Reference no: EM132332494

Please read the two posts below done by my classmates and write two short but instructive responses (add reliable information) to both of them.

Nervous Tissue-cells types & unique properties

The nervous is system one of the complex systems in the human body. The nervous system has tasks to receive information about changes in the human body and external environment. Then, the nervous system transmits messages to the central nervous system. Next, the central nervous system processes the information and responses properly, if it requires. Finally, the central nervous system distributes commands mainly to gland and muscle cells. The central nervous system is containing the brain and spinal cord. The peripheral nervous system is containing the rest of the brain including ganglia and nerves. The ganglion is locating in the nerve and containing a concentration of the cell bodies of peripheral neurons. The nerve has contained a package of nerve fibers or axons enfolded in fibrous connective tissue.

The nervous system is including two types of functional divisions named sensory and motor divisions. Sensory and motor divisions divided into two other division named somatic and visceral. The sensory division has a pathway which transmits different receptors from organs to the central nervous system. The purpose of this type of pathway is to inform the central nervous system about stimulation inside and outside the human's body. The somatic division signals from receptors in the muscles, join, bones, and skin. The visceral sensory division transmits signals from the heart, lungs, stomach, and urinary bladder.

The motor division transmits signals from the central nervous system to the muscle and gland cells. The muscle and gland cells transmit out the body's responses, and effector cells and organs respond to the signals. The somatic motor division transmits signals to the skeletal muscles. The signals produce voluntary muscle contractions and involuntary somatic reflexes. The visceral motor division transmits signals to the cardiac muscle, smooth muscle, and glands. There is no voluntary control over the cardiac muscle, smooth muscle, and glands effector. Thus, visceral motor division or autonomic nervous system functions at an unconscious level.

Visceral reflexes named for the responses of the automatic nervous system and the effector. The autonomic nervous system has two additional divisions including the sympathetic division and the parasympathetic division. The sympathetic division manages to stimulate the body for action by accelerating the heartbeat and increasing respiratory airway. On the other hand, the parasympathetic division manages to have a relaxing effect by slowing the heartbeat. Also, the sympathetic division inhibits digestion, and the parasympathetic division stimulates digestion.

The nervous system transmits signals and communicated by nerve cells. The nervous system has three physiological properties which include excitability, conductivity, and secretion. In excitability, cells respond to environmental changes. In conductivity, neurons respond to stimuli. In secretion, the neurotransmitter secretes when the signal reaches the end of a nerve fiber. There are three functional classes of the nervous system. Sensory neurons are for detection of stimuli such as heat, light, and chemicals. Interneurons are for receiving signals from other neurons. Motor neurons are for sending signals to muscle and gland cells.

Neuroglia cells are a type of cells that protect the neurons and help them function. There are six types of neuroglia. Oligodendrocytes cells speed up signal conduction in the nerve fiber. Ependymal cells produce cerebrospinal fluid to bath the central nervous system and fill the system's internal cavities. Microglia cells do a checkup on the brain tissue and phagocytize dead tissues and foreign matters. Astrocytes cells are a supportive framework for the nervous tissue. Schwann cells help in the regeneration of damaged fibers. Satellite cells regulate the chemical environment of the neurons.

Student Primrose :How does bone Grow and Develop

How does bone Grow and Develop (Interstitial Vs Appositional Growth)

Bones has a wide verity of shapes and sizes. But I'm just going to speak about the long bone and how it grows. "The most important bone for Movement are the long Bones" Saladin Anatomy & Physiology Eighth Edition Authors: Christina. Gan and Heather N. Cushman Published by Mcgraw-Hill Education New York, Ny10121 Copyright 2018. There are many different long bones in our body I'm just going to name a few, Tibia, fibia, ulna, phalanges of the hand and foot and also the Femur. There are four types of bone making cells. The first one I'm going to explain is the Osteogenic Cells they develope from the embryonic mesenchyme, this is the beginning of cell multiplication they also allow the other cell to take their position in the cell membrain. The second is Osteoblasts; Osteoblasts are bone building cells. These cells line up in the periosteum. The Periosteum is on the outer layer of the Diaphysis. Thirdly are the Osteocytes are awsome cells. They're great because they have more than one function they help to keep the bone dense and makes sure that the blood has its share of calcium and phospate ions. osteocytes were also former osteoblasts that got traped in the matrix and became osteocytes, They get trapped in the matrix and become firm as more and more osteoclytes begin to concentrate the areas. Osteocytes live in a cavity call lacunea. The last cell im going to explain is the osteoclasts and they are just bone dissolving cells, The osteoclast increases the cell's surface area to allow the bone to grow. Osteoclast desolve the smaller tissues out of the way so the larger bone will have space to grow. The osteoclasts are also larger in size.

The difference between Interstitial vs Appositional Growth. Interstitial growth just means that the cartilage is growing in length to allow the person to become taller. Appositional growth is when the bone widens and thickens.