Question

About how many neurons make up the nervous system? A. Millions B. Hundreds C. Billions D. The CNS and PNS E. Thousands Adrenaline is the only known neurotransmitter in humans. A. True. It triggers all appropriate body responses as directed by the brain. B. False. There are at least 25, and they all produce different responses but only one response at a time. C. False. There are at least 25 neurotransmitters that do different things but work together to produce body responses. D. True. It is responsible for the "fight or flight" response in all animals, not just humans. E. True. This is the only known one but scientists suspect that there are more they haven't found yet. An action potential in a neuron starts as an electrical signal that travels down the cell. How does it get to the next neuron? As a treatment for brain or spinal cord injuries, patients are often initially chilled to lower their body temperature below normal. What good does this do? A. Your nervous system in general works better at cooler temperatures. B. The rate of blood circulation slows, minimizing oxygen uptake and therefore energy use. C. A cold person's movements are much slower and less likely to cause further injury. D. This slows metabolism and reduces swelling and pressure on the area. E. They stay unconscious so they don't feel as much pain. 5. Attention Deficit Hyperactivity Disorder seems to be increasingly diagnosed in young children. Why is this somewhat controversial? A. Many young children just naturally exhibit a lot of the symptoms of ADHD so it's hard to say when it's a "disease." B. There's no effective way to treat ADHA so diagnosing just stresses the parents and children and magnifies the problem C. ADHD is a complex syndrome, and so far there's no way to effectively diagnose it. D. Many more boys than girls are diagnosed with the disorder. E. It is suspected that drug companies bribe doctors in order to get them to prescribe ritalin.

Answer 1

1.C. billions. about 100 billions neurons are there in human brain.

2. B.False. there are atleast 25,they all produces different responses but only one respond at a time.

3. Action potential in neuron starts as an electrical signal and that travells down along with the neuron,untill it reaches the nerve terminal. the synapse is the axon terminal which acts like a junction between two neurons. Transmission of electrical signals takes place in two different wats as physical zand chemical.As the signal reaches to the synapse a chemical substance released in the form of neurotransmitter. along with the gated channels this neurotransmitter transmits to the dendrits of the another neuron which is binds at the synapse region of the neuron.

4. B.The rate of blood circulation slows, minimizing oxygen uptake and therefore energy use.