Chapter 16 pptx-Mekyle

• Medical science initially relied on superstition and magic.
• Observations of injuries, wound healing, and cadavers led to advancements.
• Experimentation and anatomical/physiological terminology arose later on.
• Knowledge of the human body increased by studying corpses and performing dissections.

Anatomy & Physiology

• Anatomy studies the structure and morphology of the human body and is derived from the Greek language.
• Physiology studies the functions of the human body.
• The structure of body parts influences their function.

Levels of Organization

• All materials, living or non-living, consist of atoms made up of chemicals.
• Subatomic particles are the protons, neutrons, and electrons that make up cells.
• Atoms are tiny particles that make up chemicals like hydrogen and carbon.
• Molecules are particles consisting of atoms joined together like water and glucose.
• Macromolecules are large particles made up of molecules like DNA and protein.
• Organelles are functional parts of a cell, examples being mitochondria and lysosomes.
• Cells are the basic units of structure and function, ex. muscle, nerve, or blood cells.
• Tissues are layers or masses of cells with a specific function, ex. adipose tissue.
• Organs are groups of different tissues with a function, examples being the heart, kidney, and stomach.
• Organ systems are groups of organs with a common function, like the digestive system.
• An organism is composed of interacting organ systems, a human for example.

Clinical Applications

• Ultrasound uses high-frequency sound waves to image soft internal structures.
• Ultrasound can be used to obtain sonograms of a fetus in the uterus.
• Magnetic Resonance Scans (MRI) use magnetic fields to change the alignment and spin of certain atoms.
• MRI provides high-resolution images of internal structures like the brain.

Core Themes of Anatomy & Physiology

• Cells constitute all living things.
• The internal environment is the environment within the body.
• Homeostasis keeps the internal environment constant.
• Interdependency of cells requires cells to rely on each other.
• Structure and function are interrelated.
• Cells move from high to low via gradients and permeability, going down pressure and concentration gradients, across permeable membranes.
• Cellular differentiation causes specialization of cells due to gene expression.
• Cell membrane mechanisms determine the entry of substances and respond to signals.
• Cell-to-cell communication happens via membrane receptors.
• Feedback loops are homeostatic mechanisms for stability.
• Balance sustains homeostasis by replacing lost substances and eliminating excesses.
• Energy processes keep cells active.

Characteristics of Life

• Growth occurs via an increase in cell number and size (increase in body size).
• Production of new cells and organisms is reproduction.
• Responsiveness is a reaction to an internal or external change.
• Movement is a change in body position/location or the motion of internal organs.
• Metabolism is the sum of all chemical reactions in a living system in order to produce energy and nutrient cycling.
• Respiration makes energy, typically by taking in oxygen and releasing carbon dioxide.
• Digestion breaks down food for nutrient absorption into the blood.
• Circulation moves chemicals and cells through body fluids.
• Excretion is the removal of waste products.

Requirements of Organisms

• Life requires water, food, oxygen, heat, and pressure from the environment.
• Chemicals:*
  • Water:
    • Is the most abundant substance in the body.
    • Provides an environment for metabolic processes (intracellular & extracellular fluids).
    • Is required for the transport of substances.
    • Aids the regulation of body temperature.
  • Food:
    • Provides necessary nutrients to supply energy.
  • **Oxygen: **
    • Releases energy from food.
  • Heat:
    • Occurs as a form of energy.
    • Helps maintain body temperature.
    • Partly controls the rate of metabolic reactions.
  • Pressure:
    • Is an application of force on an object.
    • Atmospheric pressure is important for breathing.
    • Hydrostatic pressure keeps blood flowing.

Homeostasis

• Homeostasis is the maintenance of a stable internal environment.
  • Homeostatic mechanisms are self-regulating systems that monitor and correct the internal environment.
  • There are three parts to a homeostatic mechanism:
    • The receptor detects and provides information about the stimuli.
    • The control center is the decision-maker that maintains a set point.
    • The effector is the muscle/gland that responds to the control center and causes change in the internal environment.
  • Negative feedback returns conditions toward a normal range when there is a deviation from the set point.
    • Negative feedback prevents sudden, severe changes in the body.
    • It controls body temperature, blood pressure, and glucose level in the blood.
  • Positive feedback intensifies a change/deviation instead of reversing it.
    • Positive Feedback can be short-lived, produces unstable conditions and does not lead to homeostasis.
      • Blood clotting and uterine contractions of childbirth are examples of positive feedback.

Organization of the Human Body

• The human body consists of an axial and appendicular portion.
• The axial portion consists of the head, neck, and trunk.
• The appendicular portion consists of the upper and lower limbs.
• Major cavities inlude: cranial, vertebral, thoracic, and abdominopelvic
  • Cranial cavity houses the brain.
  • Vertebral canal contains the spinal cord.
  • Thoracic cavity houses the lungs and thoracic viscera.
  • Abdominopelvic cavity contains abdominal and pelvic viscera.
• Diaphragm separates the thoracic and abdominopelvic cavities.
  • Mediastinum: area between the lungs in which contains the heart, esophagus, trachea, and thymus gland.
  • Abdomino-pelvic cavity consists of the abdominal cavity and pelvic cavity:
    • Abdominal cavity: extends from the diaphragm to the top of the pelvis and contains the stomach, liver, spleen, kidneys, small intestine, and most of the large intestine.
    • Pelvic cavity: enclosed by the pelvic bones and comprised of the end of the large intestine, urinary bladder, and internal reproductive organs.
• Small cavities found in the head:
  • Oral cavity
  • Nasal cavity
  • Orbital cavities
  • Middle ear cavities
• Thoracic and abdominopelvic cavities are lined with double-layered serous membranes, made up of a slippery fluid that prevents friction between layers.
• Visceral layer covers an organ.
• Parietal layer lines the cavity wall.

Examples of serous membranes

• Visceral and parietal pleura (around lungs in thorax)
• Visceral and parietal pericardium (around heart in thorax)
• Visceral and parietal peritoneum (around abdominopelvic organs)

Organ Systems

• The integumentary system provides body covering and protection, regulates body temperature and sensory reception, and produces Vitamin D.
• The skeletal system supports and provides movement, framework, and protection, in addition to attachment sites, storage of inorganic salts, and production of blood cells.
• The muscular system provides support and movement in addition to being the main source of body heat and posture.
• The nervous system integrates and coordinates organ function via nerve impulses and neurotransmitters for rapid short-term effects.
• The endocrine system integrates and coordinates organ function via hormones for slower, longer-lasting effects.
• The cardiovascular system transports gases, nutrients, blood cells, hormones, and wastes.
• The lymphatic system transports fluids from tissue spaces to blood, carries fats from the digestive system to the blood, and defends the body against infection.
• The digestive system receives and breaks down food, absorbs digestion products, and excretes the wastes.
• The respiratory system moves air in and out of the body for gas exchange (oxygen and carbon dioxide) between blood and air and absorbs oxygen.
• The urinary system removes blood wastes, regulates electrolyte and water balance and blood pressure, produces urine, and excretes it by transporting it outside of the body.
• The reproductive system in male and female systems produces and transports sex cells and hormones to produce new organisms.
• Female systems also provide for fetal development and childbirth.

Lifespan Changes

• Aging occurs from the microscopic to the whole-body level.
• Hair loses pigment, becoming gray or white.
• Skin wrinkles due to a decrease in subcutaneous fat.
• Skin stiffens due to a decrease in collagen and elastin.
• The percentage of fats in tissues increases.
• Joints may develop stiffness.
• Elevated blood pressure may progress to hypertension.
• Elevated blood glucose may progress to type 2 diabetes mellitus.
• Tissues atrophy and organs shrink.
• Cells reach the end of their ability to undergo cell division as the tips of chromosomes are lost.
• Metabolic rate decreases.
• Decreased production of enzymes and other proteins occurs.
• Some develop dementia/Alzheimer’s disease.

Anatomical Terminology

Anatomical Position:

• Standing erect, facing forward, with upper limbs at the sides and palms are facing forward.
• Anatomical terms of relative position are based on a person standing in anatomical position.

Terms of Relative Position:

• Superior (above) and Inferior (below)
• Anterior or ventral (toward the front) and posterior or dorsal (toward the back)
• Medial (toward the midline) and lateral (away from the midline)
• Bilateral (paired structures, on both sides)
• Ipsilateral (on the same side) and contralateral (on the opposite side)
• Proximal (close to the point of attachment to the trunk) and distal (farther from the point of attachment to the trunk)
• Superficial (close to the body surface) and deep (more internal)

Body Sections or Planes:

• Sagittal section: Longitudinal cut dividing body into left and right portions.
• Mid-sagittal/median section: Divides body into equal left and right portions.
• Parasagittal section: Sagittal section lateral to the midline; divides the body into unequal left and right portions.
• Transverse or horizontal section: Divides the body into superior and inferior portions.
• Coronal or frontal section: Longitudinal cut dividing the body into anterior and posterior portions.
• Sections of cylindrical organs
• Cross section: Cut across the structure
• Oblique section: An angular cut
• Longitudinal section: A lengthwise cut

Explore the relationship between anatomy and physiology in medical science's progression. Understand how structural changes affect bodily functions, focusing on advancements from simple observations to scientific approaches to the respiratory and urinary systems and reproductive differences.