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Do you know the cardiovascular and respiratory systems? The cardiovascular system consists of the heart and blood vessels. The heart completes the function of pumping blood vessels through the body, and blood is delivered to a different part of the body. The respiratory system's anatomy includes the nose, pharynx, larynx, trachea, bronchi, and lungs. If If the notion of an exam makes your heart skip a beat, this quiz can help.
Questions and Answers
1.
How much blood is in the human body?
A.
7 Litres
B.
5-6 Litres
C.
4 Litres
D.
5-6 Gallons
E.
4 Gallons
Correct Answer
B. 5-6 Litres
Explanation The correct answer is 5-6 Litres. This is the average amount of blood in the human body. The volume of blood can vary depending on factors such as age, sex, and body size, but on average, an adult human has approximately 5-6 liters of blood circulating in their body. Blood plays a vital role in transporting oxygen, nutrients, hormones, and waste products throughout the body, as well as regulating body temperature and maintaining overall health and homeostasis.
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2.
3 primary formed elements of the blood are all of these except:
A.
Marrow
B.
Red blood cells
C.
White blood cells
D.
Platelets
Correct Answer
A. Marrow
Explanation The question asks for the exception among the three primary formed elements of blood. Marrow is not considered one of the formed elements of blood. Marrow is a soft, gelatinous tissue found inside the bones, and it is responsible for producing red blood cells, white blood cells, and platelets. Therefore, marrow is not an exception among the three primary formed elements of blood.
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3.
Red blood cells:
A.
Least amount in blood
B.
Contain organelles
C.
Made up of hemoglobin, carry oxygen
D.
Remove debris
E.
Do not exist
Correct Answer
C. Made up of hemoglobin, carry oxygen
Explanation Red blood cells are made up of hemoglobin, a protein that allows them to carry oxygen throughout the body. This is their main function, as they pick up oxygen from the lungs and deliver it to all the tissues in the body. Red blood cells do not contain organelles and are specifically designed to be able to carry oxygen efficiently. They also play a role in removing debris and waste products from the body. The statement "do not exist" is incorrect and does not apply to red blood cells.
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4.
White blood cells:
A.
Carry oxygen
B.
Have no organelles
C.
Made up of hemoglobin
D.
Contain all the sytoplasmic organelles, remove debris, fight infections
E.
Do not exist
Correct Answer
D. Contain all the sytoplasmic organelles, remove debris, fight infections
Explanation White blood cells contain all the cytoplasmic organelles, remove debris, and fight infections. These cells are an essential part of the immune system and play a crucial role in defending the body against pathogens. They have various organelles, such as mitochondria, endoplasmic reticulum, and Golgi apparatus, which are responsible for carrying out different cellular functions. White blood cells also have the ability to engulf and destroy foreign particles and dead cells, thereby removing debris from the body. Additionally, they produce antibodies and release chemicals to combat infections and protect the body from harmful microorganisms.
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5.
Platelets
A.
Contain organelles
B.
Graules (sacs) that help clot blood
C.
Remove debris
D.
Carry oxygen
E.
Do not exist
Correct Answer
B. Graules (sacs) that help clot blood
Explanation Platelets are small fragments of cells that circulate in the bloodstream. They contain organelles called granules or sacs, which play a crucial role in blood clotting. When there is an injury, these granules release various substances that initiate the clotting process. They help in the formation of a clot, which prevents excessive bleeding. Therefore, the presence of granules in platelets is essential for their function in clotting blood.
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6.
Blood transports all except:
A.
Nutrients: digested, then absorbed
B.
Gases: oxygen, carbon dioxide
C.
Wastes: urea, ammonia, CO2
D.
Heat: produced by muscles
E.
Cargo: luggage, clothing
F.
Defenses: clotting, immune responses
G.
Hormones: protein or steroid based molecules
H.
Drugs/Toxins: medications, drugs
Correct Answer
E. Cargo: luggage, clothing
Explanation Blood transports various substances such as nutrients, gases, wastes, heat, defenses, hormones, and drugs/toxins. Nutrients are digested and absorbed, gases like oxygen and carbon dioxide are carried, wastes like urea, ammonia, and CO2 are transported, heat produced by muscles is circulated, defenses such as clotting and immune responses are carried, hormones (protein or steroid based molecules) are transported, and drugs/toxins like medications and drugs are also transported. However, blood does not transport cargo like luggage and clothing.
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7.
The heart lies in a chamber called:
A.
Heart valve
B.
Mediastinum
C.
Heart chamber
D.
Mediacenter
E.
Heartstinum
Correct Answer
B. Mediastinum
Explanation The heart lies in a chamber called the mediastinum. The mediastinum is the central compartment of the thoracic cavity, located between the lungs. It contains various structures including the heart, great vessels, esophagus, and trachea. The heart is specifically situated within the mediastinum, where it is protected and surrounded by other vital structures.
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8.
The heart is _______ to the esophagus, and _______ to the diaphragm.
A.
Anterior, superior
B.
Superior, anterior
C.
Anterior, anterior
D.
Superior, superior
E.
Nowhere
Correct Answer
A. Anterior, superior
Explanation The heart is positioned in front of the esophagus, making it anterior to the esophagus. Additionally, the heart is located above or superior to the diaphragm. Therefore, the correct answer is "anterior, superior."
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9.
The layers of the heart from superficial to deep are:
Explanation The correct answer is fibrous pericardium, serous membrane (parietal pericardium, visceral pericardium), myocardium, endocardium. This is the correct order of the layers of the heart from superficial to deep. The fibrous pericardium is the outermost layer, followed by the serous membrane which consists of the parietal pericardium and the visceral pericardium. The myocardium is the middle layer and is responsible for the contraction of the heart. The endocardium is the innermost layer and lines the chambers of the heart.
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10.
The 4 chambers of the heart are all except
A.
Left atria
B.
Septum
C.
Right atria
D.
Right ventricle
E.
Left ventricle
Correct Answer
B. Septum
Explanation The septum is not one of the chambers of the heart. The heart is divided into four chambers: the left atrium, right atrium, left ventricle, and right ventricle. The septum, on the other hand, is a wall of tissue that separates the left and right sides of the heart. It helps to prevent the mixing of oxygen-rich and oxygen-poor blood.
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11.
Atria heart chambers are
A.
On the left
B.
On the bottom
C.
On the top
D.
On the right
E.
Nowhere
Correct Answer
C. On the top
Explanation The atria heart chambers are located on the top. This is because the heart is positioned in the chest cavity with the atria sitting on top of the ventricles. The atria receive blood returning to the heart from the body and lungs, and then pump it into the ventricles. The ventricles, on the other hand, are located on the bottom of the heart.
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12.
Ventricle heart chambers are
A.
On the top
B.
On the bottom
C.
On the left
D.
On the right
Correct Answer
B. On the bottom
Explanation The ventricle heart chambers are located on the bottom. The ventricles are the lower chambers of the heart that pump blood out to the body and lungs. They are positioned beneath the atria, which are the upper chambers of the heart. The ventricles are responsible for pumping oxygenated blood to the body and deoxygenated blood to the lungs for oxygenation. Being positioned at the bottom allows the ventricles to efficiently pump blood throughout the circulatory system.
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13.
The true pumps of the hearts are
A.
The atria
B.
The ventricles
C.
The septum
D.
All of it
Correct Answer
B. The ventricles
Explanation The correct answer is the ventricles. The ventricles are the main pumping chambers of the heart and are responsible for pumping blood to the rest of the body. The atria, on the other hand, receive blood from the veins and pass it on to the ventricles. The septum is a wall that separates the left and right sides of the heart. While all of these components play a role in the functioning of the heart, the ventricles are specifically responsible for the pumping action.
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14.
The valves of teh heart are all except
A.
Papillary (center)
B.
Atrioventricular (Tricuspid (right))
C.
Atrioventricular (bicuspid (left))
D.
Pulmonary (right)
E.
Aortic (left)
Correct Answer
A. Papillary (center)
Explanation The valves of the heart include the atrioventricular valves (tricuspid on the right side and bicuspid on the left side), pulmonary valve (on the right side), and aortic valve (on the left side). However, papillary valves are not a part of the heart's valve structure. Therefore, the correct answer is papillary (center).
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15.
Blood vessels that lead to the myocardium
A.
Left and right testicles
B.
Left and right ventricles
C.
Left and right atria
D.
Left and right coronary arteries
Correct Answer
D. Left and right coronary arteries
Explanation The left and right coronary arteries are the blood vessels that supply oxygenated blood to the myocardium, which is the muscular tissue of the heart. These arteries branch off from the aorta and wrap around the heart, providing essential nutrients and oxygen to the heart muscle. Without the left and right coronary arteries, the myocardium would not receive adequate blood supply, leading to ischemia and potentially causing a heart attack or other cardiovascular complications.
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16.
Cardiac muscle is
A.
Striated
B.
Squamous
C.
Columnar
D.
Pumped
Correct Answer
A. Striated
Explanation Cardiac muscle is classified as striated because it has a striped or striated appearance under a microscope. This is due to the arrangement of contractile proteins called myofilaments within the muscle cells. The presence of these myofilaments gives cardiac muscle its characteristic striated appearance, similar to skeletal muscle.
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17.
The heart is systole when
A.
When the ventricles (main pumping chambers) contract
B.
When the ventricles (main pumping chambers) relax and fill up
C.
When the atria contract
D.
When the atria relax and fill up
Correct Answer
A. When the ventricles (main pumping chambers) contract
Explanation When the ventricles (main pumping chambers) contract, the heart goes through systole. During systole, the ventricles forcefully pump blood out of the heart and into the arteries. This is an important phase of the cardiac cycle as it allows for the circulation of oxygenated blood to the rest of the body.
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18.
Diastole is when
A.
The ventricles relax and fill up with blood
B.
The ventricles contract
C.
The atria contract
D.
The atria relax and fill up with blood
E.
A heart diet
Correct Answer
A. The ventricles relax and fill up with blood
Explanation During diastole, the ventricles of the heart relax, allowing them to expand and fill up with blood. This phase occurs after the ventricles have pumped blood out to the rest of the body during systole. The relaxation of the ventricles allows them to refill with oxygenated blood from the atria, preparing them for the next contraction. This process ensures a continuous flow of blood throughout the body and is essential for proper heart function.
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19.
The vena cava (largest veins) return deoxygenated blood to the
A.
Right ventricle
B.
Left atrium
C.
Right atrium
D.
Left ventricle
Correct Answer
C. Right atrium
Explanation The vena cava is a large vein that carries deoxygenated blood from the body back to the heart. It has two main branches, the superior vena cava and the inferior vena cava. The superior vena cava brings deoxygenated blood from the upper body, while the inferior vena cava brings deoxygenated blood from the lower body. Both of these veins empty into the right atrium of the heart. Therefore, the correct answer is right atrium.
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20.
When blood enters the right atrium it falls into the ______ because the tricuspid valve is open
A.
Septum
B.
Left atria
C.
Right atria
D.
Left ventricle
E.
Right ventricle
Correct Answer
E. Right ventricle
Explanation When blood enters the right atrium, it falls into the right ventricle because the tricuspid valve is open. The tricuspid valve is located between the right atrium and right ventricle, and when it is open, it allows blood to flow from the atrium into the ventricle. This is part of the normal flow of blood through the heart, as the right ventricle pumps the blood to the lungs to be oxygenated.
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21.
The blood exists the pulmonary arteries and goes to the lungs for oxygen and then
A.
Goes in the left vena cava, left atria, left ventricle
B.
Goes in the right vena cava, right atria, right ventricle
C.
Goes to the brain
D.
Goes to the nose
Correct Answer
B. Goes in the right vena cava, right atria, right ventricle
Explanation In the circulatory system, deoxygenated blood is pumped from the right ventricle of the heart into the pulmonary arteries, which carry it to the lungs for oxygenation. After being oxygenated in the lungs, the blood returns to the heart through the pulmonary veins and enters the left atria and then the left ventricle before being pumped out to the rest of the body.
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22.
The lub sound of the heart is
A.
The tricuspid valve closing
B.
The tricuspid valve opening
C.
Semilunar valve closing
D.
Semilunar valve opening
Correct Answer
A. The tricuspid valve closing
Explanation The lub sound of the heart is caused by the tricuspid valve closing. This valve is located between the right atrium and right ventricle of the heart. When the ventricles contract, the tricuspid valve closes to prevent blood from flowing back into the atrium. This closure creates a sound that can be heard as the lub sound during a heartbeat.
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23.
The dub sound of the heart is
A.
Semilunar valve closing
B.
Semilunar valve opening
C.
Tricuspid valve closing
D.
Tricuspid valve opening
E.
None
Correct Answer
A. Semilunar valve closing
Explanation The correct answer is semilunar valve closing. The dub sound of the heart is produced when the semilunar valves, which are located between the ventricles and the major arteries leaving the heart, close. This closure prevents the backflow of blood into the ventricles and ensures that blood flows in one direction. The closing of the semilunar valves creates a distinct sound that can be heard during a cardiac examination.
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24.
Common ways to regulate the heart include all except
A.
Voluntary control
B.
Autonomic nervous system (fight or flight)
C.
Endocrine system (released during stress)
D.
Physical factors (body temperature)
Correct Answer
A. Voluntary control
Explanation The heart is primarily regulated by the autonomic nervous system and the endocrine system. The autonomic nervous system controls the heart rate and rhythm, while the endocrine system releases hormones like adrenaline during stress, which can affect heart function. Physical factors such as body temperature can also influence heart rate. However, voluntary control, or conscious control over the heart rate, is not a common way to regulate the heart.
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25.
Blood vessel lining from superficial to deep
A.
Tunica media, tunica externa, tunia intima
B.
Tunica intima, tunica media, tunica extrena
C.
Tunica externa, tunica media, tunica intima
Correct Answer
C. Tunica externa, tunica media, tunica intima
Explanation The correct answer is tunica externa, tunica media, tunica intima. This is the correct order of the layers of the blood vessel lining from superficial to deep. The tunica externa is the outermost layer, followed by the tunica media in the middle, and finally the tunica intima on the innermost layer.
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26.
Path of blood through the body
A.
Oxygenated blood exits the heart, moves through major arteries, subdivides into smaller arteries, blood enters the capillary network and oxygen is delivered to body tissues and becomes deoxygenated, blood enters venules of a venous system, blood drains to major veins and returns to the heart
B.
No
Correct Answer
A. Oxygenated blood exits the heart, moves through major arteries, subdivides into smaller arteries, blood enters the capillary network and oxygen is delivered to body tissues and becomes deoxygenated, blood enters venules of a venous system, blood drains to major veins and returns to the heart
Explanation This answer correctly describes the path of blood through the body. It starts with oxygenated blood leaving the heart and moving through major arteries. It then subdivides into smaller arteries before entering the capillary network where oxygen is delivered to body tissues and the blood becomes deoxygenated. The deoxygenated blood then enters venules of a venous system and eventually drains into major veins, which return the blood back to the heart.
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27.
Arteries are all except
A.
Blood travels away from the heart
B.
No valves
C.
More smooth muscle
D.
Less smooth muscle
Correct Answer
D. Less smooth muscle
Explanation Arteries are blood vessels that carry oxygenated blood away from the heart to the rest of the body. They have thick, elastic walls that contain smooth muscle. This smooth muscle allows arteries to constrict and dilate, regulating blood flow and maintaining blood pressure. Therefore, the statement "less smooth muscle" is incorrect because arteries actually have more smooth muscle compared to other blood vessels like veins and capillaries.
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28.
Veins are all except
A.
Blood travels towards the heart
B.
Larger veins have valves
C.
No valves
D.
Less smooth muscle
Correct Answer
C. No valves
Explanation Veins are blood vessels that carry deoxygenated blood back to the heart. The statement "no valves" is the correct answer because veins typically have valves that prevent the backflow of blood. These valves ensure that blood moves in one direction, towards the heart. Valves are particularly important in larger veins, such as in the legs, where they help counteract the effects of gravity and assist in the upward flow of blood. The absence of valves in veins would disrupt the proper circulation of blood and hinder its return to the heart.
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29.
Air treatment involves all of the following except
A.
Purified
B.
Humidified
C.
Created
D.
Warmed
Correct Answer
C. Created
Explanation Air treatment involves processes such as purifying, humidifying, and warming the air to improve its quality and comfort. However, "creating" air is not a part of air treatment as air already exists naturally. Therefore, the correct answer is "created".
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30.
The structures of the respiratory track all except
A.
Mouth
B.
Nose
C.
Pharynx
D.
Larnyx
Correct Answer
A. Mouth
Explanation The mouth is not considered a part of the respiratory tract. The respiratory tract starts with the nose, which filters and warms the air, and then continues to the pharynx, where the air is further filtered and moistened. From there, the air moves to the larynx, where sound is produced, and then down into the trachea and lungs. The mouth, although involved in the process of breathing, is primarily responsible for other functions such as eating and speaking.
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31.
What purifies the air
A.
Mucus and cilia
B.
Cilia and nose hairs
C.
Mucus and boogers
D.
Lysol
E.
Febreeze
Correct Answer
A. Mucus and cilia
Explanation Mucus and cilia work together to purify the air. Mucus is a sticky substance produced by the respiratory system that traps dust, bacteria, and other particles in the air. Cilia are tiny hair-like structures that line the respiratory tract and move in coordinated waves. These cilia help to move the trapped particles, along with the mucus, out of the respiratory system, preventing them from entering the lungs. This process helps to filter and purify the air we breathe.
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32.
These are true of the pharynx except for
A.
Voicebox
B.
Throat
C.
Muscular tube
D.
Made up for 3 segments; oro, larngo, naso
Correct Answer
A. Voicebox
Explanation The correct answer is "voicebox" because the voicebox, also known as the larynx, is actually a part of the pharynx. The pharynx is a muscular tube that is made up of three segments: the oro (mouth), laryngo (voicebox), and naso (nose) segments. Therefore, the voicebox is not excluded from the characteristics of the pharynx, making it the exception in this list.
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33.
These are true of the larynx except for
A.
Voicebox
B.
Surrounded by hyaline cartilage
C.
Protected by the epiglottis
D.
Throat
Correct Answer
D. Throat
Explanation The given options describe characteristics of the larynx, except for "throat." The larynx is commonly known as the voicebox and is surrounded by hyaline cartilage. It is protected by the epiglottis, which prevents food from entering the airway during swallowing. However, the larynx is not synonymous with the throat. The throat refers to the entire passage that includes the larynx, pharynx, and esophagus. Therefore, the option "throat" does not accurately describe the larynx.
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34.
These are true of the trachea except for
A.
Windpipe
B.
Voicebox
C.
Supported by c shaped cartilaginous rings
D.
Lines with pseudostratified columnar epithlia
Correct Answer
B. Voicebox
Explanation The trachea, also known as the windpipe, is a tube that connects the larynx (voicebox) to the bronchi of the lungs. It is supported by C-shaped cartilaginous rings, which prevent it from collapsing and maintain its shape. The trachea is lined with pseudostratified columnar epithelium, which helps to protect and lubricate the airway. Therefore, the correct answer is "voicebox" because the trachea is not the same as the larynx, which is responsible for producing sound.
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35.
All at true of the bronci and bronchioles except for
A.
3 segments
B.
Branch from trachea towards different lungs
C.
5 branches lead to 5 lobes of the lungs
D.
3 air sacs of the right and 2 on the left
Correct Answer
A. 3 segments
Explanation The correct answer is 3 segments. This is because the bronchi and bronchioles do not have 3 segments. The bronchi and bronchioles are the airways that branch from the trachea towards the different lobes of the lungs. They further divide into smaller branches called bronchioles. The 5 branches leading to the 5 lobes of the lungs and the presence of 3 air sacs on the right and 2 on the left are all true statements about the bronchi and bronchioles.
Explanation The correct answer is the sequence of structures that air passes through in the respiratory system: trachea, primary bronchus, secondary bronchus, tertiary bronchus, bronchiole, and alveoli. This is the correct order in which air travels from the upper respiratory tract down into the lungs. The trachea is the main airway that connects the throat to the bronchi, which then branch out into smaller airways called bronchioles. The bronchioles lead to tiny air sacs called alveoli, where gas exchange occurs.
Explanation The correct answer is 1. pulmonary ventilation, 2. external respiration, 3. transport, 4. internal respiration. These are the four main stages of respiration. Pulmonary ventilation refers to the movement of air in and out of the lungs. External respiration is the exchange of oxygen and carbon dioxide between the lungs and the blood. Transport refers to the transportation of oxygen and carbon dioxide through the bloodstream. Internal respiration is the exchange of oxygen and carbon dioxide between the blood and the body's tissues.
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38.
L
A.
Elastic ligaments between vertebrae
B.
Widely distributed throughout body
C.
Attached to muscle bone
Correct Answer
C. Attached to muscle bone
Explanation The correct answer is "attached to muscle bone" because the description provided states that the elastic ligaments are attached to muscle bone. This suggests that the ligaments are connected to both muscle tissue and bone tissue, indicating their role in providing support and stability to the musculoskeletal system.
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39.
Elastic cartilage can be found in the...
A.
Costal cartilages of ribs
B.
External ear
C.
Under skin
D.
Intervertebral disks
Correct Answer
B. External ear
Explanation Elastic cartilage is found in the external ear. This type of cartilage contains elastic fibers, which give it flexibility and the ability to return to its original shape after being bent or stretched. The external ear, also known as the pinna, is composed mainly of elastic cartilage. This allows the ear to be flexible and helps in capturing sound waves and directing them into the ear canal.
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40.
Fibrocartilage...
A.
Connects structure subjected to great pressure
B.
Energy storage
C.
Provides support, site of bone growth
D.
Provides rigidity with flexibility
Correct Answer
A. Connects structure subjected to great pressure
Explanation Fibrocartilage is a type of cartilage that is found in structures that are subjected to great pressure, such as the intervertebral discs in the spine and the pubic symphysis in the pelvis. It is characterized by its strong and dense fibers, which allow it to withstand and absorb the forces exerted on these structures. Therefore, fibrocartilage serves the function of connecting and providing support to structures that are under significant pressure.
Correct Answer
C. Merkel's disk, Meissner's corpuscles, pacinian corpuscles
Explanation The correct answer is Merkel's disk, Meissner's corpuscles, pacinian corpuscles. This is because Merkel's disk is located in the top layer of the skin and is responsible for light touch and pressure sensation. Meissner's corpuscles are located in the middle layer of the skin and are responsible for detecting light touch and vibration. Pacinian corpuscles are located in the deeper layers of the skin and are responsible for detecting deep pressure and vibration. Therefore, the correct order from top to bottom is Merkel's disk, Meissner's corpuscles, pacinian corpuscles.
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42.
From outward to inner
A.
Cornea, iris, pupil, lens, vitreous
B.
Lens, pupil, iris, vitreous, cornea
C.
Iris, lens, cornea, pupil
Correct Answer
A. Cornea, iris, pupil, lens, vitreous
Explanation The correct order is cornea, iris, pupil, lens, vitreous. The cornea is the outermost layer of the eye, followed by the iris which controls the size of the pupil. The pupil is the opening in the center of the iris that allows light to enter the eye. The lens is located behind the iris and helps to focus light onto the retina. The vitreous is a gel-like substance that fills the back of the eye, providing it with shape and support.
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43.
Action potential...
A.
None of the below
B.
Neuroglia receive stimuli
C.
Occurs when neurons receive stimuli
D.
Is caused when the charge across the cell membrane is briefly reversed
Correct Answer
D. Is caused when the charge across the cell membrane is briefly reversed
Explanation Action potential is a brief electrical signal that travels along the axon of a neuron. It is initiated when the charge across the cell membrane reaches a certain threshold and becomes briefly reversed. This reversal of charge, known as depolarization, allows the action potential to propagate along the neuron. Therefore, the correct answer is that action potential is caused when the charge across the cell membrane is briefly reversed.
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44.
Depolarization
A.
Charge changes from positive to negative, potassium rushes out
B.
Charge changes from negative to positive, sodium rushes in
C.
Charge changes from negative to positive, potassium rushes in
Correct Answer
B. Charge changes from negative to positive, sodium rushes in
Explanation During depolarization, the charge inside the cell changes from negative to positive. This occurs when sodium ions rush into the cell through sodium channels. This influx of positive ions causes the cell membrane to become less negative, leading to depolarization.
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45.
Repolarization
A.
Charge changes from negative to positive, sodium rushes in
B.
Charge changes from positive to negative, opening voltage gated channels, potassium rushes out
C.
Charge changes from positive to negative, opening ligand gated channels, sodium rushes in
D.
Charge changes from negative to positive, opening ligand gated channels, sodium rushes in
Correct Answer
B. Charge changes from positive to negative, opening voltage gated channels, potassium rushes out
Explanation During repolarization, the charge inside the cell changes from positive to negative. This change in charge causes the voltage-gated channels to open, allowing potassium ions to rush out of the cell. This movement of potassium ions out of the cell helps to restore the cell's resting membrane potential and brings the charge back to a negative value.
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46.
Action potential travels down the T-tubules --> release of ca+ ions from sacroplasma ER --> Ca+ binds to tryponin -->
A.
Charge changes from positive to negative, opening ligand gated channels, sodium rushes in
B.
Pulls trypomyosin off actin
C.
Reveals binding spot for myosin
Correct Answer
B. Pulls trypomyosin off actin
Explanation The correct answer states that the release of Ca+ ions from the sarcoplasmic reticulum causes a change in charge from positive to negative. This change in charge opens ligand-gated channels, allowing sodium to rush into the cell. As a result, trypomyosin is pulled off actin, revealing the binding spot for myosin. This explanation provides a clear and concise understanding of the sequence of events that occur during muscle contraction.
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47.
Myosin binds actin --> ADP and Pi release -->
A.
ATP binds to myosin
B.
Stroke motion
C.
Myosin is release
Correct Answer
B. Stroke motion
Explanation The given answer suggests that the stroke motion occurs after ATP binds to myosin. This indicates that the binding of ATP to myosin is a crucial step in initiating the stroke motion. The release of ADP and Pi from myosin that happens prior to ATP binding is likely responsible for the energy required for the stroke motion to occur. Once the stroke motion is complete, myosin is released, allowing it to bind to actin again and continue the contraction process.
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48.
ATP hydrolizes to...
A.
ADP
B.
ADP and Pi
C.
Pi
Correct Answer
B. ADP and Pi
Explanation ATP (adenosine triphosphate) is a molecule that stores and releases energy in living cells. When ATP is hydrolyzed, it breaks down into ADP (adenosine diphosphate) and inorganic phosphate (Pi). This process releases energy that can be used by the cell for various metabolic reactions. Therefore, the correct answer is ADP and Pi, as both products are formed when ATP is hydrolyzed.
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49.
For myosin to be release
A.
ADP and Pi must be hydrolized
B.
Myosin must bind to trypomyosin
C.
ATP must bind to myosin
D.
None of the above
Correct Answer
C. ATP must bind to myosin
Explanation When ATP binds to myosin, it provides the necessary energy for myosin to release from actin filaments. This allows the muscle contraction cycle to continue. ADP and Pi being hydrolyzed are necessary steps in the contraction cycle but do not directly cause myosin release. Binding of myosin to tropomyosin is also a step in muscle contraction, but it does not specifically lead to myosin release. Therefore, the correct answer is that ATP must bind to myosin for myosin to be released.
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50.
Random question: Did you remember to study cellular respiration?
A.
Yes
B.
No
Correct Answer
A. Yes
Explanation The given correct answer is "Yes" because the question is asking if the person remembered to study cellular respiration. By answering "Yes," it implies that the person did remember to study cellular respiration.
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