LMS

Animals have to respond quickly to the diverse environmental changes in a fraction of time therefore, they need a more efficient coordination system

Neurons are cells within the nervous system that transmit information to other nerve cells, muscle, or gland cells and are responsible for nervous coordination.

Since, photoreceptors are associated with the detection of stimulus of light, which are electromagnetic in nature; hence, these receptors are also called as electromagnetic receptors

In the skin, there are at least 3 types of sensory endings involved in touch stimulus sensation. In skin, the receptors are concerned with at least five different senses; touch, pressure, heat, cold, and pain

Stretch receptors are mechanoreceptors responsive to distention of various organs and muscles, and are neurologically linked to the medulla in the brain stem via afferent nerve fibers. Examples include stretch receptors in the heart, blood vessels, in the colon wall, and in the lungs

At rest state, Na ions are 10 times high in concentration outside the neuron while K ions are 20 times high inside the neuron. During this state, small amount of K ions leaks outside though plasma membrane via K ion channels.

Sensory neurons connect CNS with receptors and motor neurons connect CNS with effectors.

Neurons are classified as unipolar, bipolar and multipolar on the basis of dendrites that originate from the cell body.

The central part of neuron which give rise to cytoplasmic processes and contain nucleus and other organelles embedded in cytoplasmic matrix is called soma

Nucleus and organelles are present in the central part of neuron

Receptors give input to CNS by sensory neurons whereas output is provided to the effectors by motor neurons.

Receptors, which are located far away from CNS, are innervated by sensory neurons.

Reflex arc is the pathway of passage of impulse during reflex action:

Threshold stimulus is responsible for the opening of Na-gates. As a result, Na ions rush in to the neuron due to concentration gradient difference.

Nerve impulse is a series of electrochemical changes which run throughout the length of neuron.

Inside of neuron is more negatively charged due to the presence of proteins and large organic ions. Moreover, passive leakage of potassium ions also contributes in negativity of neurilemma.

Serotonin and dopamine are mainly used for CNS synapses

Acetylcholine is use to transmit impulse from neuron to muscle fiber at neuromuscular junction.

Adrenaline, nor-adrenaline, serotonin and dopamine are mainly used within CNS synapses.

Gray matter of brain lies outside while in spinal cord it is present inside and CSF runs inside the canal.

Dorsal root ganglion consists of cell bodies of sensory neurons.

Peripheral nervous system consists of sensory and motor divisions

All spinal nerves have fibers of both sensory and motor neurons

ANS mainly controls involuntary actions.

The fibers of sympathetic nervous system originate from the bottom portion of spinal cord and they terminate in nearby ganglia.

Sympathetic nervous system initiates such responses which help in fight and flight responses.

Vagus nerve is the part of parasympathetic division of ANS.

Hormones are chemical messengers and are produced by specialized endocrine glands or cells. After release, they are delivered to their target sites by transport system

Amino acid derivatives are produced by endocrine glands which are located above kidneys and in neck region.

Hormones are chemically peptides, proteins, steroids or amino acid derivatives in nature.

Hypothalamus contains neurosecretory cells and controls the secretions of pituitary gland.

Hormones produced from neurosecretory cells of hypothalamus are called as neurosecretions.

ADH released from posterior pituitary and target the collecting ducts in nephrons. There, it regulates the reabsorption of water which, as a result, normalize the blood volume and blood pressure.

Anterior lobe of pituitary produces hormones which act on other endocrine glands i.e. TSH, ACTH. It also produces hormones which directly regulate the functioning of cells i.e. prolactin.

Anterior pituitary is referred as master gland because its secretions are responsible for regulating other endocrine glands of body.

Anterior pituitary produces growth hormone in response to hypothalamic releasing factor

Such hormones which acts on other endocrine glands and regulate their secretions are called as tropic hormones.

Graves’ disease is an autoimmune disorder in which abnormal antibodies continuously stimulate the thyroid gland.

The other name of thyroxine is tetraiodo-thyronine.

Deficiency of thyroxine in early life causes cretinism. Its symptoms include low BMR, poor growth and development, coarse scanty hairs, mental retardation and scaly skin

Secretion of TSH is regulated through negative feedback mechanism by monitoring blood thyroxine levels.

Parathyroid gland produces parathormone which is released in response to low blood calcium levels and it regulate calcium from bones to the blood. Its deficiency leads to hypocalcemia.

Malfunctioning β- cells will not produce enough insulin in response to the blood glucose being absorbed from the digestive tract. As a result, blood glucose level will received.

Insulin lowers blood glucose level by:-          Increase peripheral uptake and utilization of glucose-          Increase the conversion of glucose into glycogen-          Decrease glycogenolysis-          Increase the conversion of glucose into protein and fats 

Insulin lowers blood glucose level by:-          Increase peripheral uptake and utilization of glucose-          Increase the conversion of glucose into glycogen-          Decrease glycogenolysis-          Increase the conversion of glucose into protein and fats 

Insulin lowers blood glucose level by:-          Increase peripheral uptake and utilization of glucose-          Increase the conversion of glucose into glycogen-          Decrease glycogenolysis-          Increase the conversion of glucose into protein and fats 

ACTH is a tropic hormone and it regulates the production and secretions of corticosteroids from adrenal cortex.

Cortisol is a corticosteroid and is regulated by tropic factor from pituitary.

The hormones which control the secondary sexual characters in males and females are testosterone and estrogen, respectively.

Sex hormones in male and female are important for gametogenesis and sexual maturity