What Are the Major Physiological Systems ? Nervous system – relays messages through nerve impulses Nervous system – relays messages through nerve impulses Responsible for controlling and integrating the other systems of the body Neurons are the basic units Endocrine system – glands which secrete chemical messages (hormones) Endocrine system – glands which secrete chemical messages (hormones)
What Are the Major Parts of a Neuron ? Dendrites – receive information Dendrites – receive information Cell body – generates electrical signals or action potentials Cell body – generates electrical signals or action potentials action potentials action potentials Axon – transmits signals at the synapse by way of neurotransmitters Axon – transmits signals at the synapse by way of neurotransmitterssignalssynapseneurotransmitterssignalssynapseneurotransmitters
Neuron
Action Potential Movie
What Are the Major Divisions of the Nervous System ? Central nervous system (CNS) Central nervous system (CNS) Brain and spinal cord Peripheral nervous system (PNS) Peripheral nervous system (PNS) Sensory and motor neurons that connect the CNS to the rest of the body
CNS & PNS
What Are Some of the Major Features of the Brain’s Structure ? The brain consists of 3 major parts The brain consists of 3 major parts Hindbrain – brainstem Midbrain – limbic system Forebrain – cerebral cortex
Hindbrain Graphic
Midbrain Graphic
Forebrain Graphic
What Are Some of the Major Features of the Brain’s Structure ? The brain is divided into a left hemisphere and a right hemisphere The brain is divided into a left hemisphere and a right hemisphereleft hemisphereright hemisphereleft hemisphereright hemisphere
Left hemisphere movie
What Are Some of the Major Features of the Brain’s Structure ? The corpus callosum connects the hemispheres The corpus callosum connects the hemispheres
Split Brain Movie
What Are the Major Divisions of the Peripheral Nervous System ? Somatic nervous system – connects CNS with the skeletal muscles & senses Somatic nervous system – connects CNS with the skeletal muscles & senses Autonomic nervous system – connects CNS with the internal organs and glands Autonomic nervous system – connects CNS with the internal organs and glands Sympathetic division – produces the emergency reaction Parasympathetic division – returns body to normal functioning
Endocrine System
What Are the Major Divisions of the Endocrine System ? Pituitary gland – the most influential gland Pituitary gland – the most influential gland Influenced by the hypothalamus Regulates growth Controls other glands Located on the underside of the brain
What Are the Major Divisions of the Endocrine System ? Thyroid gland – located below the larynx Thyroid gland – located below the larynx Produces thyroxin Regulates body’s metabolism Parathyroid glands – 4 pea-shaped organs in the thyroid gland Parathyroid glands – 4 pea-shaped organs in the thyroid gland Regulates calcium in blood Related to excitability of nervous system
What Are the Major Divisions of the Endocrine System ? Pancreas – located in stomach area Pancreas – located in stomach area Regulates level of sugar in blood by secreting insulin Gonads – ovaries & testes Gonads – ovaries & testes Produces secondary sex characteristics Adrenal glands – located above kidneys Adrenal glands – located above kidneys Helps with fight/flight/fright reaction