The Nervous System by Anthony Brown https://padlet.com/abrown3212/cqtnijc1rl9s Anthony Brown Shaunti H. Anthony Lee en-us 2017-03-29 18:45:37 UTC 2026-04-22 02:00:06 UTC hello@padlet.com abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163529484 nerv·ous sys·tem
ˈnərvəs ˌsistəm/
noun
noun: nervous system; plural noun: nervous systems
  1. the network of nerve cells and fibers that transmits nerve impulses between parts of the body.
]]> 2017-03-29 18:58:09 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163529484 The nervous system is the part of an animal's body that coordinates its actions and transmits signals to and from different parts of its body. Nervous tissue first arose in wormlike organisms about 550 to 600 million years ago. In vertebrate species it consists of two main parts, the central nervous system (CNS) and the peripheral nervous system (PNS). abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163529736 2017-03-29 18:58:54 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163529736 Brain abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163530952 an organ  part of  the body with soft nervous tissues in the skull of vertebrates, functioning  for the coordinating center of sensation and intellectual and nervous activity.
synonyms are  cerebrum, cerebral matter, and encephalon
]]> 2017-03-29 19:03:14 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163530952 abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163532054 2017-03-29 19:07:51 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163532054 abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163532942 The CNS contains the brain and spinal cord. The PNS consists mainly of nerves, which are enclosed bundles of the long fibers or axons, that connect the CNS to every other part of the body. Nerves that transmit signals from the brain are called motor or efferent nerves, while those nerves that transmit information from the body to the CNS are called sensory or afferent. ]]> 2017-03-29 19:11:19 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163532942 abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163533743  Most nerves serve both functions and are called mixed nerves. The PNS is divided into a) somatic and b) autonomic nervous system, and c) the enteric nervous system. Somatic nerves mediate voluntary movement. The autonomic nervous system is further subdivided into the sympathetic and the parasympathetic nervous systems. ]]> 2017-03-29 19:14:33 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163533743 abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163534151 The sympathetic nervous system is activated in cases of emergencies to mobilize energy, while the parasympathetic nervous system is activated when organisms are in a relaxed state. The enteric nervous system functions to control the gastro.

]]> 2017-03-29 19:16:14 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163534151 abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163534452 At the cellular level, the nervous system is defined by the presence of a special type of cell, called the neuron, also known as a "nerve cell". Neurons have special structures that allow them to send signals rapidly and precisely to other cells. They send these signals in the form of electrochemical waves traveling along thin fibers called axons, which cause chemicals called neurotransmitters to be released at junctions called synapses]]> 2017-03-29 19:17:29 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163534452 abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163534629 Nervous systems are found in most multicellular animals, but vary greatly in complexity.[1] The only multicellular animals that have no nervous system at all are sponges, placozoans, and mesozoans, which have very simple body plans. The nervous systems of the radially symmetric organisms ctenophores (comb jellies) and cnidarians (which include anemones, hydras, corals and jellyfish) consist of a diffuse nerve net. ]]> 2017-03-29 19:18:21 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163534629 abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163535016 2017-03-29 19:19:39 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163535016 abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163535775 2017-03-29 19:23:10 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163535775 Facts about the human brain The human brain is the largest brain of all vertebrates relative to body size. It weighs about 3.3 lbs. ( ... The brain makes up about 2 percent of a human's body weight. The cerebrum makes up 85 percent of the brain's weight. It contains about 86 billion nerve cells (neurons) — the "gray matter"More items... abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163701147 2017-03-30 13:40:14 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163701147 abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163701548 The most complex entity known resides between your ears.

Here are some of the fascinating facts and figures about the human brain.

1. The typical brain is about 2% of a body’s weight but uses 20% of its total energy and oxygen intake. (2)

2. Your brain is 73% water. It takes only 2% dehydration to affect your attention, memory and other cognitive skills. (3, 4)

3. Ninety minutes of sweating can temporarily shrink the brain as much as one year of aging. (5)

]]> 2017-03-30 13:41:12 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163701548 abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163701949 4. Your brain weighs about 3 pounds. Of that, the dry weight is 60% fat, making your brain the fattiest organ. (6)

5. Twenty-five percent of the body’s cholesterol resides within the brain. Cholesterol is an integral part of every brain cell. Without adequate cholesterol, brain cells die. (7)

6. No one knows for sure, but the latest estimate is that our brains contain roughly 86 billion brain cells. (8)

7. Each neuron connects with, on average, 40,000 synapses. (9)

8. A piece of brain tissue the size of a grain of sand contains 100,000 neurons and 1 billion synapses all communicating with each other. (10)

9. All brain cells are not alike. There are as many as 10,000 specific types of neurons in the brain. (11)

]]> 2017-03-30 13:42:23 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163701949 abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163702443 The brain]]> 2017-03-30 13:43:50 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163702443 The spinal cord abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163807229 The spinal cord is a part of the nervous system the connects the the brain to the rest of the nervous system]]> 2017-03-30 18:55:12 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163807229 abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163808538 t is about 45 cm long in men and 43 cm in women it weighs about 35 grams and is protected by the skeletal system. The sensory receptors go through the joints sending a signal to the brain about body positions]]> 2017-03-30 19:00:58 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163808538 abrown3212 https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163810540 If you dont have your spinal cord then you cant move or do anything at all you would be practically paralized ]]> 2017-03-30 19:09:36 UTC https://padlet.com/abrown3212/cqtnijc1rl9s/wish/163810540