Pathways

Pathway of Oxygen into the Lungs

  • External Environment to Lungs

    • Oxygen enters through the nose or mouth
    • Travels through the pharynx, larynx, and trachea
    • Moves into the bronchi, branching into smaller bronchioles
    • Finally reaches alveoli where gas exchange occurs with blood

  • Carbon Dioxide/Waste Removal

    • CO2 diffuses from the blood into alveoli
    • Exhaled through the respiratory tract in reverse order of inhalation

Mechanics of Breathing

  • Inhaling (Inspiration)

    • Diaphragm contracts and moves downward
    • Intercostal muscles contract, expanding the rib cage
    • Creates negative pressure in chest cavity, drawing air in

  • Exhaling (Expiration)

    • Diaphragm relaxes, moving upward
    • Intercostal muscles relax, rib cage lowers
    • Positive pressure forces air out

Lung Volumes Investigation

  • Plan and conduct experiments measuring different lung volumes:
    • Tidal Volume: air inhaled/exhaled at rest
    • Vital Capacity: maximum amount of air expelled after deepest breath
    • Residual Volume: air remaining after exhalation

Nutritional Components for Homeostasis

  • Essential Nutritional Components:
    • Carbohydrates: primary energy source
    • Proteins: building blocks for tissues
    • Lipids: long-term energy storage
    • Vitamins & Minerals: support various biochemical functions
    • Water: crucial for all bodily functions

Pathway of Food Through the Gastrointestinal Tract

  1. Mouth

    • Mechanical digestion (chewing) and enzymatic digestion (saliva) begin.

  2. Esophagus

    • Food moves via peristalsis to the stomach.

  3. Stomach

    • Churning food and mixing with gastric juices (HCl, pepsin).

  4. Small Intestine

    • Further digestion/absorption occurs (duodenum, jejunum, ileum).

  5. Large Intestine

    • Absorbs water, forms waste for elimination.

  6. Rectum and Anus

    • Storage and expulsion of feces.

Accessory Organs of the Digestive System

  • Salivary Glands: Produce saliva to assist in digestion.
  • Liver: Produces bile; processes nutrients.
  • Gallbladder: Stores and concentrates bile.
  • Pancreas: Secretes digestive enzymes.

Male and Female Reproductive Systems

  • Male System:

    • Testes produce sperm and male hormones (testosterone).
    • Sperm travels through the vas deferens to the urethra for ejaculation.

  • Female System:

    • Ovaries produce eggs and female hormones (estrogen, progesterone).
    • Egg travels through the Fallopian tube; fertilization occurs here.

Pathway of Fertilization

  • Sperm Meets Egg:
    • Sperm travels through the cervix and uterus to the Fallopian tube.
    • Fertilization occurs when sperm penetrates the egg.

Supporting Structures for Pregnancy

  • Uterus: nurtures and supports the embryo.

  • Placenta: provides nutrients and removes waste.

  • Amniotic Sac: cushions the embryo/fetus.

  • Changes During Pregnancy:

    • Hormonal shifts to maintain pregnancy and prepare for childbirth.
    • Physical changes to accommodate fetal growth.

Process of Childbirth

  • Labor Process:
    • Contractions of the uterus dilate the cervix.
    • Baby is pushed through the birth canal.

Urinary System Functions

  • Blood Filtration:

    • Kidneys filter blood to remove waste, producing urine.

  • Pathway of Urine Out of the Body:

    • Urine formed in the kidneys
    • Flows through ureters to the urinary bladder
    • Stored until expelled through the urethra

Practice and Review

  • Utilize images to label:

    • Pathways of food, air, blood/urine, eggs/sperm.

  • List functions of organs in respiratory, digestive, reproductive, and urinary systems.

  • Study using success criteria to guide understanding of physiological processes.