a+p: systems

What components make up the musculoskeletal system?

Skeleton, ligaments, muscles, tendons, and other connective tissues

What are the four main functions of the skeletal system?

Shape, protect internal organs, allow movement, store minerals and produce blood cells

What are the six components of the skeletal system?

Skull, spinal column, thorax, pelvis, upper and lower extremities

How are bones classified?

By size and shape: long, short, flat, or irregular

What are the two parts of the skull?

Cranium and face

What bones make up the cranium?

Occipital, two parietal, two temporal, and the frontal bones

What is the structure of the cranium?

Thick, tough outer layer and a thinner, brittle inner layer

Why can brain injuries occur despite the skull's protection?

Due to bony projections and ridges

What can bleeding and swelling in the cranium cause?

Increased pressure, unresponsiveness, or death

How many bones are in the face?

14 bones; 13 immovable, 1 movable (mandible)

What is the only movable bone in the face?

Mandible

What is the function of the spinal column?

Main body support; protects spinal cord

What connects vertebrae together?

Strong ligaments

What can vertebrae damage affect?

Spinal cord: may be squeezed, stretched, torn, or severed

How many vertebrae are in the spinal column?

33 vertebrae

What are the five parts of the vertebral column?

Cervical, thoracic, lumbar, sacral, coccyx

How many ribs are in the thorax?

24 ribs (12 pairs)

What is the difference between true, false, and floating ribs?

True: first 7 pairs, False: next 3 pairs, Floating: last 2 pairs

What structures form the pelvis?

Sacrum and coccyx

What bones make up the lower extremities?

Femur, tibia, fibula, patella, tarsals, metatarsals, phalanges

What bones make up the upper extremities?

Clavicle, scapula, humerus, radius, ulna, carpals, metacarpals, phalanges

What are the types of joints?

Immovable, slightly movable, movable

What are the types of movable joints?

Ball-and-socket, hinge, pivot, gliding, saddle, condyloid

Why can bone fractures lead to shock?

Because bones are living tissues with a rich blood supply

What are the three types of muscles?

Skeletal, smooth, and cardiac

What type of muscle enables deliberate movement?

Skeletal muscle

What type of muscle performs automatic functions?

Smooth muscle

What muscle has automaticity?

Cardiac muscle

How does cardiac muscle differ structurally?

Smooth like smooth muscle, striated like skeletal, with a unique meshwork

What supplies the cardiac muscle with blood?

Coronary arteries

What happens if cardiac muscle loses blood supply?

It cannot tolerate even brief interruptions

What are the main functions of the respiratory system?

Respiration, ventilation, oxygenation, acid-base balance

What is respiration?

Movement of oxygen and carbon dioxide across membranes

What is ventilation?

Mechanical process of moving air in and out of the lungs

What is oxygenation?

Movement of oxygen molecules from high to low concentration areas

How does the respiratory system help regulate pH?

By adjusting respiration rate and depth to manage CO2 levels

What structures are in the upper airway?

Nasal cavity, pharynx, larynx

What structures are in the lower airway?

Trachea, bronchi, bronchioles, alveoli

What does the nasal cavity do?

Cleanses, warms, and humidifies air

What does the pharynx do?

Directs air to trachea and food to esophagus

What does the larynx contain?

Vocal cords and protects airway during swallowing

What supports the trachea?

C-shaped cartilaginous rings

What are bronchi and bronchioles?

Branching airways leading to alveoli

What happens in the alveoli?

Gas exchange between oxygen and carbon dioxide

What is surfactant?

Substance that reduces surface tension in alveoli

What happens without surfactant?

Alveoli collapse and respiratory failure can occur

What covers the lungs?

Visceral pleura

What covers the chest wall?

Parietal pleura

What is the pleural cavity?

Space between pleura with negative pressure keeping lungs inflated

What muscle is essential for breathing?

Diaphragm

How do infant airways differ from adults?

Smaller nose/mouth, larger tongue, softer trachea

Why do infants rely on the diaphragm more?

Due to immature chest muscles

What are signs of airway obstruction in infants?

Nasal flaring, seesaw breathing, head bobbing

What nerve controls the diaphragm?

Phrenic nerve (C3-C5)

What can injury to C3–C5 cause?

Diaphragm paralysis

What are mechanics of inhalation?

Diaphragm/intercostals contract, thoracic volume increases

What are mechanics of exhalation?

Diaphragm/intercostals relax, thoracic volume decreases

What is adequate breathing characterized by?

Normal rate, tidal volume, rhythm, sounds, and chest expansion

What are normal respiratory rates for adults?

8–24 breaths per minute

What are signs of inadequate breathing?

Irregular rate, shallow depth, abnormal sounds, accessory muscle use

What is the diaphragm's contribution to breathing?

60–70% of effort

What happens during gas exchange?

Oxygen enters blood, CO2 exits into alveoli

How is CO2 mainly transported?

As bicarbonate in the blood

What is pulmonary circulation?

Blood flow between heart and lungs

What is systemic circulation?

Blood flow between heart and body tissues

What are the components of the circulatory system?

Heart, blood vessels, and blood

What is the function of the circulatory system?

Transport oxygen, nutrients, and waste

What are the heart's four chambers?

Two atria and two ventricles

How does blood flow through the heart?

Right atrium → tricuspid valve → right ventricle → pulmonary valve → lungs → left atrium → mitral valve → left ventricle → aortic valve → body

What is the heart's conduction system?

SA node, AV node, bundle of His, Purkinje fibers

What do arteries do?

Carry blood away from the heart

What are examples of major arteries?

Aorta, coronary, carotid, femoral, brachial, radial, pulmonary

What are arterioles?

Small branches of arteries leading to capillaries

What occurs in capillaries?

Exchange of gases, nutrients, and waste

What are venules?

Small vessels that collect blood from capillaries

What do veins do?

Carry blood back to the heart

What veins carry oxygen-rich blood?

Pulmonary veins

What do valves in veins do?

Prevent backflow of blood

What does the superior vena cava do?

Carries blood from upper body to right atrium

What does the inferior vena cava do?

Carries blood from lower body to right atrium

What is the function of red blood cells?

Carry oxygen and carbon dioxide

What is hemoglobin?

Protein in RBCs that binds oxygen and carbon dioxide

What is the function of white blood cells?

Defend against infection

What is the function of platelets?

Help in blood clotting

What is plasma?

Liquid part of blood carrying cells, nutrients, and waste

What does albumin in plasma do?

Helps retain water in blood vessels

What is a pulse?

Wave of pressure from heart contraction felt in arteries

What are central pulses?

Carotid and femoral

What are peripheral pulses?

Radial, brachial, dorsalis pedis, posterior tibial

What is an apical pulse?

Pulse felt over left ventricle

What is blood pressure?

Force exerted by blood on artery walls

What is systolic pressure?

Pressure during heart contraction

What is diastolic pressure?

Pressure during heart relaxation

What affects diastolic pressure?

Vessel diameter

What is hydrostatic pressure?

Force pushing fluid out of capillaries

What is perfusion?

Delivery of oxygen and nutrients, removal of waste via blood

What is shock (hypoperfusion)?

Inadequate supply of oxygen and nutrients to cells

How is oxygen transported?

97% by hemoglobin, 3% dissolved in plasma

How is carbon dioxide transported?

70% as bicarbonate, 23% on hemoglobin, 7% in plasma

What happens during anaerobic metabolism?

Less energy is produced, and acid builds up