Unit 4 Conclusion Questions 100 points possible

Activity 4.1.1

  1. How do you think bones, muscles and joints work together to move the body?

Bones give structure and muscles contract to allow the joints to move our boies in different ways.

  1. Your friend Andre comes to school and tells you that he has a dislocated shoulder. Based on what you now know about joints, what do you think this means?

The shoulder is a ball and socket, so the ball has popped out of its socket.

  1. How are tendons and ligaments similar and how are they different?

Tendons and ligaments both are connective tissues, but tendons connect bone to muscle while ligaments connect bone to bone.

  1. Explain why the elbow joint of a cow and the elbow joint of a human have similar, but not identical structure. Think about the actions each organism completes with this limb.

Both elbows have a radius and an ulna, but cow elbows are a hinge joint that only allows them to extend and flex while human elbows are more complex and move in more directions.

  1. What type of joint is the hip joint? Describe the type(s) of movements this joint can perform.

The hip joint is a ball and socket joint that allows full range of motion: flexion, extension, abduction, adduction, and rotation.

Activity 4.1.2

  1. Describe how your range of motion compares to the range of motion of those in your group. Why might there be differences?

My range of motion was lower than my other group member, probably because I am not as active as them.

  1. Which type of joint do you think allows for the greatest number of different movements? Explain your reasoning.

Ball and socket allows for the most movement because it allows for a variety of different joint movements.

  1. What factors influence range of motion of a joint?

Age, gender, flexibility, injury, fat tissue, and activity level are all factors.

  1. Explain how a person can improve flexibility at the joints.

A person can improve flexibility by conditioning the joint with stretches.

  1. Your goniometer breaks. Describe another way you might be able to measure range of motion.

You can use a protractor to measure the angles of motions or joints.

  1. Your favorite team is winning the championship game. You drop to one knee, tip your head back, raise one hand over your head, clench your fist and yell, “Yes.” Use the proper terms to describe the movements undertaken by your joints.

When you drop to your knees you are using abduction to bring your leg closer to your body, by tipping your head back you are using ornaduction because your neck is a pivot joint, when you shoot your hand to the air you are using extension, when you clench you fist you are using depression of your fingers.

  1. You overhear two men at the gym talking about their extensor muscles of the forearm. Based on what you know about the motion at joints, how would you describe the movement of these muscles?

These muscles probably allow them to stretch out so they can do other exercises.

Activity 4.2.1

  1. Describe the differences you see in the three types of muscle tissues.

Skeletal muscle is striated and looks like long fibers. Cardiac muscle is striated and has visible nuclei. Smooth muscle is nonstriated and has a wave type structure with visible nuclei.

  1. What does it mean when we say a muscle contracts involuntarily? Describe one body function that is linked to an involuntary muscle contraction.

Involuntary muscle contraction is when muscles contract without a conscious effort, like the heart for example.

  1. Describe how the structural makeup of a muscle contributes to the muscle’s ability to do its job.

A muscles structure consists of connective tissue and muscle fibers, which work like a rope or rubber band to stretch and contract. The connective tissues’ elasticity and distensibility help to ensure that the tension developed by the muscle is smoothly transmitted and that a muscle will return to its original shape after being stretched.

  1. Using your knowledge of tissues, what type of tissue do you think makes up the three layers of membrane you encountered in your muscle?

I think it is made of smooth muscles because its function is to cover organs and help it retain its shape.

  1. Explain how you know which attachment of a muscle is the origin and which attachment is the insertion.

The insertion of the muscle is the end of the muscle attaching to the freely moving bone of its joint. The origin of the muscle is the end of the muscle attaching to the relatively fixed bone of its joint.

  1. Your mom comes back from the doctor and says she has pulled her tibialis anterior. She knows you are taking Human Body Systems and asks you to tell her about her injury. Based on the classroom discussion, what can you deduce about this muscle?

She has injured the muscle on the backside of her tibia.

  1. When you are cold, your muscles begin to contract involuntarily and cause you to shiver. Why do you think this occurs? How does the contraction of muscles help the body maintain homeostasis?

Shivering causes you to involuntary contract and relaxes your muscles which will increase heat production.

Activity 4.2.2

  1. Look at your Maniken®. Explain to your client why you need multiple exercises to effectively build and tone the muscles of the chest.

You have different muscles in your chest with different insertions and origin so you have to use different exercises to condition all muscles.

  1. Think about the action of the muscles you have built. Describe at least two exercises that will strengthen the muscles of the chest. Make sure to note the specific muscles that are targeted in each exercise. Add information about these exercises to your lab notebook.

Doing push ups would strengthen the pectoralis major. Pulling your arms inward while holding weights and meeting them in the middle would work all the muscles in the chest. Doing “Around the Worlds” will also strengthen muscles in the chest.

  1. Explain how the structure and function of one of the muscles of the chest relates to some of muscle rules you learned in Activity 4.2.1.
  1. Explain how the muscles pectoralis major and serratus anterior show two different ways in which muscles are named.

The serratus anterior is named for its relation to the bone and its origin and muscle fibers. The pectoralis major is named for its size and location in the body.

  1. Are the muscles of pectoralis major adductors or abductors? Explain.

They are major abductors because they can push the shoulder away and bring it closer to the body.

Activity 4.2.4

  1. When you see the glycerinated muscle fibers shorten, what do you think is actually happening in the muscle cells? Think about what you just saw under the microscope.

The muscles are contracting.

  1. Did your muscle samples eventually relax and return to the length they were before contraction? Thinking back to the muscles rules and how your know muscles work, why does this make sense?

They did relax and return relatively to the length they were before. This makes sense because the energy they use to contract eventually gets expelled.

  1. Which solution produced the greatest percent contraction of the muscles? What does this tell you about the requirements for contraction?

The solution with both sodium and glycerol produced the most contraction. Muscles need both sodium and glycerol to contract fully.

  1. Think about the way in which organ systems work together to kick your leg or swing your arm. Besides the skeletal and the muscular system, what other systems do you think are involved in moving the human machine?

The nervous system because in order for muscles to move, there needs to be a signal to the brain.

Activity 4.2.5

  1. How do multiple human body systems work together to cause muscle contraction and movement of the body?

Muscle contractions resulting in movement are a symphony of coordination between nerve impulses, brain cells and muscles. It is truly shown how intricate the process is when muscles are retrained to work prothetic devices.

  1. Your friend tried to convince you that the only reason to drink milk and to make sure you get enough calcium is so you can build strong bones. Can you offer him/her another reason?

Calcium regulates muscle contraction, including the heartbeat. It also plays a key role in normal blood clotting.

  1. Explain how it is that actin and myosin in the sarcomere never actually shorten and yet the muscle as a whole does.

Actin and myosin join together making it seem as though the fibers have shortened.

  1. How do ions and electrical charges play a role in communication with the muscle?

Signals from the CNS are sent through efferent pathways for actin and myosin to bond and then a message from the muscles is sent back through afferent pathways.

  1. Summarize the science behind rigor mortis. Why is this state a temporary condition?

ATP is still needed for actin and myosin but since the CNS isn’t working, muscles stay contracted. Eventually lysosome will get free and cause muscles to relax.

  1. Using what you know about rigor mortis and about energy, what do you think happens inside your muscle when you get a muscle cramp? Why is this not a permanent condition?

Actin and myosin come together for your muscle to contract, but for some reason ATP could not reach it. But the actin and myosin will eventually release because the body keeps making ATP.

Activity 4.2.6

  1. Given the placement of the ulnar nerve, what type of forearm muscles do you think this nerve stimulates? Explain. HINT: What type of muscles is found on the ventral side of the body?

The pectoralis muscle is located on the ventral side of the body near the ulnar nerve meaning that it is stimulated by it.

  1. Explain how the placement of the ulnar nerve is linked to the pain and discomfort you feel when you bang your “funny bone.”

The ulnar nerve lies in a small space between the medial epicondyle of the humerus and the olecranon of the ulna. There is only skin over this space with no bones or muscles to protect it causing blows to your humerus to be quite painful compared to other less sensitive areas of the body.

  1. Given the placement of the radial nerve, what type of muscles do you think this nerve stimulates? Explain. HINT: What type of muscles is found on the dorsal side of the body?

A muscle called the infraspinatus is located on the dorsal side of your body. It is most often stimulated by the radial nerve because it is located so near to it.

  1. What do you think would happen to a person’s ability to use his/her arm if the radial nerve were damaged?

Severe damage to the radial nerve could force big changes in a person’s life as it is responsible for doing so many tasks. This nerve controls movement in the triceps and sensation in a portion of the hand while also allowing the wrist and fingers to move. When damage to the radial nerve occurs, all of these functions are put in jeopardy.

  1. Describe at least three different jobs that put the worker at risk for carpal tunnel syndrome. How can these individuals lower their risk of injury?

People with jobs such as computer programmers who spend an excessive amount of time typing on their computers, busy handymen with lots of time to hammer away at things, or even teachers with many papers to grade could be at risk for carpal tunnel syndrome. All of these people should take regular breaks to ensure that they are not in danger of this syndrome.

  1. What happens at the junction between a nerve and a muscle to initiate muscle contraction?

Action potentials must be released for muscle contraction to even begin. Motor neurons coding for the movement are sent to that specific muscle.

Activity 4.3.1

  1. How does the structure of smooth and cardiac muscle differ from the structure of skeletal muscle?

Skeletal muscles are striated along with cardiac muscles, but unlike smooth muscles. These types of muscles are also branched, making them similar to smooth muscles but different from cardiac muscles that are unbranched. The only sure difference is that skeletal muscles are multinucleated while both smooth and cardiac are mononucleate muscles. All three of the muscle types have unique locations.

  1. Explain how each of the three types of muscle assist with moving blood around the body.

Cardiac muscles can probably be considered the most important when it comes to moving blood around the body as they are responsible for pumping blood. While it is not all they are responsible for, smooth muscles in the body regulated the flow of blood and blood pressure by controlling the contraction and relaxation of the muscles in the arteries. Skeletal muscles are mainly for maintaining posture and things such as that. Certain body positions allow blood to flow through the body with less difficulty therefore assisting with moving it.

  1. What role do valves play in the heart?

Valves in the heart are vital as they not only regulate blood flow through the heart but also keep blood from flowing in the wrong direction.

  1. Which structure in the heart functions as the natural pacemaker? What does this term mean?

The sinoatrial node is generally referred to as the body’s natural pacemaker, because it is what always initiates cardiac contraction by sending electrical impulses to the rest of the heart.

  1. How does the movement of the electrical impulse relate to the contraction of the chambers of the heart?

Electrical impulses in the heart always begin in the right atrium as that is where the sinoatrial node is located. The start of the impulse controls which chamber will contract next as the impulse travels through the whole of the heart. At one point, the electrical impulse is even delayed to allow the atrioventricular node to allow it to perform a specific task.

  1. What is the difference between pulmonary circulation and systemic circulation?

Pulmonary circulation affects only the right side of the heart, pumping blood to the lungs to take oxygen into the hemoglobin while it also gives off carbon dioxide. This is then returned to the left side of the heart which then pumps blood out to the entire body. The blood that is being pumped to the entire body will eventually return to the right side of the heart to allow the cycle to begin again.

  1. Thinking about function, explain why the left ventricle is much more muscular than the right ventricle.

While the right ventricle only has to pump blood into the lungs to be oxygenated, the left ventricle then has to send the blood through the entire body.

  1. Describe the role of smooth muscle in two human body systems other than the cardiovascular system.

Smooth muscle lines the wall of the stomach and helps the organ to churn up food that has not already been broken down mechanically, making it necessary for the digestive system to function. In the urinary system, smooth muscle is located in the ureters and is responsible for expelling urine.

  1. How does electrical communication in the heart compare to electrical communication in skeletal muscles?

Skeletal muscles require outside forces for electrical communication to occur as action potential must occur before any movement takes place. Electrical communication in the heart starts and ends there without any help from other body systems.

Activity 4.3.2

  1. What do you notice about the width of an artery wall versus the width of a vein wall? Why does this make sense given the function of the vessels?

Arteries have much wider walls as they contain more layers of muscle than veins. This is because arteries must be able to transport high-pressure blood throughout the body unlike veins.

  1. Capillaries function in gas exchange. Describe at least two ways capillary structure is related to this function.

Capillaries must be able to diffuse oxygen and carbon dioxide with ease. Their walls are very thin while also having a large surface area to make this possible.

  1. How do capillaries interact with the respiratory system? Make sure to mention specific structures of the respiratory system. Refer back to your graphic organizer if you need help remembering key anatomy.

The interaction above is fairly simple. Oxygen from the capillaries must be able to move from the alveoli to the blood so that it can then be transported through the body.