Science Class: Nutrient Transport in the Body

Jun 25, 2024

Science Class: Nutrient Transport in the Body

Overview

  • Discussion on nutrient transport in two organ systems: Respiratory System and Circulatory System.

Respiratory System

  • Function: Responsible for taking in oxygen and expelling carbon dioxide.
  • Also known as the human breathing system.

Parts of the Respiratory System

  1. Nose and Mouth: Entry points for oxygen.
  2. Nasal Cavity/Passageways: Air is warmed, dampened, and cleansed of particles.
  3. Pharynx: The throat.
  4. Larynx: The voice box.
  5. Trachea: Also known as the windpipe; passageway for air into the lungs.
  6. Lungs: Main organs of the respiratory system; humans have a pair of lungs (right and left).
  7. Bronchi: Two branching tubes connecting the trachea to the lungs.
  8. Bronchioles: Hair-like tubes connecting to the alveoli, where gas exchange happens.
  9. Alveoli: Site of gas exchange.

Breathing Process

  • Inhalation: Oxygen enters, ribs move out, chest space increases, diaphragm contracts (moves down).
  • Exhalation: Carbon dioxide exits, ribs move in, chest space decreases, diaphragm relaxes (moves up).

Circulatory System

  • Function: The life support structure that nourishes cells by delivering materials throughout the body.
  • Also known as the cardiovascular system.

Major Parts of the Circulatory System

  1. Heart: Pumps blood throughout the body; main organ of the system.
  2. Blood Vessels: Carry blood throughout the body. Three types:
    • Arteries: Carry blood away from the heart.
    • Veins: Carry blood towards the heart.
    • Capillaries: Smallest blood vessels; site of gas and nutrient exchange.
  3. Blood: Carries materials throughout the body.

Heart Details

  • Size of a fist.
  • Four chambers: Two atria (receiving chambers) and two ventricles (pumping chambers).
  • Valves: Prevent blood from flowing backwards; function like one-way doors.
  • Blood Flow:
    • Deoxygenated blood enters through superior and inferior vena cava → right atrium → tricuspid valve → right ventricle → pulmonary valve → pulmonary artery → lungs (to get oxygen).
    • Oxygenated blood enters through pulmonary vein → left atrium → bicuspid valve → left ventricle → aortic valve → aorta → body.

Interaction Between Respiratory and Circulatory Systems

  • Air enters lungs → left part of the heart → bloodstream → body.
  • Heart pumps blood to transport nutrients and oxygen to cells.
  • Cells use oxygen to process nutrients and release energy, producing carbon dioxide.
  • Carbon dioxide is delivered to the right portion of the heart → lungs → exhaled.

Types of Circulation

  1. Pulmonary Circulation: Movement of blood from heart to lungs and back to heart.
  2. Coronary Circulation: Movement of blood through the tissues of the heart.
  3. Systemic Circulation: Movement of blood from heart to rest of body (excluding lungs).

[Music] END