The various systems of the human body are discussed in this chapter.
On the AP exam, human physiology comes up a lot.
The heart has a passage of blood through it.
The alveolus is the lung's functional unit.
The brain and spine are part of the central nervous system.
The sensory and motor divisions are part of the PNS.
This is a common subject for multiple-choice questions, and you can study the names, origins, and functions of the various hormones in this chapter.
There is a difference between specific and nonspecific immunity.
There is a tour of the human body.
We don't want to hear organisms, we don't want to have lunch, and we don't want to take bathroom breaks.
Here we go.
You are welcome to the heart.
The human heart is a four-chambered organ.
The heart pumps blood from the left ventricle to the aorta.
The superior and inferior vena cavae carry blood from the body to the heart.
The blood leaves the heart through the right atrium and goes through the right ventricle to the lungs.
The blood has made a complete cycle through the body.
The most oxygenated stage of the blood is just after it leaves the lungs and enters the left side of the heart.
The blood is in its lowest oxygenated stage as it reenters the heart.
The left ventricle is the most muscular part of the heart and has the most pressure on it.
The left ventricle is the part of the heart that pumps blood to the rest of the body.
The left ventricle is designed to work.
The right ventricle is smaller and less muscular because it only pumps blood a short distance to the lungs for gas exchange.
If you look to your right, you will see some of the blood and its components passing us.
Hemoglobin is a major component of iron.
The blood contains mostly water.
Our body is protected by the white blood cells.
We will be talking about the immune system.
During the exchange of blood, there are some things that leak out.
Poor lost souls find their way back into the bloodstream through the lymphatic system.
If your neck swells when you are sick with the flu, it's probably because the white blood cells in your neck are growing.
These hardened arteries become narrower and are a prime risk factor for death by embolism--the breaking off of a piece of tissue that lodges in an arteries, blocking the flow of blood to vital tissues.
We are going to go to the lungs.
It will get loud in these windy tunnels if you stay close.
Air enters the body through the nose and mouth.
We will return to this area later on in the tour when we take the road that food uses to get from the mouth to the stomach.
There are small arms waving at us as we go by.
There is a fork in the road.
The one going to the right lung was increased.
They are a single cell in thickness, surrounded by a dense bed of capillaries, and covered by a thin film of water.
This is the place where the exchange of O2 and CO2 occurs.
The primary functional unit of the lung is the alveoli.
Oxygen enters the alveolus the same way as we did, by dissolving in the water lining of the wall.
In a similar way, 2, which is carried by the blood, primarily in the form of HCO3, passes out of the blood.
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The blood goes to the rest of the body.
The mechanism by which breathing actually occurs should be discussed before we move on to the digestive system.
Inhalation increases the volume of the lung.
As a result, the air pressure in the chest falls below that of the atmosphere.
The contraction of the rib-cage muscles allows for an increase in thoracic volume.
The muscles relax after the air exchange, which causes the diaphragm to move up against the lungs.
This causes the pressure in the lungs to be higher than the atmosphere.
It is time to take a tour of the digestive system.
We are going to take a short cut to the mouth as we exhale.
We sit in the mouth.
The beginning of the digestion of food is here.
Simple sugars like maltose are fully absorbed down in the gut.
The saliva acts as a lubricant to help the food move.
During the tour of the respiratory system, the tongue pushed the food toward the crossroad.
The sphinx is usually closed in order to prevent food from coming back up the sphinx to the mouth.
The food is broken into smaller pieces in the stomach.
Many glands can be seen along the edges of the stomach.
The gastric juice produced by some of these glands helps in digestion and lowers the pH.
The beginning of pepsin.
The pepsin is activated by HCl.
Pepsin will only work in a certain range of pH values.
If it were active all the time, it would digest things that are not supposed to.
mucus helps line the stomach.
mucus helps prevent the wall of the stomach from being eaten.
The small intestine is where most of the absorption and digestion of Big Idea 2.A.3 occur.
The terrain is different in this organ.
The hepatic portal vessel is formed by the merging of veins that are in the small intestine.
Before they are sent to the rest of the body, the newly absorbed vitamins and minerals are first absorbed by the liver.
The 15_Anestis_ch15_p177-199.qxd is the major fat-digesting enzyme.
The breakdown of carbohydrates into simpler sugars is continued by Amylase.
Trypsin and chymotrypsin are used to digest the peptides in our diet.
Trypsin and chymotrypsin both cut bonds by phenyalanine.
trypsinogen and chymotrypsinogen are inactive forms of proteolytic enzymes.
trypsin and chymotrypsin are both activated by trypsinogen.
The large intestine includes the cecum, colon, and rectum.
The primary function of this part of the system is to reabsorb water and electrolytes.
As the waste material moves toward the rectum, it is served as a passageway.
The food travels up the colon, across the colon, down the colon, and into the rectum, where it is kept until it is eliminated.
The wall of the abdomen has the kidneys on it.
Blood can be brought to and from the kidneys.
We pulled the bus up to one of the million kidneys.
The blood that enters via the glomerulus is sent to the various nephrons by the branching of the renal artery into smaller and smaller vessels.
The fluids go down the tubule through the loop of Henle and into the collecting duct.
The various collecting ducts of the kidneys come together into the renal pelvis, which leads to the bladder.
The force of blood pressure causes fluid to move from the capillaries into the nephron.
The following section is for legend.
Several nephrons empty into each duct.
The nephron can control what gets released in the urine with the combination of reabsorption and secretion.
Animals use feedback mechanisms only if their concentration is higher than their capacity.
Diabetes can be seen by the amount of blood in the urine.
There is a loop of Henle that is permeable to H2O.
The loop of Henle is not water.
How much water is lost in urine is determined.
The final concentration of the urine is controlled by the osmotic gradient created in the earlier regions of the nephron.
The concentration of urine is controlled by the body.
In times of excessive fluid, the body excretes a large volume of hypotonic urine to conserve salts.
A constant body temperature is important for living organisms.
The skin plays a role in excretion through sweating.
There are four major thermoregulatory processes.
Let's say that two people are sleeping in the same bed, and one of them is cold all the time.
Person A wouldn't make it through the night if it weren't for this process.
Since person B is warmer than person A, person A pulls the heat from person B's body to hers.
If it weren't for our air conditioners in the summer, we wouldn't be writing this book.
In the winter, the cold wind makes it feel like it's cold outside.
The amount of water in the air increases because of the humidity.
We must mention two more terms before moving on to the nervous system.
Humans are endothermic.
At least a cold day doesn't lower the human body temperature.
Fish, reptiles, and Amphibians are good examples of ecstasy.
Animals have cords.
The sensory and motor division of the PNS can be broken down.
The voluntary contraction of muscles is controlled by the ANS while the voluntary contraction of cardiac muscle is controlled by the SNS.
It is important to look at the mechanics of nerve cell transmissions before diving into the various divisions of the nervous system.
There is a nerve cell outside of the bus.
The cell body, dendrite, and axon are the main parts of a nerve cell.
The internet is the cable internet.
They are located in the central nervous system and are involved in the operation.
Muscular contraction is caused by organs exhibit.
That was a perfect example of a nerve.
The neuron's membranes are full of pumps and gated parts.
The nerve impulse that we just saw was caused by the threshold potential being reached.
The cell has channels that open slowly in response to depolarization.
To see where this impulse is going, we need to move further down this axon.
The neurotransmitters diffuse across the gap, causing a new impulse in the target cell.
Two of the most common neurotransmitters used in the body are using chemical signals.
Substances called cholinesterases are used to clear the neurotransmitters.
Involuntary activities are regulated by the ANS.
It is divided into the sympathetic and parasympathetic divisions.
Slower heart rate, decreased blood pressure, and bronchial muscle constriction are promoted by the parasympathetic response.
The sympathetic response prepares us for fight or flight by increasing heart rate, dilated muscles, and blood pressure.
The brain and spine are part of the central nervous system.
The brain has different parts that control different parts of the body.
The hypothalamus and thalamus are contained in the diencephalon.
Review the knowledge you need to score high hunger-meter of the body.
A quick demonstration of muscle contraction will be included in our tour of the muscle types of the body.
When you lift a book and do other voluntary activities, you have a muscle type that works.
Skeletal muscles have multiple nuclei.
The voluntary muscle is controlled by the ANS.
There is a nucleus in smooth muscle cells.
Found in the walls of arteries and other body parts.
Smooth muscles are not striated.
There is a nucleus in cardiac muscle cells.
Cardiac muscle cells are striated.
The action potentials and ion channels are how muscle cells are activated.
We are going to be shown a demonstration of muscle contraction.
Skeletal muscle is composed of myofibrils.
It takes two to tango, and myosin and actin are up to the task.
Myosin is the partner of this dynamic duo.
The myosin molecule's heads are the contact point with the actin.
The head can be either low or high energy.
A relaxed muscle begins with the myosin heads.
The myosin is ready to dance if the myosin is converted into a higher-energy form.
Myosin approaches actin in a smooth manner.
Actin-myosin interaction involves relaxed muscle and contracted muscle.
The two ways when myosin comes back to where we started.
Good essay material can be found on the AP Biology exam.
If our muscles were contracting all the time, it would be really awkward.
It makes sense that there is a way to control the contraction.
The removal of tropomyosin is dependent on the presence of calcium ion.
Calcium causes these two to move away from the actin-myosin binding site.
This allows the actin-myosin dance to happen.
The dance is complete when the calcium is gone.
The neuromuscular junction was mentioned a long time ago.
The release of acetylcholine is caused by nervous impulses from motor neurons.
troponin is found by calcium and let the dance begin.
A variety of cells are distributed by the circulatory system.
We are at the cellular and pituitary.
It is the size of a pea and is divided into two parts, the anterior and the posterior.
The adeno expression is what the anterior pituitary is called.
The way hormones are delivered by the two lobes of the pituitary is different.
If you look closely, you'll see that there's a short stalk that connects the part of the brain that's in the middle of the body to the part that's in the right side of the body.
The hypothalamus is connected to the pituitary through the bloodstream.
When the concentration of a particular anterior pituitary hormone is too low in the circulation, the bloodstream will send releasing factors via the hypothalamus that stimulates the production of the needed hormone.
The brain tissue that makes up the brain is called neural tissue.
The connection to the hypothalamus is neural.
The axons that are sent down the axons to be stored in the posterior pituitary are produced by the nerve cell bodies that are located in the hypothalamus.
The hormones are released when stimulated by the hypothalamus.
Follicle-stimulating hormone is a hormone.
It stimulates the production of sperm in males.
The hormone leptin.
A gonadotropin--stimulates ovulation, formation of corpus luteum, and synthesis of estrogens and progesterone in females.
It stimulates the production of testosterone in males.
The hormone stimulates the Thyroid-stimulating Hormone.
The metabolism of the body is regulated by the rate of metabolism in the body.
Contributes to the growth of the body.
It helps to cope with chronic stress by increasing the production of adrenal cortical hormones.
Decreases the synthesis and release of GnRH.
The reabsorption of water is stimulated by the collecting ducts of the kidneys.
The stress hormone is released.
Increases the blood sugar level in response to stress.
Regulates blood volume by controlling the excretion of sodium.
Big Idea 3.D.1 hormone raises blood sugar level and increases metabolism.
Secreted in response to high blood sugar levels.
Lowers blood sugar.
Secreted in the uterus.
The surge of the menstrual cycle is caused by the release of LH.
It helps maintain the endometrium.
There was a secret in the testes.
Calcitonin lowers blood calcium.
It is released at night.
Negative feedback and positive feedback are the main types of regulation.
A good example of negative feedback is the production of insulin.
When the bloodglucose gets too high, the pancreas is stimulated to produceinsulin, which causes cells to use moreglucose As a result of this activity, the blood sugar level goes down.
There is a feedback mechanism that can be seen in the LH surge.
Estrogen is released as a result of the action of FSH, and travels to the anterior pituitary to cause the release of LH, which stimulates the production of estrogen on the ovaries.
Balance is maintained through homeostasis.
This causes the release of glucagon from the pancreas.
Glucagon stimulates the removal of glycogen from the body and pumps it into the bloodstream.
The release of glucagon stops when the glucose level is back to normal.
The back-and-forth dance helps keep the concentration in our bodies stable over time.
Big Idea 2.C.1 is used to maintain the body's desired blood calcium level.
Animals use feed works to increase the amount of Ca2+ in circulation in three different ways.
Before we move on, we want to make a distinction between the two hormones.
The complexes affect the transcription in the nucleus of cells.
It is going to be an absolute treat.
We will explain some immune system terms to you while we are in transit.
The immune system has two levels of defense.
Organisms are the nonspecific prevention of the entrance of invaders into the body.
The skin covering the entire body is a nonspecific defense mechanism.
The mucus lining of our lungs and trachea helps in the expulsion ofbacteria by keeping them out of cells with a cough.
It is also a dangerous place forbacteria.
A lot of potential invaders can be wiped out by the acidity of the stomach.
Organisms clear away.
The molecule to be cleared must have a sort environment.
Contributes to the growth of these cells.
Cells involved in mechanisms that need clean up assistance, such as platelets, have the ability to produce chemicals that attract macrophages and neutrophils to places such as infection sites to help in the elimination of foreignbacteria.
They are not looking for specific garbage.
Inflammation is a prime example of a nonspecific cellular response.
As you grab a piece of wood, let's say you pick up a tiny splinter.
Animals have mast cells.
Mast cells are damaged by the entrance of the splinter, which causes them to get infections that cause the release of histamine into the bloodstream.
The splinter causes the release of signals that call in our nonspecific phagocytic cell friends, which come to the site of the injury to clear away any debris or pathogens.
The increase in blood flow to the area that occurs in this process causes redness and warmth.
Defense mechanisms are specific to the immune system.
B cells and T cells are the main flavors of lymphocytes.
B cells and T cells mature in the bone marrow.
B cells can differentiate into different types of cells, and there are two main types of T cells.
The main players in cell-mediated immunity are toxic T cells.
After binding, they produce a bunch of T cells that pump out other cells through ical signals, which bring in the B cells to respond.
We arrived at the vaccination site in the left arm, and things are heating up here.
Every B cell has a specific site on its surface.
B cells patrol the body.
The factories that produce 15_Anestis_ch15_p177-199.qxd are the plasma cells.
When released, they bind to the antigens and mark them for the macrophages to destroy.