A study of biology includes the study of the chemical basis of living organisms, DNA. Other related sciences include microbiology and organic chemistry. The word science comes from a Latin word scientica, which means knowledge, or information. Science is a process of systematically gathering detailed information and gaining exact knowledge.
Hormones drive the endocrine system and without them the body could not function.
Hormones are the communicators of the endocrine system and are responsible for maintaining and controlling cellular activity. Hormones regulate bodily functions and are specific in what responses they elicit. As hormones are released into the bloodstream they can only initiate responses in target cells, which are specifically equipped to respond.
Published: Mon, 5 Dec This paper will provide a variety of definitions regarding paranoid schizophrenia, an overall history of the disease, its causes, symptoms, treatment options, myths and . The first time I experienced what I now understand to be post-traumatic stress disorder, I was in a subway station in New York City, where I live. The endocrine system is a group of glands distributed throughout the human body. This group of glands secretes substances called hormones. These hormones are dumping into the bloodstream (Shier, Butler & Lewis, ). The endocrine system does not have a single anatomic location. It is dispersed.
Each hormone due to its chemical structure is recognized by those target cells with receptors compatible with their structure. Once a hormone is released, the first step is the specific binding of the chemical signal to a hormone receptor, a protein within the target cell or built into the plasma membrane.
The receptor molecule is essential to a hormones function. The meeting of the hormone with the receptor cell initiates responses from the target cell. These responses vary according to target cell and lipid solubility.
Hormones are either lipid-soluble or lipid-insoluble, depending on their biochemical structure. The lipid solubility of the hormone determines the mechanism by which it can affect its target cell.
Lipid-soluble hormones are able to penetrate through the cell membrane and bind to receptors located inside the cell. Such hormones diffuse across the plasma membrane and target those receptor cells found within the cytoplasm. Lipid-soluble hormones target the cytoplasmic receptors which readily diffuse into the nucleus and act on the DNA, inhibiting and stimulating certain proteins.
DNA function is of great influence over the cellular activities of the body and therefore such hormonal-DNA interaction can have effects as long as hours and in some cases days. Two known types of lipid soluble hormones are steroids and thyroid hormones.
Both travel over long courses of time via the bloodstream and both directly effect DNA functions. Those hormones which are lipid-insoluble are unable to penetrate through the plasma membrane and function with their target cells in a much different and complex manner.
Lipid-insoluble hormones must bind with cell-surface receptors which follow a different path involving a second messenger. There are three known and accepted secondary messengers which vary in structure and function, but all three carry out the external signal internally.
After a hormone binds with a receptor molecule it via a transducer protein sends the hormones signal through the membrane.
The protein receptor initiates the formation of a second messenger, whether it be it be cAMP or an inositol phospholipid, which then binds to an internal regulator. Each different type of secondary messenger evokes different responses by those cells they affect. An inositol phospholipid pathway can initiate breakdown of liver glycogen and DNA synthesis in fibroblasts.
These responses, however, are short lived responses; much shorter than those by lipid soluble affected cells. Although the cellular mechanisms of hormones vary according to solubility and first and second messengers, such hormones function in eliciting responses from their target cells.
Hormones more or less function as a stimulant, promoting an action in a target cell which can be magnified in stimulating organs or even systems. Hormone stimulation varies from growth and metabolic functions to ova and sperm production.
There are two ways in which the endocrine system affects the rest of the organism.
The first method of transmission, is called local signaling. This is when regulators are released by a gland or cell into the interstitial fluids and are absorbed by nearby cells.
The second method of transmission is called long distance signaling. Long distance signaling takes place when an endocrine cell or neurosecretory cell releases hormones into the bloodstream.
Once in the bloodstream the hormones travel to the receptor cell. When they reach their destination the receptor cell integrates the signal and reacts to its design. Growth factors affect the development of new cells. There are specific hormones that correspond with the development of specific cells.
For example, epidermal growth factor is required to grow epithelial cells. The rate of growth can also be affected, for example an experiment on fetal mice was done to see if rate of growth of skin would change with an influx of hormones. It was found that by injecting the fetal mice with EGF that skin developed faster.
The hypothalamus and pituitary gland are two parts of the brain that have important roles in integrating the nervous and endocrine system.
The hypothalamus is found in the lower part of the brain in the midbrain where it functions in receiving messages from nerves and integrating that into endocrine gland responses.The Endocrine system is a body control system composed of a group of glands that maintain a stable internal environment, homeostasis, by producing chemical regulatory substances called hormones.
The endocrine system includes the pituitary gland, thyroid gland, parathyroid glands, adrenal gland, pancreas, ovaries, and testis.4/4(6). AP Biology Essay Questions The following is a comprehensive list of essay questions that have been asked on past AP exams.
The questions are organized according to units. Unit 1 (Basic Chemistry and Water) 1.
AP Biology Essay Questions The following is a comprehensive list of essay questions that have been asked on past AP exams. The questions are organized according to units. Unit 1 (Basic Chemistry and Water) 1. The unique properties (characteristics) of water make life possible on Earth. Select three properties of water and: for each property, . Europe. Northern Irish DUP's Foster: PM May Should Ask EU for a Better Deal. The leader of the Northern Irish party which props up Prime Minister Theresa May's government said May should ask the. An endocrinologist specializes in all things relating to our hormones. Conditions affected by hormones range from thyroid problems to diabetes and insomnia. Here, we look at the endocrine system.
The unique properties (characteristics) of water make life possible on Earth. Select three properties of water and: for each property, . The hypothalamus is a small area of the brain that helps to stimulate key functions.
For example, it helps to regulate temperature, weight, emotions, the sleep cycle, and the sex drive.
This. Aeon is a registered charity committed to the spread of knowledge and a cosmopolitan worldview. Our mission is to create a sanctuary online for serious thinking. Published: Mon, 5 Dec This paper will provide a variety of definitions regarding paranoid schizophrenia, an overall history of the disease, its causes, symptoms, treatment options, myths and .
Essay # 1. Habitat and Habits Frogs: Rana tigrina is the most widely distributed species in Northern India. Generally frogs are found in ponds, tanks, pools, ditches, etc.