Nervous System

• What are neurons?


  Nerve cells - 100 billion neurons in the nervous system
• What percentage of neurons are found in the brain? 


  About 80%
• How do neurons help the nervous system?


  Help the nervous system communicate via transmitted signals
• How are signals transmitted?


  electrically and chemically
• What 2 categories is the human nervous system split into?

  • Central nervous system (CNS)
  • Peripheral nervous system (PNS)
• What are the 2 sub-categories of the PNS?


  • Somatic Nervous System
  • Autonomic Nervous System
• What are the 2 sub-categories of the CNS?


  • Brain
  • Spinal Cord
• What are the 2 sub-categories of the ANS?


  • Sympathetic state
  • Parasympathetic state
• What is the definition of the human nervous system?


  The human nervous system is the primary communication system that uses specialised cells (neurons) to pass and receive messages across the body electrically and chemically
• What are the 2 main functions of the nervous system?


  • Collect, process and respond to information in the environment
  • Co-ordinate the working of different organs and cells in the body
• What is the spinal cord and what does it do?


  • It is an extension of the brain
  • It is responsible for reflexes
• What are the key facts about the brain?

  • Made up of 2 hemispheres
  • It is the centre of conscious awareness
  • The cerebral cortex (brain's outer layer) is especially developed in humans
• What does the PNS do?


  The peripheral nervous system transmits messages via millions of neurons to and from the CNS
• What does the ANS do?


  The autonomic nervous system governs vital functions in the body, e.g. breathing, heart rate, digestion, sexual arousal, and stress responses
• What does the SNS do?


  The somatic nervous system controls muscle movements and receives information from the sensory receptors
• What does the endocrine system do and how does it do this?

  The endocrine system works alongside the nervous system for vital functions using the sympathetic and parasympathetic systems. Chemical signals are sent (slow-moving and longer-lasting) via hormones and glands
• What are glands and hormones?

  Glands produce hormones.

  Hormones are chemical messengers that tell the body to perform specific physical and mental functions via the bloodstream
• What do hormones affect?

  Most affect cells in several organs
• What do hormones not cause?

  Hormones do not cause behaviour
• What do hormones do/cause?


  Alter the probability of certain behaviours occurring (influence behaviour)
• What is the pituitary gland and its function?


  The pituitary gland is the master gland and controls the release of hormones