unit 5 bio

• What is homeostasis?

  It's maintaining a stable internal environment
• Why do cells need specific conditions to function?

  To operate properly without stress
• What are some conditions that cells cannot tolerate?

  Extreme temperatures and pH levels
• What does our body regulate to maintain homeostasis?

  Temperature, glucose, and water levels
• How do temperature and glucose levels fluctuate?

  They fluctuate within small bounds
• What is the definition of homeostasis?

  Regulation of internal conditions for stability
• How does the body maintain internal conditions despite external changes?

  By regulating itself through automatic control systems
• What is the normal body temperature humans maintain?

  37 degrees Celsius
• What are the three main components of automatic control systems?

  Receptors, coordination centers, and effectors
• What do receptors do in the control system?

  Detect changes in conditions
• What role do coordination centers play?

  Interpret changes and decide actions
• What are effectors in the control system?

  Muscles or glands that carry out changes
• How do the nervous and endocrine systems communicate?

  Through electrical impulses and hormones
• How does the nervous system send signals?

  Through fast electrical impulses
• What is the main characteristic of the endocrine system?

  It uses hormones released into the bloodstream
• How does the speed of the endocrine system compare to the nervous system?

  It is slower and longer lasting
• What is the mechanism called that regulates homeostasis?

  Negative feedback
• What happens when glucose levels rise too high?

  Negative feedback decreases glucose levels
• What occurs if glucose levels drop too low?

  Negative feedback increases glucose levels
• How does the body respond to a cold environment?

  By shivering to increase body temperature
• What happens when the body temperature rises too high?

  Receptors detect the change and signal effectors
• What is the overall process of homeostasis?

  Maintaining a stable internal environment
• What are the steps involved in the negative feedback mechanism for temperature regulation?

  1. Receptors detect temperature change
  2. Coordination centers interpret the change
  3. Effectors carry out responses (e.g., shivering or sweating)
  4. Body temperature returns to normal
• How do the nervous and endocrine systems differ in their functions?

  • Nervous System:
  • Sends fast electrical impulses
  • Immediate response to stimuli
  • Endocrine System:
  • Releases hormones into the bloodstream
  • Slower, longer-lasting effects
• What organ systems do humans rely on for communication between body parts?

  Nervous system and endocrine system
• What is the main function of the nervous system?

  To coordinate behavior and respond to surroundings
• What are the key components of the nervous system to know?

  • Structure of a nerve cell
  • Structure of the whole nervous system
  • How a reflex arc works
• What is another name for a nerve cell?

  Neuron
• How are neurons adapted to carry electrical impulses?

  They are long, thin, and have branch connections
• What is the role of a synapse in neuron communication?

  It connects two nerve cells for impulse transfer
• What happens when an electrical impulse reaches the end of a nerve?

  Chemicals are released to trigger another impulse
• How does the structure of the nervous system relate to its function?

  Its structure allows rapid communication and coordination
• What makes up the central nervous system (CNS)?

  Brain and spinal cord
• What is the role of sensory neurons in the CNS?

  They carry information from receptors to the CNS
• What type of information do sensory neurons transmit?

  Information about changes in the body
• What do motor neurons do in the nervous system?

  They send impulses from the CNS to effectors
• What are effectors generally in the nervous system?

  Muscles or glands
• What is a reflex arc?

  • Nerve pathway for unconscious reflexes
  • Example: moving hand from a hot surface
  • Rapid and automatic response to stimuli
• What is the benefit of reflexes in the nervous system?

  They allow rapid and automatic responses
• What is the role of receptor cells in a reflex action?

  They detect stimuli and initiate impulses