Mindblown: a blog about philosophy.
-
Chemical Nature of Hormones
Chemically, hormones may be classified as either proteins or steroids. All of the hormones in the human body, except the sex hormones and those from the adrenal cortex, are proteins or protein derivatives.
-
Endocrine Glands
The endocrine glands do not have ducts to carry their product to a surface. They are called ductless glands. The word endocrine is derived from the Greek terms “endo,” meaning within, and “krine,” meaning to separate or secrete. The secretory products of endocrine glands are called hormones and are secreted directly into the blood and then carried…
-
Exocrine Glands
Exocrine glands have ducts that carry their secretory product to a surface. These glands include the sweat, sebaceous, and mammary glands and, the glands that secrete digestive enzymes.
-
Introduction to the Endocrine System
The endocrine system, along with the nervous system, functions in the regulation of body activities. The nervous system acts through electrical impulses and neurotransmitters to cause muscle contraction and glandular secretion. The effect is of short duration, measured in seconds, and localized. The endocrine system acts through chemical messengers called hormones that influence growth, development, and metabolic activities. The action of the endocrine…
-
Review
Here is what we have learned from this Introduction to the Nervous System: The nervous system is the major controlling, regulatory, and communicating system in the body. It is the center of all mental activity including thought, learning, and memory. The various activities of the nervous system can be grouped together as three general, overlapping functions:…
-
Autonomic Nervous System
The autonomic nervous system is a visceral efferent system, which means it sends motor impulses to the visceral organs. It functions automatically and continuously, without conscious effort, to innervate smooth muscle, cardiac muscle, and glands. It is concerned with heart rate, breathing rate, blood pressure, body temperature, and other visceral activities that work together to maintain homeostasis. The autonomic nervous system…
-
Spinal Nerves
Thirty-one pairs of spinal nerves emerge laterally from the spinal cord. Each pair of nerves corresponds to a segment of the cord and they are named accordingly. This means there are 8 cervical nerves, 12 thoracic nerves, 5 lumbar nerves, 5 sacral nerves, and 1 coccygeal nerve. Each spinal nerve is connected to the spinal cord by a dorsal root and…
-
Cranial Nerves
Twelve pairs of cranial nerves emerge from the inferior surface of the brain. All of these nerves, except the vagus nerve, pass through foramina of the skull to innervate structures in the head, neck, and facial region. The cranial nerves are designated both by name and by Roman numerals, according to the order in which they appear on the inferior surface of the brain. Most of…
-
Structure of a Nerve
A nerve contains bundles of nerve fibers, either axons or dendrites, surrounded by connective tissue. Sensory nerves contain only afferent fibers, long dendrites of sensory neurons. Motor nerves have only efferent fibers, long axons of motor neurons. Mixed nerves contain both types of fibers. A connective tissue sheath called the epineurium surrounds each nerve. Each bundle of nerve fibers is…
-
Brain Tumor
Glioma refers to tumors that arise from the support cells of the brain. These cells are called glial cells. These tumors include the astrocytomas, ependymomas and oligodendrogliomas. These tumors are the most common primary brain tumors.
Got any book recommendations?