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Generally as little as 30 minutes of noncontinuous exercise over the course of each day has beneficial effects and has been shown to lower the rate of heart attack by nearly 50 percent. While it is always advisable to follow a healthy diet, stop smoking, and lose weight, studies have clearly shown that fit, overweight people may actually be healthier overall than sedentary slender people. Thus, the benefits of moderate exercise are undeniable.

Clinical considerations in vascular homeostasis

Any disorder that affects blood volume, vascular tone, or any other aspect of vascular functioning is likely to affect vascular homeostasis as well. That includes hypertension, hemorrhage, and shock.

Hypertension and hypotension

Chronically elevated blood pressure is known clinically as hypertension    . It is defined as chronic and persistent blood pressure measurements of 140/90 mm Hg or above. Pressures between 120/80 and 140/90 mm Hg are defined as prehypertension. About 68 million Americans currently suffer from hypertension. Unfortunately, hypertension is typically a silent disorder; therefore, hypertensive patients may fail to recognize the seriousness of their condition and fail to follow their treatment plan. The result is often a heart attack or stroke. Hypertension may also lead to an aneurism (ballooning of a blood vessel caused by a weakening of the wall), peripheral arterial disease (obstruction of vessels in peripheral regions of the body), chronic kidney disease, or heart failure.

Listen to this CDC podcast to learn about hypertension, often described as a “silent killer.” What steps can you take to reduce your risk of a heart attack or stroke?

Hemorrhage

Minor blood loss is managed by hemostasis and repair. Hemorrhage is a loss of blood that cannot be controlled by hemostatic mechanisms. Initially, the body responds to hemorrhage by initiating mechanisms aimed at increasing blood pressure and maintaining blood flow. Ultimately, however, blood volume will need to be restored, either through physiological processes or through medical intervention.

In response to blood loss, stimuli from the baroreceptors trigger the cardiovascular centers to stimulate sympathetic responses to increase cardiac output and vasoconstriction. This typically prompts the heart rate to increase to about 180–200 contractions per minute, restoring cardiac output to normal levels. Vasoconstriction of the arterioles increases vascular resistance, whereas constriction of the veins increases venous return to the heart. Both of these steps will help increase blood pressure. Sympathetic stimulation also triggers the release of epinephrine and norepinephrine, which enhance both cardiac output and vasoconstriction. If blood loss were less than 20 percent of total blood volume, these responses together would usually return blood pressure to normal and redirect the remaining blood to the tissues.

Additional endocrine involvement is necessary, however, to restore the lost blood volume. The angiotensin-renin-aldosterone mechanism stimulates the thirst center in the hypothalamus, which increases fluid consumption to help restore the lost blood. More importantly, it increases renal reabsorption of sodium and water, reducing water loss in urine output. The kidneys also increase the production of EPO, stimulating the formation of erythrocytes that not only deliver oxygen to the tissues but also increase overall blood volume. [link] summarizes the responses to loss of blood volume.

Questions & Answers

define cell injuries
Siva Reply
it is defined as any damage to structural and functional behaviour of cell...and is not performing appropriately.
ram
what is the proximity of uterus or womb and kidney
Gebregiorgis Reply
answer is needed
Hirsi
hirsi dahir
Moha
war hye
Moha
i dont know
Erika
im just new in here.
Erika
im a freshmen student
Erika
ok Erik welcome
Moha
hy
Amina
Am Amina
Amina
?
Kshitiz
say ?
Kshitiz
proximity of womb that is uterus is urinary bladder..bowel loop(means intestinal loop)..and rectum and that if kidney is..stomach,ureter,spleen in left, duodenum,quadratus lumborum muscle,psoas muscle,ribs(6,7,8),suprarenal gland,jejunum,colic flexure on right,.
ram
hey hlo...m new here..yogesh Jindal🤗🤗guys listen proximity is same the structure lying on it's surfaces..or around it...so all must reply...as each new nd all must know structure around organs...nd vessels too
ram
okz thanks bro me too new .....u all are unknow for me🤔🤔🤔🤔🤔
Kshitiz
of course m unknown to all
ram
Maine to ye names hi first tym sune hai
ram
can i ask a question kn you guys?
Erika
yes Erik came on we here to answer any questions posted
Moha
give me tips about csir net
Bhat
what do you mean csir net
Moha
net conducted by csir
Bhat
I don't know yet , is there somebody understand what he said
Moha
can you give me atleast 20 anatomical terminologies that is not common ? its my assignment in my major.
Erika
are you still there?
Erika
😂😂😂
Kshitiz
im asking
Erika
ow Erik I learned medical terminology course past years in my University so I Know alot of words in my mind but I can't destinguash comon words and non comon
Moha
lower abdomen
Teresa
can you help me?
Erika
for what
Arif
give me 20 terminologies that are not common . plz i really need to know. its my assignment in majoy subj
Erika
which have same sounds nd different meanings
Arif
20 terminologies; 1.TSB(tepid sponge bath) 2.OCU(eye) 3.DERMA(skin) 4.LEUK(white) 5.HYDRO(water)6.S/Sx(signs &symptoms)7.TX(treatment)8.Dx(diagnosis)9MAMM(O)breast10.it is(inflammation)
jenelyn
is that anatomical terminology? and yes including the meaning
Erika
yellow marrow has been identified as
Raychelle Reply
Which of the following accurately describe external resipration
Gwendolyn Reply
from the heart to the lungs
Phee
I think it's not outside organ of respiratory all respiratory organ are inside of human body
Moha
diffusion of CO2 and oxygen at a pulmonary capillary surrounding an alveolar sac.
Jeremiah
In other words, from the external environment to the lungs (alveoli) then to the pulmonary capillary then to the heart. So this is a stage of inhalation. inhale = external respiration.
Jeremiah
What kind of discussion
horyaal Reply
what is the function of the placenta
Nchimunya Reply
The placenta acts to provide oxygen and nutrientsto the fetus, whilst removing carbon dioxide and other waste products.
Moha
Also it's the barrier through which the mother is connected to the fetus.
Samuel
I want to discuss... atherosclerosis.., everything about it, about to treatment n prevention at age 50 +
Doctors
Please participate in discussion
Doctors
ok let's discuss now
Moha
first define the word artherosclerosis
Moha
a disease of the arteries characterized by the deposition of fatty material on their inner walls.
tabe
hardening of the arteries, due to fats..
jenelyn
Q = which type of fat utilized for this.., I.e LDL, HDL, TG, VLDL...?
Doctors
Atherosclerosis is a condition of deposition of plaque inside the artries
Arvind
Plaque include such as fat, chalestrol, calcium etc
Arvind
Thank you kumar...., is there any way that we can protect these plaques without any medicines., I. e exercises n food stuffs
Doctors
go to the gym
Moha
what is chylomicrons?
Moha
how can plaque buildup in The angina or vessels ?
Moha
Atherosclerosis is a condition of deposition of plaque inside the artries
Doctors
atherosclerosis can also be caused by tortuousness of arteries with old age as contributing factor.
edward
You tube Prof Fink...he is an amazing lecturer and does a brilliant job on arteriosclerosis
Jacqueline
what are cell
Chigozie Reply
The basic structural and functional unit of any living thing. Each cell is a small container of chemicals and water wrapped in a membrane. 
Yusuf
cell is the structural and functional basic unit of life
Zaid
So every living thing was Created From a Cell
Anthony
from a fusion of two cells , the sperm and the egg
Shikoh
What is the only bone that doesn't have any articulation?
Jimmy
that magical fusion of cells
OBED
why body immune system attack and destroy the body own cell during type 1 diabetes?
Sanamacha Reply
It's an autoimmune disease... targeting the pancreas
Claudia
what are the three genetic defects of pregnancy?
Belinda Reply
structure of fallopian tubes
Akash Reply
what z the role played by the transport system
zinitha Reply
how fats are digested in the human body
Nabukwasi Reply
Fat digestion begins in the stomach but some argue in that it starts in the mouth. Reason is because the sublingual gland secretes an enzyme called lingual lipase. However, this enzyme is not activated until it comes into contact with gastric fluids (HCl). In the stomach, HCl breaks down the lipid..
Jeremiah
due to body heat
Mule
into smaller molecules. Going from a triglyceride and a fatty acid to a monoglyceride and a a fatty acid no longer bound to one another. This is known as lipolysis.
Jeremiah
After lipolysis in the stomach from gastric and lingual lipase, an acidic chyme is produced after stomach churning the bolus. The chyme exits the stomach at the pyloric sphincter and enters the first section of the small intestine known as the duodenum.
Jeremiah
in the duodenum. An alkaline mucus from goblet cells neutralizes the acidic chyme to prevent acid burns. After that, the pancreas and gallbladder secrete a number of enzymes to continue lipolysis. Bile from the gallbladder enters the duodenum via common bile duct. The acinar cells in the pancreas...
Jeremiah
secretes pancreatic lipase after enteroendocrine cells in the duodenum secrete a stimulator hormone called CCK. Cck stimulates bile synthesis and secretion as well as pancreatic lipase.
Jeremiah
Bile emuslifies the lipid, allowing the lipases to continue lipolysis
Jeremiah
this breakdown continues until it reaches the jejunum of the small intestines. At this point, the lipid has been broken down small enough to absorbed into the blood stream. So villi in the jejunum, absorb the contents.
Jeremiah
ileum, the last small intestine region, absorbs anything that wasn't absorbed previously. Like minerals, vitamins, bile salts, water soluble material. Villi here complete that task. Fatty acid and glycerol however, are absorbed by lacteals. small lymph vessels. And are transported to the liver.
Jeremiah
That concludes lipid digestion. Anything else that remains is deficated after it travels through the large intestines.
Jeremiah
parents with blood group AB & 0,,,what will b the blood group of their offspring
imran
what are the different branches of anatomy
Nabukwasi
hopefully that helped.
Jeremiah
which ion is low of blood level?
Ezra Reply
what is coagulation?
feng Reply
liquid turning to solid... blood clots.
Kristy
coagulation : liquid blood into blood clots caused with a coagulant.
jaime
when the blood turn from liquid form to solid
June
it said to coagulate by the action of active plasma protein called *fibrin*
Hassan
I.e liquid inform of blood when to solid
Hassan
it is the process by which blood becomes more viscous or becomes thick
CHRISTOPHER
cloting of blood cells
Kabange
clot of blood
Moses
the process of forming semi solid lumps in a liquid
rida
conversion of blood to solid state
Ezra
semi solid., rather than solid form
Doctors
what is pivot functioned
Ever
to less thefriction
Hirsi
how to calculate the micrograph
Ampong Reply

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Source:  OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 04, 2016 Download for free at http://legacy.cnx.org/content/col11496/1.8
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