HBS 4.2.1 and 4.2.2

Step 1 of rigor mortis

A motor neuron sends an impulse (action potential) to the muscle fibers at the neuromuscular junction. This is the area where the motor neurons axon and the muscle fibers meet

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

.25% ATP in salt solution

Explain how the structure and the function of one of the muscles of the chest relates to the muscle rules you learned in activity 4.2.1

Rule 1: muscles must have at least 2 attachments and must cross at least 1 joint Serratus anterior origin is on the surface of the 1st to 8th ribs at the side and the insertion is along the entire anterior length of the medial border of the scapula where the ball-socket shoulder joint is located

pectoralis minor example

Shoulder girdle stretch

Explain how the central and peripheral nervous system together allow you to pick up a can of soda?

Signal in brain (CNS) goes to the spinal cord, to an extensor muscle in the PNS to grab the can and flexor muscles to pick it up

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

When a muscle contracts the space between the cell s is shortened and they become more closely packed together. Under the microscope we saw the striation getting closer together, becoming more compact

histology of skeletal muscle

a bundle of muscle fibers each with a long multinucleated cell in a parallel formation (multiple nuclei)

moving a part toward the midline

adduction

location of skeletal muscle

attached to bones

movements in all planes, and rotational movement

ball and socket joint movement

ball shaped process of one bone fits into the cup shaped socket of another

ball socket joint structure

types of synovial joints

ball socket, pivot, hinge, saddle, condyloid (ellipsoidal), and planar (plane or gliding)

Tricep brachi medial head

behind

between metacarpals and phalanges

condyloid (ellipsoidal) joint example

an oval shaped structure of one bone fits into a cavity of another bone

condyloid (ellipsoidal) joint structure

back and forth, and circular movements

condyloid (ellipsoidal) movement

lowing a part

depression

orbicularis oculi and transverse abdominis

direction

bending the foot at the ankle toward the shin

dorsiflexion

raising a part

elevation

bending parts at a joint so that the angle between them decreases

flexion

Brachialis (bicep)

front

location of cardiac muscle

heart

function of cardiac muscle

heart contraction

type of cartilage in joints

hyaline cartilage

articulation =

joint

an elastic band of tissue that connects bone to bone and provides stability to the joint

ligaments

Muscle rule #4

muscles that decrease the angle between ventral surfaces of the body are flexors. muscles that increase the angle between ventral surfaces of the body are extensors

axis and atlas (parts of neck)

pivot joint examples

movement is limited around a central axis

pivot joint movement

a clindrical surface of one bone rotates within a ring formed by antoer

pivot joint structure

ankles and wrist

plane (planar or gliding) joint examples

allowing sliding and twisting motion

plane (planar or gliding) joint movement

articulating bones are flat or slightly curved

plane (planar or gliding) joint structure

bending the foot at the ankle toward the sole

plantar flexion

moving a part around an axis

rotation

carpal and metacarpal of the thumb

saddle joint example

allow back and forth, side to side, and some pivotal movements

saddle joint movement

forms between bones whose articulating surfaces that both have concave and convex surfaces

saddle joint structure

trapezium and rhomboid minor

shape

Muscle rule #3

the attachment that moves is known as the insertion (distal) and the attachment that remains stationary is known as the origin (proximal)

histology of cardiac muscle

tightly connected by junctions in a parallel formation ad have a central (single) nucleus

Makes a V at C7 and T1, travels under the clavicle, down the armpit, down the medial side of the humerus, stops before going onto the middle finger, and branche to the ring and little finger

ulnar nerve

pectoralis major clavicular head example

weightlifting

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

Ball and socket because the socket part of the joint doesn't restrict the rotation of the ball part of the joint at all (multiaxial - move in lots of different planes)

What type of joint is the hip joint? What type(s) of movement can this joint carry out?

Ball and socket joint Movements in all planes, and rotational movement

How can an individual improve their range of motion at a particular joint?

Stretching exercises, improve health and exercises

What are the 6 types of joints?

Ball and socket joint , condyloid (ellipsoidal) joint, plane (planar or gliding) joint, hinge joint, and pivot joint, saddle joint

Describe how the structural makeup of a muscle contributes to the muscles ability to do its job.

Branching allows the cells to communicate with cells around them (allowing the cells on the heart to beat in rhythm); Some cells must have more than one nucleus to increase the amount of DNA and increase the synthesis of proteins; Muscles have a lot of mitochondira because it allows a lot of ATP to be used

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 off him/her another reason?

Calcium is also a main component in the contraction of our muscles which helps us move

What can low the rick of injury to the carpal tunnel?

Changing angle of typing, taking breaks, stretch, use brace

Step 6 of rigor mortis

During rigor mortis, the membrane of muscle cell will become more permeable to calcium ions, which causes an influx of these ions into the cell. With death, there is little to no ATP produced, so as the calcium ions bind with troponin and allow myosin and actin to bind, there will be no ATP to detach the myosin and actin. This results in constant contraction, which makes the muscles seem stiff

Given the placement of the radial nerve, what type of muscles does this nerve most likely stimulate?

Extensor because it's on the dorsal side and muscles can only pull and shorten

Look at where the ulnar nerve runs in the arm. What type of forearm muscle does this nerve stimulate? Explain.

Flexor because on ventral surface and muscles can only pull and shorten

Step 5 of rigor mortis

Relaxation will occur when stimulation of the nerve stops. Calcium is pumped back into the sacroplasmic reticulum and stops the binding between actin and myosin. This can also occur due to the lack of ATP

Step 3 of rigor mortis

The calcium then floods into the muscle cell and binds with troponin, which moves the trypomysin (the protein that block myosin) and allows actin and myosin to bind. The actin and myosin cross bridge uses ATP as an energy source to disconnect. ATP hydrolyze and turn into ADP and P

Why did we observe the elbow joint of a cow? Why is a cow elbow different structurally from your elbow?

The connecting bones are the same - ulna, radius, and humerus. The difference in the bones is that in a cow the ulna and radius become fused whereas in a human they are two distinct bones with a space in between

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

The contraction of the muscle doesn't occur whenever we consciouly desire them to move. How the esophagus gets food to the stomach, heart, digestion, breathing (still down when sleeping), blinking

How do bones, muscles, and joints work together to move the body?

The muscles pull on bones to make them move and joints enable their flexibility

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

The myosin and actin in the sarcomere pull the muscle fibers together, so the fibers themselves shorten, but the myosin and actin slide past each other. Lots of sarcomeres in muscle cells all slide, allowing the muscle to shorten

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 are involved in moving the human machine?

The nervous system is involved in moving the human machine because in order to move, neurons must transmit signals between different parts of the body.

Take a look at the temporalis, one of the face muscles you built in unit 1. Using what you have learned about muscles and their attachments, describe the origin and the insertion of this muscle. How is this structure linked to the function?

The origin of the temporalis is the temporal fossa on the temporal bone of the skull. The insertion is the coronoid process of the mandible. With the origin pulling the insertion, the function of this muscle is to retract (move back) and elevate the mandible during the chewing motion

How is the location of the nuclear nerve lined to the pain you feel when you hit your funny bone? Why is this nerve so vulnerable?

There is only skin and fat 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

What can put a worker at risk of carpal tunnel syndrome

anything computer (ie: student, teacher)

pectoralis major sternal head example

arm westling

the smooth, white tissue that covers the ends of bones where they come together to form joint

articular cartilage

hips and shoulder

ball and socket joint movement

loops around the carpal

carpal tunnel

a soft, gel-like padding between bones that protects joints and facilitates movement

cartilage

histology of smooth muscle

cells stick together to form gap junctions, they are spindle shaped and have the central (single) nucleus

moving a part so that its end follows a circular path

circumduction

Using your knowledge of tissues, what type of tissue makes up the three layers of member you encountered in you muscle?

connective

muscle tissue in which the contractile (contraction) fibrils in the cells area aligned in parallel bundles, so that their different regions form stripes visible in a microscope

striated muscle

Freely moveable joint that, combined with oily fluid filled cavity, separates the bones that allow us to swing our arms or jump up and down

synovial joints

a band of tissue that connects muscle to bone

tendons

elbows and knees

hinge joint examples

permits back and forth movements

hinge joint movement

convex surface of one bone fits into the concave surface of another

hinge joint structure

excess extension of the parts at a joint beyond anatomical position

hyperextension

After a few years, your goniomoter breaks. How else can a clever HBS student measure range of motion?

protractor

abduction v

v adduction

rotation v

v circumduction

plantar flexion v

v dorsiflexion

depression v

v elevation

flexion v

v extension

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

Muscles in the forearm that extend and control movement of the fingers (muscles pull, not push)

Muscle rule #1

Muscles must have at least 2 attachments and must cross at least 1 jiont

serratus anterior ex

Push ups

process of sarcomeres sliding past each other

the sliding filament mechanism of muscle contraction

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

ACH travels across neuromuscular junction, binds to sarcolemma (cell membrane of muscle cells), tells potassium channels to open, then open sodium channels, sending action potential through the tubules and releasing calcium

Step 4 of rigor mortis

ATP is then re-synthesized to allow actin and myosin to continue this process, allowing movement of the muscle. The myosin and actin will continue to bind and rebind

Think about the action of the muscle you have built. Describe at least two exercises that will strengthen the muscles of the chest. Make sure to not the specific muscles that are targeted to each exercise.

Abdominal: sit ups Pectoralis minor: shoulder girdle stretch

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

After death, calcium will be released and flow into muscle cells allowing action and myosin to continue contracting. ATP will no longer be produced due to the lack of brain activity so the actin and myosin won't be able to break a part and continuously contraction will occur, making the muscles stiff. It is a temporary state because the body will eventually begin to decay which will cause all body actions to stop.

What does it mean to have a dislocated shoulder?

It means the entire ball in the shoulder joint (ball and socket joint) is out of the socket.

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?

It produces heat because muscles generate a lot of heat

What factors influence range of motion of a joint?

Joint structure (double jointed - loose joint; type of joint; genetics - how its formed), ligaments (tighter), tendons (tighter), muscles, skin, tissues injury, fact (or adipose) tissue, body temperature, activity level, age, and sex all influence an individual's range of motion about a joint

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?

Lack of oxygen, can't make ATP: stop what doing and breathe deeper Run out of ATP: break glycogen or burn fat if no glucose to make ATP Run our of potassium, sodium, or calcium ions Dehydration: can re-synthesize ATP

Your mom comes back from the doctor and says she has pulled her tibialis anterior. She knows you are taking HBS and asks you to tell her about her injury. Based on what you have learned, what can you deduce about this muscle and her injury?

Located around the front of her tibia bone

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

Muscle rule number 2 is that muscles always pull and get shorter. This means that the muscles didn't return to the former length because there would need to be an opposing bone or tendon pulling it in the other direction in order for it to become long and ready to pull again.

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

Nervous - action potential Muscular - muscle fibers contract Skeletal - bone moves Digestive - ATP Respiratory - need oxygen to break down food in the mitochondria

Step 2 of rigor mortis

Next, the sarcoplasmic reticulum, which is a type of smooth ER that regulates the calcium ion concentration in the cytoplasm of striated muscle cells, is stimulated to release calcium into the muscle cell

Explain how you know which attachment of muscle is in the origin and which attachment is the insertion

Origin - the muscle that stays stationary (more proximal) Insertion - the muscle that moves (more distal)

Explain how the muscles pectoralis major and serratus anterior show 2 different ways to which muscles are named

Pectoralis major is a method naming muscles based on size. This muscle is very large, hence "major" Serratus anterior is a method naming muscles based on shape, serratus meaning teeth of saw, but also location, anterior meaning front of the body

How does your range of motion compare to the range of motion of other groups. Why are differences most likely to occur?

People have a difference range of flexibility, tissues (thick arms), past injuries, diseases

How are tendons and ligaments similar in both structure and function? How are they different in both structure and function?

They are similar because they are both white fibrous tissue that work to improve and control motion. They are different because a tendon is tougher and thicker. Tendons also attach muscles to bones, pulling the bone when the muscle contracts, enabling movement. Ligaments attach bone to bone. They are more elastic and help hold structures together and keep them stable

What would happen to a person's ability to use their arm if the radial nerve were damaged? What about the wrist?

They might have difficulty extending the arm at the elbow, or they may have trouble extending their wrist or fingers

moving a part away from the midline

abduction

any muscle that pulls a body part away from the midline

abductors

flexor carpi ulnaris and extensor digitorum longus

actions

Are the muscles of pectoralis major adductors of abductors

adductor because it pull the arms into the midline

any muscle that pulls a body part toward the midline

adductors

Explain to your client why you need multiple exercises to effectively build and tone the muscles of the chest

each exercise uses and builds a specific muscle

straightening parts at the joint so that the angle between them increases

extension

location of smooth muscle

lines blood vessels and hollow organs, such as the stomach,, intestine, and bladder

frontalis and temporalis

location

travels between the radius and ulna, and ends at the tip of the middle finger

median nerve

function of smooth muscle

movement of blood through vessels, food through digestive system

function of skeletal muscle

movement, heat, posture

Muscle rule #6

muscle striations point to the attachments and show the direction of pull

muscles whose action is normally controlled by an individual's will

muscle under voluntary control

Muscle rule #2

muscles always "pull" and get shorter (not push and get longer)

Muscle rule #5

muscles work in opposing pairs

__________ is thick filament and _________ is thin filament

myosin; acting

biceps brachii and triceps brachii

number or origins

sternocleidomastoid and brachioradialis

origin and insertion

A W shape branch of nerve connects to a V on C4 and C5 and a straight on C6, travels under the clavicle, down the armpit, down the dorsal side of the humerus, moves to the front to pass through the antecubital region (where they draw your blood), runs down the medial side of the radius 1/4 of the way, then on the dorsal side, then it branches into each digit on the back of the palm (it also branches from the humerus to the tricep medial heads)

radial nerve

different ways in which muscles can be named

shape, size, location, direction, actions, origin and insertion, number of origins

external intercostal ex

sighing

pectoralis major abdominal example

sit ups

gluteus maximus and gluteus minimus

size

muscle(s) that are voluntary

skeletal

describe the structural differences in three 3 types of muscle tissues

skeletal - striated; multinuclear (more than one nucleus) Smooth - not striated, thin Cardiac - striated; branched (can see distinct lines) under microscope, intercalated discs (at top and bottom of branches that help reinforce the weak branches)

muscle(s) that have striations

skeletal and cardiac

Types of muscles

skeletal, smooth, cardiac

muscle(s) that don't have striations

smooth

muscle(s) that aren't voluntary

smooth and cardiac

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

the electrical signal travels down a motor neuron toward a muscle cell. The signal is transferred to the sarcoplasmic reticulum. Once the signal reaches the SR, calcium is released, which starts the process of muscle contraction.

Describe how problems at the carpal tunnel can lead to pain and discomfort

the median nerve which controls sensation and movement in the thumb and first three fingers, runs through this passageway along with tendons to the fingers and thumb. When it's pinched or compressed, the result is numbness, tingling, weakness, or pain in the head