C3.1  Integration of Body Systems

Guiding Questions:  
Guiding questions help students view the content of the syllabus through the conceptual lenses of both the themes and the levels of biological organization.

• What are the roles of nerves and hormones in integration of body systems? 
• What are the roles of feedback mechanisms in regulation of body systems?

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​Linking Questions:  
Linking questions strengthen students’ understanding by making connections between topics.  The ideal outcome of the linking questions is networked knowledge.

• What are the consequences of positive feedback in biological systems?
• What are examples of branching (dendritic) and net-like (reticulate) patterns of organization?

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Resources:

• ​Quizlet study set for this topic.  Coming soon!

C3.1.1— System integration.

• Define system integration.
• Explain why system integration is needed to perform the functions of life.​

​C3.1.2— Cells, tissues, organs and body systems as a hierarchy of subsystems that are integrated in a multicellular living organism.

• Define tissue, organ and organ systems. 
• Outline how integration occurs between and among tissues, organs and organ systems. 
• Define emergent property.
• State an example of an emergent property for each level of biological organization within a multicellular organism.

C3.1.3— Integration of organs in animal bodies by hormonal and nervous signaling and by transport of materials and energy.

• State the two primary mechanisms by which animals integrate organ systems. 
• Compare the type of signal, transmission of signal, effector response, speed and duration of response between hormonal and nervous signals. 
• Outline the role of blood in the transport of material and energy between organs.

C3.1.4— The brain as a central information integration organ.

• State the function of the brain.
• List sources of information input to the brain. ​​

​C3.1.5— The spinal cord as an integrating center for unconscious processes.

• List organs of the central nervous system. 
• ​Compare and contrast conscious and unconscious processing.
• State that the spinal cord can only coordinate unconscious processes.​​​

​C3.1.6- Input to the spinal cord and cerebral hemispheres through sensory neurons.

• List types of sensory receptors.
• Outline the function of sensory neurons.

C3.1.7- Output from the cerebral hemispheres to muscles through motor neurons.

• State the location and function of the cerebral hemispheres, primary motor cortex and skeletal muscles. 
• Outline the function of motor neurons.

​C3.1.8- Nerves as bundles of nerve fibers of both sensory and motor neurons.

• Define nerve.
• Describe the structures visible in a nerve transverse cross section. 
• State that nerves can contain either or both sensory and motor neurons.

C3.1.9- Pain reflex arcs as an example of involuntary responses with skeletal muscle as the effector.

• Define reflex and reflex arc.
• Outline the input, processing and output of the pain reflex arc, including the role of receptors, sensory neurons, interneurons, motor neurons and effectors.

​C3.1.10- Role of the cerebellum in coordinating skeletal muscle contraction and balance.

• Identify the cerebellum on a diagram of the human brain.
• State the functions of the cerebellum. 

C3.1.11- Modulation of sleep patterns by melatonin secretion as a part of circadian rhythms.

• Define circadian rhythm.
• State the role of suprachiasmatic nuclei cells in the circadian rhythm. 
• Outline how suprachiasmatic nuclei cells sense and respond to changes in light.
• State that melatonin is secreted by the pineal gland glands in preparation sleep. 
• Outline the mechanism of action of melatonin as a signaling molecule. 
• Outline the effects of melatonin on the body.

​​​C3.1.12- Epinephrine (adrenaline) secretion by the adrenal glands to prepare the body for vigorous activity.

• State that epinephrine is secreted by adrenal glands in preparation for vigorous activity.
• Outline the mechanism of action of epinephrine as a signaling molecule. 
• Outline the effects of epinephrine on the body, including:  skeletal muscles, liver, bronchi and bronchioles, ventilation and heart rate, cardiac output, and vessel dilation.

C3.1.13- Control of the endocrine system by the hypothalamus and pituitary gland.

• Outline the role of the hypothalamus as a link between nervous and endocrine systems.
• List body processes that are monitored by the hypothalamus.
• Draw a diagram to illustrate the structural relationship between the hypothalamus and pituitary.

C3.1.14- Feedback control of heart rate following sensory input from baroreceptors and chemoreceptors.

• State that the myogenic heart rate can be adjusted by neural and endocrine feedback mechanisms. 
• Described the structures and functions of nervous tissue that can regulate heart rate, including the role of the medulla oblongata, sympathetic nerve, vagus nerve, baroreceptors and chemoreceptors. 
• Outline the source and effect of epinephrine on heart rate. 
• Outline factors that will increase heart rate.
• Outline factors that will decrease heart rate.

C3.1.15- Feedback control of ventilation rate following sensory input from chemoreceptors.

• State the effect of exercise on CO2 production.
• Outline the relationship between CO2 production and blood pH.
• Outline the feedback loop that regulates the rate of ventilation, including the role of chemoreceptors, brainstem, diaphragm and intercostal muscles. 
• Explain how and why hyperventilation occurs in response to exercise.​

C3.1.16- Control of peristalsis in the digestive system by the central nervous system and enteric nervous system.

• Outline the role of the central and enteric nervous systems in movement of material into, through and out of the gut.
• List components of the movement of material into, through and out of the gut that are under voluntary and involuntary control. ​

AHL ​​​​C3.1.17- Observations of tropic responses in seedlings.

• Contrast positive and negative tropism. 
• Outline phototropism and gravitropism in roots and stems.​

AHL ​​​​C3.1.18- Positive phototropism as a directional growth response to lateral light in plant shoots.

• Outline the cause and consequence of positive phototropism in a plant shoot.​

AHL ​​​​C3.1.19- Phytohormones as signaling chemicals controlling growth, development and response to stimuli in plants.

• Define phytohormone.
• List examples of chemicals that function as phytohormones.
• Outline role of phytohormones in plant growth, development and response to stimuli. ​

AHL ​​​​C3.1.20- Auxin efflux carriers as an example of maintaining concentration gradients of phytohormones.

• State two roles of the hormone auxin.
• Describe the mechanism of movement of auxin into and between plant cells. ​

AHL ​​​​C3.1.21- Promotion of cell growth by auxin.

• Explain how auxin concentrations allow for phototropism.
• Describe the mechanism of action of auxin in the phototropic response, including the role of H+ ions and cellulose crosslinks. ​

AHL ​​​​C3.1.22- Interactions between auxin and cytokinin as a means of regulating root and shoot growth.

• Outline the source and transport of auxin and cytokinin in plants.
• Explain how root and shoot growth are regulated by the interaction of auxin and cytokinin. ​

AHL ​​​​C3.1.23- Positive feedback in fruit ripening and ethylene production.

• State the function of fruits.
• List changes that occur to a fruit as it ripens.
• Describe the positive feedback mechanism of fruit ripening. 
• Outline why fruit ripening has evolved to be rapid and synchronized.​