The nervous and endocrine system Flashcards
(16 cards)
What is the Nervous system?
- Specialised cells with the purpose of communicating information using electrical signals.
-Split into the Peripheral nervous system and Central nervous system.
What are the 2 main functions of the nervous system?
- To collect, process and respond to information in the environment
-To coordinate the working of different organs and cells in the body
What is the two divisions of the nervous system?
-Central Nervous system
-Peripheral nervous system
What is the central nervous system and what is it made up of (CNS)?
-Made up of the brain and spinal cord
- responsible for all decisions and commands
Describe the structure of the brain.
-Covered by the cerebral cortex which is 3mm thick
- divided into two hemispheres
Describe the function of the spinal cord.
-Spinal cord is an extension of the brain
-passes messages to and from the brain and connects the brain to PNS
- responsible for reflex actions( pulling hand away from hot plate)
What is the peripheral nervous system and what are its subdivisions (PNS)?
-Transmits messages via neurons to and from the CNS to the rest of the body
-Split into the Autonomic Nervous System and the Somatic Nervous system.
What is the autonomic nervous system(ANS)?
-Governs vital functions in the body: breathing and heart rate, digestion, sexual arousal and stress responses
-Two divisions: parasympathetic and sympathetic
What is the somatic nervous system(SNS)?
-Governs muscle movement and receives information from sensory receptors
What is the parasympathetic state and what is the sympathetic states?
-Parasympathetic = Resting and relaxing
-Sympathetic = Physiologically aroused
How and when does the body switch from the parasympathetic to sympathetic state?
-When a stressor is perceived the hypothalamus(part of the brain) activates the pituitary gland which triggers the sympathetic branch of the ANS which causes the sympathetic state.
What is the physiological state of the Parasympathetic state?
-Decreases heart rate
-Decreases breathing rate
-Constricts pupils
-Stimulates digestion
-Stimulates saliva production
- Rectum relaxes
(Opposite effects for sympathetic state)
What is the endocrine system?
-Information system to carry chemical messengers (hormones) into the bloodstream directly into organs
What are glands?
-Organs in the body that make and secrete hormones
What are Hormones?
-Chemical messengers that are secreted from Glands and circulate through the bloodstream to target organs.
What does the adrenal medulla gland secrete?
- It secretes Adrenaline
-Adrenaline causes physiological changes such as increasing heart rate which can trigger the fight or flight response