Chapter 6-The Human Body Flashcards
What does the musculoskeletal system provide the body with?
Movement Organ protection Upright posture Form Heat
Define musculoskeletal system
The bones and voluntary muscles of the body
What are the three types of muscle?
Skeletal (voluntary), Cardiac (involuntary), and smooth (both voluntary and involuntary)
What makes cardiac muscle unique?
It can create and conduct its own electrical impulses
What are two other terms for skeletal muscle?
Voluntary or striated muscle
How do muscles interact to allow us to move in a slow and controlled manner?
Antagonistic pairs such as the biceps and triceps control each other’s motion so that we can move our limbs in a slow and controlled manner
How many skeletal muscles are in the musculoskeletal system?
Over 600 muscles
What structures hold the lungs in place?
The trachea, pulmonary ligaments, and vessels
How are lungs further subdivided into parts?
Lung–>lobe (3R/2L) each with its own bronchus that comes from the carina at the base of the trachea, bronchus–>bronchiole–>alveoli
Where does gas exchange occur?
In the alveoli, whose walls are filled with pulmonary capillaries that carry CO2 from the right ventricle and O2 to the left atrium once gas exchange occurs
What system of membranes assists the diaphragm in breathing?
The visceral pleura and parietal pleura which contain between the the fluid-filled pleura space
What are the two functions of the respiratory system?
Ventilation (mechanically moving air into and out of the lungs) and respiration (gas and nutrient exchange via diffusion through the walls of capillaries)
What is another name for the pleural space?
potential space because there shouldn’t actually be any empty space between the membranes unless the patient has sustained an injury
How do the visceral and parietal membranes assist with breathing?
The serous fluid in the potential space created a surface tension between the visceral and parietal pleura, which causes them to pull on the lungs to expand them when the chest cavity expands
What is the primary muscle of breathing?
The diaphragm
Is the diaphragm voluntary or involuntary muscle?
Both, we can temporarily change our natural pattern of breathing (e.g. hold our breath, breath slower/faster, etc.) but at a certain point, if the CO2 levels in our lungs gets too high, our brain will start to control our diaphragm and force us to breath in a regular patter, at which point it becomes an involuntary muscle
What is the next most important muscle in breathing that assists the diaphragm?
The intercostal muscles
How do the diaphragm and the intercostal muscles work together to achieve ventilation?
The diaphragm contracts to expand the thoracic cage vertically and the intercostal muscles contract to expand the thoracic cage horizontally. The overall increase in volume of the lungs results in a reduced pressure, which causes air to be sucked in
What term describes the mechanism of breathing by expanding the lungs?
Negative pressure breathing
What are the accessory muscles of breathing and when might they get involved?
Cervical (neck) muscles, pectoral muscles, and abdominal muscles might get involved in breathing if the airway is obstructed
What are the normal respiratory rates for adults, children, and infants?
Adults: 12-20 breaths/min
Child: 12-40 breaths/min
Infant: 30-60 breaths/min
Define circulatory/cardiovascular system
The arrangement of arteries, arterioles, capillaries, venuoles, and veins that move blood, oxygen, nutrients, and cellular waste throughout the body
What are the two circuits of the cardiovascular system?
Systemic (carries blood back and forth between the body and heart) and pulmonary (carries blood back and forth between the lungs and heart)
What are the normal heart rates for adults, children, and infants? FINISH
Adults: 60-100 bpm
Children:
What does the stroke volume refer to and what is a normal range for SV?
SV is the amount of blood that is pumped from the heart with each pump, and it should be arounf 70-80 mL
What is cardiac output?
The amount of blood moved throughout the body in one minute
How do you calculate cardiac output?
Heart rate times stroke volume
What are arteries made of?
Circular muscle and elastic tissue
What types of tissue need a constant supply of blood?
Kidney, heart, brain
What types of tissue don’t need a constant supply of blood?
Skin, muscles in the extremities, and intestines
How do arteries change their diameter?
The tunica media is the middle layer of arteries made up of smooth muscle that contracts to reduce the diameter of the arteries
Where can pulses be felt most easily?
In large arteries near the surface of the skin that can be pushed up against hard structures such as bone
Where can a central pulse be taken?
Carotid and femoral arteries
Where can a peripheral or distal pulse be taken?
Brachial, radial, dorsalis pedis, or posterior tibial arteries
Define blood pressure
The pressure exerted against the walls of arteries by the pumping of the heart
Define systole
The phase of the heart beat in which the left ventricle contracts
Define diastole
The phase of the heart beat when the left ventricle is relaxed and filling with blood
Systole and diastole are the crests and troughs of the _____
Pulsatile pressure wave
How can you measure systole and diastole?
A sphygmomanometer or bp cuff
What units are systolic and diastolic bp reported in?
mm Hg (millimeters of mercury)
What is perfusion?
The circulation of blood through an organ/tissue in an adequate amount needed to support cells’ needs
What is shock?
When the amount of blood flow through an organ/tissue is inadequate to support the cells’ needs
What is another term for shock?
Hypoperfusion
How does the body react when a significant amount of blood has been lost?
Vessels constrict to accommodate the reduced volume of blood while maintaining the proper blood pressure, and the heart beats faster to maintain cardiac output
Define digestive system
The system of organs responsible for digestion, or the processing of food that nourishes cells
What types of organs are housed in the abdominal cavity?
Organs of digestion and excretion
What organs are found in the right upper quadrant of the abdomen?
Liver, gallbladder, part of the colon, and part of the pancreas
What organs are in the left upper quadrant?
The stomach, spleen, part of the colon, and part of the pancreas
What organs are in the right lower quadrant?
Appendix, part of the urinary bladder, and cecum and ascending portions of the colon
What organs are in the left lower quadrant?
The descending and sigmoid colon and part of the urinary bladder
What are the retroperitoneal organs?
The kidneys and pancreas because they’re behind the abdominal cavity
What organ occupies all four quadrants?
Small intestine
What does pathophysiology refer to?
How normal physiological processes are impacted by diseases (e.g. diabetes is an illness of the pancreas and pneumonia is a disease of the lungs, and stroke is a disease of the brain)
What are two common emergencies that EMTs respond to?
Respiratory compromise and shock
