Human Anatomy and Physiology Circulatory System (copy)

The circulatory system transports oxygen and removes CO2, essential for homeostasis and cellular respiration.

Key organs:

• Heart: pumps blood

• Arteries: carry oxygenated blood (except pulmonary artery)

• Veins: carry deoxygenated blood (except pulmonary vein)

• Lungs: oxygenate blood, remove CO2

• Blood: red blood cells (oxygen), white blood cells (immunity), platelets (clotting), plasma (liquid)

Pulmonary circulation: Brings blood to the lungs and back

• Inferior Vena Cava - Right Atrium - Tricuspid Valve - Right Ventricle - Pulmonary Valve - Pulmonary Artery - Lungs

Systemic circulation: Brings oxygenated Blood to the rest of the body

• Lungs - Pulmonary Vein - Left Atrium - Mitral Valvce - Left Ventricle - Aortic Valve - Aorta

Arteries: thicker walls, higher pressure, carry oxygenated blood from the heart

Veins: Thinner walls, valves, and veins carry oxygen-depleted blood back to the heart.

Blood components:

• Red blood cells (RBCs):

  • Carry oxygen, remove CO2

  • Anemia: too few RBCs

• White blood cells (WBCs):

  • Fight germs

  • Imbalances: infection, leukemia, weak immune system

• Platelets:

  • Stop bleeding

  • Imbalances: excessive bleeding, dangerous clots

• Plasma:

  • Liquid carrying cells, nutrients

  • Aids wound healing

The respiratory system facilitates oxygen intake and CO∗2 expulsion via alveoli.

• Major organs:

  • Nose/Mouth: Entry and exit points for air, with the nose filtering and humidifying incoming air.

  • Pharynx: Connects the nasal and oral cavities to the larynx.

  • Larynx: Voice box containing vocal cords, essential for speech.

  • Trachea: Windpipe that carries air to the lungs.

  • Bronchi: Two main branches of the trachea that lead into the lungs.

  • Lungs: Primary organs for gas exchange.

  • Alveoli: Tiny air sacs in the lungs where oxygen and carbon dioxide exchange occurs.

• Functions:

  • Oxygen Intake: Delivers oxygen to the bloodstream for cellular respiration.

  • Carbon Dioxide Removal: Eliminates carbon dioxide, a waste product of metabolism.

  • Regulation of Blood pH: Assists in maintaining the acid-base balance in the body.

  • Voice Production: Enables speech through the movement of air over the vocal cords.

• Diffusion of Gases:

  • Oxygen diffuses from the alveoli into the blood due to a higher concentration of oxygen in the alveoli compared to the blood.

  • Carbon dioxide diffuses from the blood into the alveoli due to a higher concentration of carbon dioxide in the blood compared to the alveoli.

  • This exchange is driven by the concentration gradient of each gas.

Breathing:

• Inhalation: diaphragm contracts, ribs expand

• Exhalation: diaphragm relaxes, ribs squeeze

• Gas exchange: Oxygen enters blood, CO2 exits.

The nervous system controls body functions via electrical signals.

• Sensory input: Gathers information

• Processing: The Brain decides actions

• Motor output: Sends commands

Key parts:

• Central nervous system (CNS): The Brain and spinal cord, makes decisions, controls movements -Brain Lobes:

  • Frontal Lobe: Responsible for cognitive functions such as planning, decision-making, memory, and personality.

  • Parietal Lobe: Processes sensory information including touch, temperature, pain, and spatial awareness.

  • Temporal Lobe: Involved in auditory processing, memory formation, and language comprehension.

  • Occipital Lobe: Primarily responsible for visual processing.

• Peripheral nervous system (PNS): Nerves carrying signals to/from CNS
  -Somatic System: Controls voluntary movements of skeletal muscles.
  -Automatic System: Regulates involuntary functions such as heart rate, digestion, and breathing