous system?
A.	multiple sclerosis	
B.	spinal cord injuries	
C.	rheumatoid arthritis 	
D.	Parkinson’s disease	

____	31.	What are hormones?
A.	specialized cells that destroy bacteria and viruses 	
B.	specialized cells that control growth and metabolism	
C.	chemical messengers that are produced in bone marrow that are used to control body functions	
D.	chemical messengers that are produced in one type of tissue and cause changes in another type of tissue	

____	32.	The body must maintain a relatively stable amount of sugar in the blood to work properly. How would the endocrine system respond after a person digests a piece of fruit?
A.	It will remove waste less quickly from the blood. 	
B.	It will remove waste more quickly from the blood.  	
C.	It will release less of the hormone that helps cells take glucose out of the blood.	
D.	It will release more of the hormone that helps cells take glucose out of the blood.	

____	33.	It is important for conditions inside the body to be stable as the external environment changes. The endocrine system helps the body do this through feedback mechanisms. What is the endocrine system feedback mechanism?

A.	an involuntary reaction that controls the way an organ works 	
B.	a way to remove waste in response to more food being digested	
C.	a change in the amount of hormones regulating the amounts of chemicals in cells	
D.	an increase in electrical signals from the nerves that increase the response of tissues	

____	34.	Hearing is one of the major senses. The following diagram shows the main parts of a human ear.

What is the purpose of the structures of the middle ear shown in the diagram?

A.	They transfer sound energy to the inner ear.	
B.	They change their positions to help maintain balance.  	
C.	They produce sound waves when light energy enters the ear.	
D.	They decrease the energy of sound waves to help prevent injury. 	

____	35.	Which is a group of cells that produces chemicals and secretes them into the bloodstream?
A.	gland 	
B.	hormone	
C.	neuron 	
D.	receptor	

____	36.	Qi has recorded her height every year since she was 9 y old. She made a bar graph to see how her height changed during that time.

What can you conclude about her glands from this chart?

A.	Her pancreas was producing insulin to regulate her growth.	
B.	Her pituitary gland was making hormones that caused her to grow. 	
C.	Her thymus gland was making hormones to control her growth rate. 	
D.	Her pineal gland was producing hormones that increased her digestion.	

____	37.	The hypothalamus is part of the brain. The pituitary gland is near the hypothalamus. The diagram shows the location of these structures in the body. 

Which two structures shown work together to help regulate body systems?

A.	The hypothalamus uses information from the brain to control the pituitary gland. 	
B.	The pituitary gland sends information to the hypothalamus to control the brain. 	
C.	The hypothalamus produces hormones that control all glands, including the pituitary gland. 	
D.	The pituitary gland and the thyroid gland are the only glands that send hormones throughout the body. 	

____	38.	The hormone estrogen triggers sexual development in females. Which of the following changes takes place during this stage of life?

A.	A girl’s hips narrow.	
B.	A girl begins to menstruate.	
C.	A girl gains muscle coordination.	
D.	A girl’s oil glands become less active.	

____	39.	The male reproductive system produces sperm. The following image shows the parts of the male reproductive system.

What are the name and function of part 5 of the male reproductive system?

A.	penis; delivers sperm	
B.	testes; make sperm cells	
C.	vas deferens; stores sperm	
D.	urethra; connects epididymis and urethra	

____	40.	For females, at what age does puberty usually arrive?

A.	before age 10	
B.	around age 51	
C.	between ages 10 and 15	
D.	between ages 40 and 50	

____	41.	What is the average length of menstruation in days?

A.	1–2 days	
B.	4–5 days	
C.	5–6 days	
D.	6–7 days	

____	42.	Several sperm cells at once may reach and try to enter an egg cell. The following image shows sperm cells approaching an egg cell.

What happens after Sperm B completes Step 2?

A.	Sperm B will duplicate itself.	
B.	Sperm A and Sperm C will also enter the egg.	
C.	Sperm A and Sperm C will search for a different egg.	
D.	The egg prevents Sperm A and Sperm C from entering.	

____	43.	Which of the following sexually transmitted infections is caused by HIV?

A.	AIDS	
B.	hepatitis	
C.	herpes	
D.	HPV	

____	44.	After the first 8 weeks of pregnancy, an embryo is about 3 cm long. For the remaining approximately 31 weeks of pregnancy, what is an embryo called?

A.	embryo	
B.	fetus	
C.	ovum	
D.	zygote	

____	45.	The following image shows one stage of a pregnancy.

Which stage of pregnancy is it?

A.	first trimester	
B.	navel formation	
C.	third trimester	
D.	uterine implantation	

____	46.	The developing fetus is shown in the following image. 

Which trimester of pregnancy does this development represent?

A.	first trimester; weeks 1–8	
B.	first trimester; weeks 9–12	
C.	second trimester; weeks 13–27	
D.	third trimester; weeks 28–40	

____	47.	The body’s skeletal and muscular systems work together to produce movement. Which of the following is another important function of the skeletal system?
 
A.	It fights off infections.	
B.	It protects the inner organs.	
C.	It rids the body of waste products.	
D.	It produces testosterone and estrogen.	

____	48.	As children grow older, their bones grow too. The growth of the long bones happens in a plate near the end of each bone. What happens to the cells of cartilage in a growth plate?

A.	Cartilage cells are replaced by bone cells.	
B.	Cartilage cells lengthen to help stretch out the bone.	
C.	Cartilage cells expand and become spongy bone cells.	
D.	Cartilage cells move into spongy bone as bone marrow.	

____	49.	Bones are the major part of the body’s skeletal system. What is one of the main functions of bones?

A.	release growth hormones	
B.	provide structure and support	
C.	carry oxygen to the body’s cells	
D.	serve as the main source of calcium 	

____	50.	Children have a different number of bones than adults do. Why is this the case?

A.	As children develop, they grow new bones, and adults have more bones as a result.	
B.	As children develop, some of their bones fuse together, and adults have fewer bones as a result.	
C.	As children develop, some of their bones separate into smaller bones, and adults have more bones as a result.	
D.	As children develop, their bones become damaged and they experience bone loss, and adults have fewer bones as a result.	

____	51.	This image shows the structure of an arm. The arm can bend or straighten because of a joint that forms the elbow.

Which type of joint is the elbow?

A.	fixed	
B.	hinge	
C.	gliding	
D.	ball-and-socket	

____	52.	This image shows the structure of a joint. Joints can have several different parts, including cartilage and ligaments.

What function does cartilage perform in a joint?

A.	It cushions the bones.	
B.	It contracts and relaxes.	
C.	It connects bones together.	
D.	It connects bones to muscles.	

____	53.	A joint that does not allow movement is called a fixed joint. Which of the following is an example of a fixed joint?

A.	ankle	
B.	knee	
C.	neck	
D.	skull	

____	54.	Which part of the skeletal system is a place where two or more bones connect?

A.	calcium	
B.	joint	
C.	marrow	
D.	tendon	

____	55.	Why is the muscle action in the heart and other organs known as involuntary muscle action?

A.	Diet controls the action of the heart and other organ muscles.	
B.	The tendons control the action of the heart and other organ muscles.	
C.	The person chooses to control the action of the heart and other organ muscles.	
D.	The person cannot consciously control the action of the heart and other organ muscles.	

____	56.	Skeletal muscles are attached to bones to allow movement. Skeletal muscles have a striped appearance. This image shows a magnified view of skeletal muscle.

Which of the following is true of skeletal muscles?

A.	Skeletal muscles are an example of cardiac muscle.	
B.	Skeletal muscles are an example of smooth muscle.	
C.	Skeletal muscles are an example of voluntary muscle.	
D.	Skeletal muscles are an example of involuntary muscle.	

____	57.	Jeff fell while playing basketball and dislocated his shoulder. Jeff’s doctor told him that he had injured an important part of his skeletal system. But luckily, it will heal quickly. What part of the skeletal system is injured when a shoulder is dislocated?

A.	joint	
B.	spongy bone	
C.	bone marrow	
D.	compact bone	

____	58.	Tetanus is a muscular system disease caused by bacteria. People can become infected if they get a puncture wound, allowing bacteria to get deep under the skin. The bacteria release toxins that interfere with movement. Which of the following is most likely a symptom of tetanus?

A.	inflamed tendons	
B.	stiff and swollen joints	
C.	overstretched or torn ligaments	
D.	uncontrollable muscle contractions	

____	59.	Pairs of muscles often work together to produce movement. The following image shows arm muscles working together.

When the biceps contracts and gets shorter, what does the triceps do?

A.	It relaxes and gets longer.	
B.	It relaxes and gets shorter.	
C.	It contracts and gets longer.	
D.	It contracts and gets shorter.	

____	60.	For a person to move his or her arm, the bones of the arm must work together with a pair of muscles. This image shows the action of the biceps and the triceps muscles.

What is true about the biceps and the triceps?

A.	Both the biceps and the triceps are flexor muscles.	
B.	Both the biceps and the triceps are extensor muscles.	
C.	The biceps is a flexor muscle, and the triceps is an extensor muscle.	
D.	The biceps is an extensor muscle, and the triceps is a flexor muscle.