Lesson 6: Nervous System
1. Animals have nervous systems that detect external and internal signals, transmit and integrate information, and produce responses.
a. The neuron is the basic structure of the nervous system that reflects function.
A neuron is a collection of nerve cells that transfer information within the body. The structure of the neuron allows for pulses of electrical signals and chemical signals to be passed across a synaptic gap. Neurons consist of a cell body, dendrites, and an axon. The cell body contains most of the organelles, the dendrites receive the signals, and the axon transmits the signals.
b. Action potentials propagate impulses along neurons.
Membrane potential is the difference in electrical charge across a cell’s plasma membrane due to the differential distribution of ions. The Na/K pump works to maintain this potential by using ATP to actively transport Na out of the cell and K into the cell. Doing this makes the outside of the cell have a negative charge while the inside is positive.
c. Transmission of information between neurons occurs across synapses.
The transmission of information typically occurs with the use of chemical messengers called neurotransmitters. There are several different types such as Acetylcholine, Epinephrine, and Dopamine. These neurotransmitters and transmitted by the axon to a different neuron’s dendrites, but before that the neurotransmitters must travel over a synapse; a synapse is just a gap so the neurotransmitters are transmitted electrically.
d. Different regions of the vertebrate brain have different functions.
Each section of the brain is used for a different purpose. The brain is typically divided into 4 parts: the cerebrum, the cerebellum, the limbic system, and the brain stem. The cerebrum has 4 more parts called the lobes of the cerebral cortex; it includes the frontal lobe, the parietal lobe, the occipital lobe, and the temporal lobe. Each of those lobes are also responsible for a different task.
a. The neuron is the basic structure of the nervous system that reflects function.
A neuron is a collection of nerve cells that transfer information within the body. The structure of the neuron allows for pulses of electrical signals and chemical signals to be passed across a synaptic gap. Neurons consist of a cell body, dendrites, and an axon. The cell body contains most of the organelles, the dendrites receive the signals, and the axon transmits the signals.
b. Action potentials propagate impulses along neurons.
Membrane potential is the difference in electrical charge across a cell’s plasma membrane due to the differential distribution of ions. The Na/K pump works to maintain this potential by using ATP to actively transport Na out of the cell and K into the cell. Doing this makes the outside of the cell have a negative charge while the inside is positive.
c. Transmission of information between neurons occurs across synapses.
The transmission of information typically occurs with the use of chemical messengers called neurotransmitters. There are several different types such as Acetylcholine, Epinephrine, and Dopamine. These neurotransmitters and transmitted by the axon to a different neuron’s dendrites, but before that the neurotransmitters must travel over a synapse; a synapse is just a gap so the neurotransmitters are transmitted electrically.
d. Different regions of the vertebrate brain have different functions.
Each section of the brain is used for a different purpose. The brain is typically divided into 4 parts: the cerebrum, the cerebellum, the limbic system, and the brain stem. The cerebrum has 4 more parts called the lobes of the cerebral cortex; it includes the frontal lobe, the parietal lobe, the occipital lobe, and the temporal lobe. Each of those lobes are also responsible for a different task.