The nervous system works in collaboration with which system to control many aspects of the body and maintain homeostasis?
The nervous system works in collaboration with the endocrine system to control many aspects of the body and maintain homeostasis.
The endocrine system consists of glands that secrete hormones into the bloodstream.
Hormones are chemical messengers that regulate various functions such as growth, metabolism, reproduction and mood.
The nervous system and the endocrine system communicate with each other through feedback loops to ensure a balance between different physiological processes.
Nervous system works by generating “nerve impulses” (action potential) while the endocrine system acts by releasing “hormones”?
The Central Nervous System consists of the ----.
brain and spinal cord
Peripheral nervous system consists of?
a) Somatic Nervous System
b) Autonomous Nervous System.
The autonomic nervous system consists of?
a) Sympathetic nervous system
b) Parasympathetic nervous system..
The Somatic Nervous System is Voluntary or Involuntary in nature?
Voluntary
The Somatic Nervous System is consists of,
Sensory Neurons (Afferent Neurons). (From receptors to CNS).
Motor Neurons (Efferent Neurons.). (From CNS to Skeletal Muscles).
State functions of the Nervous system?
Sensory Functions.
Integrative Functions:
Motor Function:
The Fundamental unit of the nervous system is?
Neurons
Neuroglial Cells.
Cerebrospinal fluid.
Blood Brain Barrier.
Name typical components of a typical neuron?
Cell body.
Dendrites.
Axon.
Neurotransmitter is present in?
Cell body.
Dendrites.
Axon terminals.
Draw a well labeled diagram of a typical neuron.
A part of the neurotransmitter gets destroyed in synapse by enzymatic action while most is recollected by the neuron, the recollection is called .
neuronal reuptake mechanism.
neuronal uptake mechanism.
Name different types of Neurons.
Multipolar Neuron:
Several dendrites and one axon.
E.g. in the brain and spinal cord.
Bipolar Neuron:
Have one main dendrite and one axon.
E.g. Retina, Inner ear, Olfactory area of brain.
Unipolar Neurons:
Developmental stage, in embryo.
Axon and dendrites fuse to form a single process that divides at a short distance from the cell body.
Name different neuroglial cells.
Astrocytes
Microglial Cells.
Oligodendrocytes.
Ependymal cells.
Schwann Cells.
Satellite Cells
Give functions of Ependymal cells?
Arranged in a single layer, cuboidal or columnar in shape and many are ciliated.
Secretes and helps in circulation of CSF (CerebroSpinal Fluid).
Give functions of Astrocytes.
Forms connection between neurons and blood vessels, imp. Part of BBB (Blood Brain Barrier.)
Star shaped with many processes.
Maintains appropriate environment for the generation of nerve impulses.
Provides nourishment to the neurons.
Take up extra neurotransmitters.
Forms a part of BBB..
What is “Membrane Potential”?
Membrane Potential (Transmembrane Potential, Membrane Voltage) is the difference of voltage between inside the cell membrane and outside the cell membrane.
The resting membrane potential is -70mv.
Name the three phases in which action potential takes place?
Depolarization.
Repolarization
Hyperpolarization.
What is Depolarization?
On a receiving stimulus the Na+ ion channels open causing entry of Na+ ions inside the cell.
As Na+ ions are positively charged the resting membrane potential now starts shifting to “0”.
When membrane potential reaches “-55 mv” it is said that the “Action Potential is generated or threshold is generated”.
Due to higher concentration gradient of Na+ ions the membrane potential reaches upto “+30mv”.
Depolarization means shifting of membrane potential from” -70mv to 0”
What is Repolarization?
As the membrane potential reaches “+30mv” it causes the opening of “K+” ion channels.
The K+ ions start leaving the cell to extracellular fluid ( Concentration of K+ ions is less outside the cell).
The loss of K+ ions causes the membrane potential to come down.
The opening of K+ ion channels is slower at the same time the Na+ ion channels start getting inactivated.
Due to this the membrane potential drops to its resting stage i.e -70mv.
The return of membrane potential to -70 mv is called “Repolarization.”
What is Hyperpolarization?
Due to delay in closing of K+ ion channels the further loss of positivity the membrane potential lowers more to -90mv.
Hyperpolarization means dropping of membrane potential to -90mv.
After closing of K+ ion channels the membrane potential comes back to its resting stage and is now ready to receive new stimulus.
What is a Neurotransmitter?
The chemical released by neurons at terminal ends in response to the generated action potential is called a “neurotransmitter.”
The released neurotransmitter helps transmit the nerve impulse.
Name different types of neurotransmitters.
Amino acids: Glycine
Biogenic Amines. Adrenaline
Neuropeptides.: Angiotensin
Name the neurotransmitters whose action is long lasting.
Neuropeptides.