6.3 Nervous control Flashcards
What is the cerebrum?
Cerebrum – occupies more than 80% of the brain and contains over 10 billion neurons. The cerebrum controls your conscious thoughts and the intentional (voluntary) movement of everybody’s part. It also receives sensory messages from all body parts.
What are the two parts of a cerebrum?
The cerebrum is made up of two parts called the right and left cerebral hemisphere. The right cerebral hemisphere controls the left side of your body and the left cerebral hemisphere controls the right side of your body. Each side of the brain dominates in a particular task like one side has more logical thinking and the other side can be more creative. Your cerebellum is responsible for coordination and balance.
What is the brain stem?
Brain stem – the lower part of the brain stem or medulla can be seen where the spinal cord widens just after it passes the skull. It controls the body’s vital functions such as breathing, blood pressure, and heart rate.
What is the somatic nervous system?
Somatic nervous system – collects this information through receptors in sensory organs such as the eyes and ears. The somatic nervous system also coordinates movement of the body. It detects changes in the environment, the changes stimulate the nerve endings to send messages to your brain.
What is a stimulus?
Stimulus – something that you can detect using your sense organs is a stimulus. Stimuli in your environment includes temperature, light, touch, smell and sound.
In your body what are the 5 different types of receptors? (Mechanoreceptors, photoreceptors, thermoreceptors, chemoreceptors, sensitive skin)
Mechanoreceptors - are sensitive to stimuli such as touch, and also make your aware of your muscles being stretched
Photoreceptors – on the eye are sensitive to light.
Thermoreceptors – respond to change in temperature
Chemoreceptors - are sensitive to chemicals such as those found in you ( taste)
Sensitive skin – responds to many different sensations such as touch, pain, and temperature.
What is the autonomic nervous system and what are its two main parts? (Sympathetic and parasympathetic)
Autonomic nervous system – control activities like your heart beat, or food moving through your small intestine, activities that you don’t realize you do. The autonomic nervous system has two parts:
* Sympathetic nervous system – speeds up the functions of the body and makes it work more effectively. It is the system that prepares your body for emergencies by making you more alert and ready to act.
* Parasympathetic – slows everything down, it is the system in control when you are resting.
Functions of the sympathetic and parasympathetic nervous systems are … dont need to answer
The sympathetic nervous system:
* diverts blood flow away from the digestive tract and the skin
* stops peristalsis-the muscular action that mixes food in the intestines
* maintains blood flow to the lungs and the muscles of the skeleton-blood flow to the muscles may be increased by up to 120%
* opens the bronchioles (airways to the lungs)-this increases the amount of air able to enter the lungs,
* increasing the supply of oxygen to the body
* increases heart rate, thereby increasing blood flow to the muscles of the skeleton
* relaxes the muscles in the eye and dilates the pupils, allowing more light to enter the eye and improving distance vision
* increases blood flow to the heart.
The functioning of the parasympathetic nervous system:
* increases blood flow to the digestive tract stimulates the salivary glands and increases the rate of peristalsis, in support of digestion
* reduces the diameter of the bronchioles when there is a reduced need for oxygen
* controls the heartbeat
* contracts the muscles of the eye and reduces the diameter of the pupil to allow close vision.
