Integration of body systems

• What is integration in a biological system?

  The ability of parts to function together
• What are emergent properties?

  Properties arising from interactions of components
• What are the integrated body systems of a cheetah?

  • Cellular: DNA blueprints
  • Tissue: flexible spine
  • Organ: enlarged heart
  • Organ system: breathing and circulatory system
  • Organism: effective predator
• What does the nervous system do?

  Sends electrical messages about the body
• What is the endocrine system?

  Network of glands secreting chemical messengers
• What are the differences between the endocrine and nervous systems?

  • Endocrine: chemical signals, via blood, widespread
  • Nervous: electrical signals, via neurons, specific
  • Endocrine: slower, longer-lasting
  • Nervous: faster, shorter duration
• What substances are found in blood?

  Oxygen, carbon dioxide, hormones, nutrients
• What are the functions of the brain?

  • Controls body functions
  • Receives impulses from sensory receptors
  • Integrates information
  • Sends impulses to effectors
  • Stores information
• What part of the brain is responsible for learning and memory?

  Cerebral cortex or cerebellum
• What does the cerebellum control?

  Balance and muscle coordination
• What is the function of the medulla oblongata?


  Controls unconscious actions like breathing
• What do the hypothalamus and pituitary gland control?

  The endocrine system and thermoregulation
• What are conscious processes?

  • Aware of and under your control
  • Involves decision making and learning
• What are unconscious processes?

  • Occur without conscious awareness
  • Automatic and involuntary
  • Examples: heartbeat and digestion
• What is the pathway of nerve impulses?

  1. Sensory receptors
  2. Sensory neuron
  3. Interneuron
  4. Upper motor neuron in brain
  5. Lower motor neuron to neuromuscular junction
• What are nerves composed of?

  • Bundles of sensory and motor neurons
  • Surrounded by protective sheath
• What are the layers surrounding nerve fibers?

  • Endoneurium: surrounds individual fibers
  • Perineurium: surrounds bundles of fibers
  • Epineurium: surrounds multiple bundles
• What is melatonin and its function?

  Hormone regulating circadian rhythm and sleep
• How does melatonin change throughout the day?

  Increases in evening, decreases in morning
• What suppresses melatonin secretion?

  Blue light
• What is epinephrine?

  Peptide hormone secreted by adrenal gland
• What are the effects of epinephrine?

  • Prepares for intense physical activity
  • Widening of bronchioles
  • Increased ventilation
  • Glycogen converted to glucose
  • Increased heart rate
  • Blood flow redirected
  • Pupil dilation
• How is the endocrine system controlled?

  • Hypothalamus is the control center
  • Works with pituitary gland
  • Secretes releasing factors
  • Produces ADH and oxytocin
• What do baroreceptors respond to?

  Stretch in blood vessel walls
• What do chemoreceptors detect?

  Changes in blood chemistry
• Where are chemoreceptors located?

  • In the aorta
  • In carotid arteries
  • Send signals to medulla oblongata
• What do the sympathetic and parasympathetic systems do?

  • Sympathetic: increases heart rate
  • Parasympathetic: decreases heart rate
• How do baroreceptors and chemoreceptors work together?

  • Detect changes in blood
  • Send signals to cardiovascular center
  • Regulate heart rate via SA node
• What causes an increase in heart rate?

  Decrease in blood pressure, pH, or oxygen
• What decreases blood pH during physical activity?

  Carbonic acid
• How do chemoreceptors monitor blood pH?

  • Located in carotid artery
  • Located in medulla oblongata
  • Send signals to respiratory control center
• What regulates ventilation rate and depth?

  • Respiratory control center in medulla oblongata
  • Sends impulses to intercostal muscles and diaphragm
• What is peristalsis?

  • Waves of contraction and relaxation
  • Controlled by CNS and enteric nervous system
  • Involuntary control of gut muscles
• What is the role of the enteric nervous system?

  • Controls movement of food in digestive system
  • Network of neurons in gastrointestinal wall
• What is tropism in plants?

  Growth in response to a stimulus
• What are phytohormones?

  Hormones regulating plant growth and development
• What is accuracy in measurement?

  Close to the true value
• What is precision in measurement?

  The smallest unit of measurement
• What is positive phototropism?

  • Shoots grow towards light
  • Auxin causes elongation on dark side
• What are the types of phytohormones and their functions?

  1. Auxin: promotes stem and root growth
  2. Gibberellins: promote stem growth, delay leaf fall
  3. Abscisic acid: stress hormone, induces dormancy