Download Unit Four Essential Questions

Marie McClary
Unit 4 Essential Questions
Lesson 4.1 Joints and Motion
1. What role do joints play in the human body?

Joints are the places where the two bones come together and allow movement and
flexibility. Joints also provide support to the human skeleton.
2. How are joints classified by both structure and function?

Joints are classified by if they are fibrous, cartilaginous, or synovial in structure and they
are classified in function by how much they are allowed to move.
3. What are the different types of synovial joints?

The different kinds of synovial joints are the pivot joint, ball-and-socket joint, saddle
joint, condyloid (Ellipsoidal) joint, hinge joint, plane (planar or gliding) joint.
4. What role do cartilage, tendons, and ligaments play at a joint?

Cartilage cushions and protects bones where they meet and rub against each other.
Tendons connect muscles to bones and ligaments fasten bones with other bones.
5. What terms describe the path of movement at a joint?

Abduction, adduction, circumduction, rotation, extension, flexion, flexion, extension,
planter flexion, dorsiflexion all describe the path movement at a joint.
6. What is range of motion?

Range of motion is the range that a joint can be moved and can be measured usiong a
goniometer to determine angles.
7. How do you measure the range of motion of a particular joint movement?

To measure the degree of rage of motion for a joint, you would use a goniometer and an
inclinometer. An inclinometer uses a stationary arm, protractor, fulcrum, and
movement arm to measure angle from axis of joint. Each joint has a normal range of
motion and the two results that are recorded will vary because of resistance.
8. How do bones, muscles and joints work together to enable movement and
locomotion for the human body?

Our bones provide support and give us our shape. The muscles allow us to move and the
joints attach bones to each other. The joints also provide flexibility and they move the
muscles to move the bones.
Lesson 4.2 Muscles Essential Questions
1. How do muscles assist with movement of the body and of substances
around the body?

Muscles allow all of the movement in our bodies and stabilize body position. They also
help to regulate our body’s heat. Muscles help blood move through our bodies and
helps more our bodies voluntarily and involuntarily movement such as the movement of
food down the esophagus and into the stomach.
2. How do the structure and function of the three types of muscle tissue
compare?

The skeletal muscles are striated muscle fibers that are voluntary and contract quickly
and powerfully. They hold the skeleton together and are attached to bone and a
tendon. The smooth muscles are not striated and are involuntary. They take longer than
the skeletal muscles to contract and don’t get as tired as quickly. They make up the
walls of the stomach, blood vessels, and intestines. Cardiac muscles are striated muscle
fibers that form the wall of the heart and are involuntarily. They don’t get tired.
3. How are muscle fibers and membranes organized to form a whole skeletal
muscle?

The epimysium is the outer layer of connective tissue. The perimysium is made of
connective tissue and forms casings for bundles of muscle fibers. The endomysium is
connective tissue surrounding each individual muscle fiber.
4. What do skeletal muscle structure and attachment to bones tell you about
function?

Muscles have an insertion where they attach to the movable bone and an origin and
then they attach to the stationary bone.
5. How are muscles named?

They are named by their location, shape, points of attachment, size, number of muscle
fibers, direction of the muscle fibers, and the association with the characters.
6. What are the requirements for muscle contraction?

Skeletal muscle is voluntary so it requires a stimulus from a nerve impulse. Calcium and
ATP are cofactors that are required for the contraction of muscle cells. ATP supplies the
energy. Calcium is required by two proteins that regulate muscle contraction by blocking
the binding of myosin to actin (Troponin and Tropomyosin). In a resting sarcomere,
tropomyosin blocks the binding of myosin to actin.
7. What role do calcium and ATP play in muscle contraction?

Calcium causes troponin and tropomyosin to shift which exposes myosin binding sites.
The myosin heads connect with the actin binding sites and move the thin filament which
causes the muscle to contract. The ADP and P that caused the myosin heads to turn
back are left behind during the power stroke. The introduction of ATP causes myosin
heads to release the actin. The ATP is broken down into ADP and P which causes myosin
heads to turn back and prepare for another stroke of power.
8. What is a sarcomere?

The contractile unit of a myofibril; sacromeres are repeating structural units or striated
muscle fibrils, delimited by the Z bands along the length or the myofibril.
9. How does a sarcomere contract and lengthen to cause muscle contraction?

Myosin pulls actin and actin pulls the sarcomere’s ends towards the middle.
10.How is the condition rigor mortis related to muscle contraction?

After a person dies actin and myosin shorten muscle fibers. ATP is needed to release the
myosin heads from the actin fibers and allow muscles to relax, but ATP reserves are
quickly depleted, causing muscles to remain contracted. It can take 10 minutes to hours
to occur, with maximum stiffness 12-24 hours after death. Eventually tissue decays and
lysosomal enzymes leak and cause muscles to relax.
11.How do nerves interact with muscles?

In order for muscles to contract, they must receive a message from the CNS to do so.
The messages come through efferent neurons. Afferent neurons send messages back
form muscles to the CNS. If there are problems with nerves, it can lead to issues with
muscles function.
12.How can we assess muscle function?

Heart rate can help assess cardiac muscle function. Strength tests can help assess
function of voluntary muscles.
Lesson 4.3 Blood Flow Essential Questions
1.What types of muscle help move blood around the body?

Smooth muscle.
2.What is the relationship between the heart and the lungs?

Heart pumps the blood to the lungs so the blood can get oxygenated and then pumped
throughout the body.
3.What is the pathway of blood in and out of the heart in pulmonary and
systemic circulation?

The unoxygenated blood enters through the superior vena cava and the inferior vena
cava into the right atrium and then travels through the tricuspid valve in order to enter
the right ventricle. The blood will exit out through pulmonary arteries to the lungs to get
oxygenated. After the blood is oxygenated it then reenters the heart through the
pulmonary veins and into the left atrium. It then enters the left ventricle by using the
bicuspid/ mitral valve then leaves to go throughout the body using the aortic valve and
then through the aorta.
4.How do the structure of arteries, veins and capillaries relate to their function in
the body?

Arteries
Funtion: move blood away from the heart.
Structure: they are more muscular tubes that can withstand large pressure.
Capillaries
Function: join the blood flow from the arterials (small arteries) to the venules (small
veins) where the exchange of nutrients and gases occur at the cellular level.
Structure: capillaries are only one cell thick, allows for easy transport between tissues
and blood vessels.
Veins
Fucntion: move the blood back toward the heart..
Structure: they are larger in diameter and may contain valves to assist in moving the
blood back to the heart
5.What unique features of veins help move blood back to the heart?

Veins have valves at intervals that help prevent reflux of the blood and instead has the
blood flow in a steady stream.
6.What are varicose veins?

They are abnormal swelling of a superficial vein of the legs.
7.Why don’t we ever hear about varicose arteries?

They don’t have valves and they have wall that are made out of muscles.
8.What are the major arteries and veins in the body and which regions do they
serve?

The major arteries are the aorta, coronary, and the pulmonary arteries and the major
veins are the superior vena cava, inferior vena cava, and the pulmonary veins.
9.What is cardiac output?

The volume of blood ejected from the left side of the heart in one minute.
10.How does cardiac output help assess overall heart health?

It can show if your heart is pumping too much or too little blood, which can tell if you
have a faulty heart.
11.How does an increased or decreased cardiac output impact the body?

If a person’s cardiac output is lower than normal, the tissues can suffer or blood
pressure can become unhealthy. Increased cardiac output from exercise can strengthen
the heart.
12.What is blood pressure?

The hydrostatic force that blood exerts against the wall of a vassel.
13.How can the measurement of blood pressure in the legs be used to assess
circulation?

It can be taken to measure how well blood is circulating to those limbs.
14.What is peripheral artery disease?

It is a vascular disease affecting blood vessels outside of the heart and especially the
vessels that supply blood to the extremities.
15.Why can smoking lead to peripheral artery disease?

It can damage the endothelium, which allows plaque to build up on the artery walls.
Lesson 4.4 Energy and Motion: Exercise Physiology
1.What is the connection between power and movement in the body?

ATP
2.How does the body maintain a supply of ATP during exercise?

During exercise you use cellular respiration and glycolysis. In glycolysis only 2 ATP are
created but in cellular respiration 36 ATP are created.
3.What body systems are involved with powering an athlete through a running
race?

Muscular system, skeletal system, respiratory system, cardiac system, and the nervous
system.
4.What is muscle fatigue?

It is the decline in ability of a muscle to generate force.
5.How are we able to overcome muscle fatigue?

By having a good nutrition, being hydrated, and having endurance.
6.What are performance-enhancing drugs?

Performance-enhancing drugs (also known as PEDs) are substances used to
improve performance in situations like sports.
7.How do specific performance-enhancing drugs affect the human body?

A person can have liver abnormalities or tumors, increase in LDL cholesterol, decrease in
HDL cholesterol, high blood pressure, heart and circulatory problems, growth problems,
and aggressive behavior.
8.Why should certain performance-enhancing drugs be banned from athletic
competition?

It gives players taking the drug an unfair advantage while the other players are playing
using their talents. The drug also makes users violent which could easily get an
unsuspecting player hurt.
9.What are areas to consider when designing a training plan for an athlete?

Age, current or recent injuries, any health problems, what sport facilities they have
access to like a gym, and their dislikes and like for training.