JBLearning EMT Chapter 6

Musculoskeletal system

The bones and voluntary muscles of the body. (Provides shape, upright posture, and movement, protects vital organs)

muscles

Form of tissue that allow body movement

3

How many types of muscle are there?

Skeletal muscle

Muscle that attaches to the bones of the skeleton

Smooth muscle

Muscle that is found within blood vessels and intestines

Cardiac muscle

Muscle that is only found within the heart and can create and conduct its own electrical impulses

Because they are under direct control of the brain

Why are skeletal muscles also known as voluntary muscles?

Antagonistic pairs of muscles

How are you able to control the movement of muscle without losing control? (Eg moving your arm and slapping yourself by accident)

Trachea, arteries and veins, and pulmonary ligaments

How are the lungs held in place?

Each lung is divided into lobes, and then segments

How are the lungs divided?

3: upper, middle, and lower

How many lobes does the right lung have?

2: upper and lower

How many lobes does the left lung have?

Bronchus

What branches off from the trachea in the lung?

Bronchioles

What branches off from the bronchus?

Aveioli; where o2 and co2 are exchanged; functional unit of the respiratory system

What branches off from the bronchioles and what do they do?

Pulmonary capillaries; carry o2 from the body to the lungs and co2 from the lungs to the body

What do the walls of the aveioli contain and what do they do?

Assists in expansion and contraction of the lungs; visceral pleura covers the lungs and parietal pleura lines the chest wall

What is pleura and where is it located?

Pleura layers are hell together tightly with a thing film of fluid, and it pulls the lungs so that they expand during inhalation

How does pleura work?

Diaphragm

What is the primary breathing muscle?

Separates the thorax and the abdomen; acts like a voluntary muscle while still performing automated functions

What are characteristics of the diaphragm?

Cervical (neck), abdominal, pectoral, and intercostal muscles

What other muscles are involved in breathing?

Intercostal muscles contract, moving the ribs up and down, the diaphragm contracts and lowers, enlarging the thoracic cage

What happens during inhalation?

As the chest cavity enlarges, pleural pressure drops, sucking air into the lungs

What is negative pressure breathing?

Diaphragm and intercostal muscles relax, shrinking chest cavity, pushing air out of lungs

What happens during exhalation?

Pectoral and abdominal muscles are used in breathing

What muscles are used in addition when the airway decreases?

12 to 20 breaths per minute

What is the normal breathing range for adults?

12 to 40 breaths per minute

What is the normal breathing range for children?

30 to 6o breaths per minute

What is the normal breathing range for infants?

Agonal gasps

Brian continues to send signal to breathing muscles resulting in short and shallow breaths

60-100 bmp

What is the normal resting heart rate for adults?

180 bpm

What can the heart rate rise to during physical activity?

70 to 80 mL

How much blood is pumped during one heart beat (adult)?

Stroke volume

Amount of blood moved in one beat

5 to 6 L

How much blood is pumped in one minute?

Cardiac output

Amount of blood pumped in one minute

CO = HR x SV

Cardiac output formula

Arteries

Carry blood from heart to all body tissues

Arterioles

What branches off from arteries?

Fine circular muscles tissue and sometimes elastic tissue

What are arteries made of?

Contract

What do arteries do to accommodate for loss of blood volume and increase blood pressure?

Tunica media

The middle layer of arteries (smooth layer that can contract to dilate and change diameter of vessel)

Aorta

Main artery leaving the back left side of the heart and carries oxygenated blood to body

Pulmonary artery

Begins at right side of heart and carries oxygen-depleted blood to lungs

Carotid (neck) and femoral (groin)

What are the central pulses and where are they located?

Radial artery (wrist), brachial artery (arm) , posterior tibial (medial malleus), and dorsalis pedis (foot)

What are the peripheral pulses and where are they located?

Blood pressure

Pressure blood exerts against the walls of arteries as it passes through them

Systole

When the cardiac muscle of left ventricle contracts ad pumps blood into the aorta

Diastole

When the muscle of ventricle relaxes and fills with blood

Blood pressure cuff

How can high and low points of blood pressure be measured?

Nervous system

Most complex organ system

Brain and spinal cord

What are the two major structures of the nervous system

Fundamental functions; heart rate, breathing, blood pressure

What is the nervous system responsible for?

Central Nervous System (CNS)

Brain and spinal cord

Peripheral nervous system (pns)

Nerves outside the brain and spinal cord that connect the CNS to the rest of the body

Somatic nervous system

Regulates activities where there is voluntary control (eg walking)

Automatic nervous system

Controls body functions without voluntary control

Pathophysiology

Study of how physiologic functions are affected by disease

Abdomen

What is the second major body cavity?

Thick muscular walls anterior and posterior

What surrounds the abdominal cavity

Liver, gallbladder, and part of the colon

What organs are in the right upper quadrant of the abdomen?

8th and 12th

What ribs is the liver protected by?

Stomach, spleen, and part of colon

What organs are in the left upper quadrant of the abdomen?

Descending and sigmoid portions of the colon

What organs are in the left lower quadrant of the abdomen?

Two portions of large intestine and ascending colon

What organs are in the right lower quadrant of the abdomen?

Retroperitoneal

The kidneys and pancreas are this because they are behind the abdominal cavity

Front of the body

Anterior

Back of the body

Posterior

Side of the body

Lateral