Homeostasis

Summary

In this educational video, the concept of homeostasis is explored through the lens of maintaining bodily balance. Key examples include the regulation of blood glucose levels via insulin and glucagon, and body temperature control through mechanisms like vasoconstriction and shivering. The video delves into negative feedback mechanisms that counteract imbalances and positive feedback loops, such as in childbirth and lactation, which amplify responses for essential physiological processes.

Takeaways

• 🌡️ Homeostasis is the body's ability to maintain a stable internal environment by balancing various physiological processes.
• 🔄 Negative feedback mechanisms play a crucial role in homeostasis by counteracting imbalances, such as high or low glucose levels, to restore normal conditions.
• 💉 The pancreas is a key organ in glucose homeostasis, releasing insulin to lower high blood sugar and glucagon to raise low blood sugar.
• 🚨 In response to high blood glucose, pancreatic alpha cells produce insulin, which signals cells to absorb glucose, reducing blood glucose levels.
• 📉 Conversely, low blood glucose triggers the pancreas to produce glucagon, which stimulates the liver to release glucose into the bloodstream.
• 🌡️ Body temperature regulation is another example of homeostasis, with the hypothalamus acting as the control center for thermoregulation.
• ❄️ In cold conditions, the body conserves heat by vasoconstricting blood vessels and inhibiting sweat production, while shivering generates heat.
• 🔥 During hot conditions, the body cools down by vasodilating blood vessels to increase heat radiation and by stimulating sweat production for evaporative cooling.
• ➕ Positive feedback mechanisms, unlike negative feedback, amplify the initial response and are crucial in processes like childbirth, where uterine contractions are intensified.
• 🍼 Suckling by a baby is a positive feedback stimulus that leads to the production and ejection of milk in the mother's breast, facilitated by prolactin and oxytocin.

Q & A

What is homeostasis?

Homeostasis is the state of maintaining a balance within our body systems to keep our physiological processes stable.

How does the body maintain glucose balance?

The body maintains glucose balance through negative feedback mechanisms. High glucose levels trigger the pancreas to release insulin, which helps cells absorb glucose. Conversely, low glucose levels stimulate the release of glucagon, which prompts the liver to release glucose into the bloodstream.

What is the role of the pancreas in glucose homeostasis?

The pancreas plays a crucial role in glucose homeostasis by producing insulin in response to high glucose levels and glucagon in response to low glucose levels, thereby regulating blood sugar.

What is the function of insulin in the body?

Insulin is a hormone that signals cells to open protein channels and absorb glucose from the blood, thus lowering blood glucose levels.

How does the body respond to low glucose levels?

In response to low glucose levels, the pancreas releases glucagon, which signals the liver to convert glycogen into glucose or produce glucose through gluconeogenesis, and then release it into the bloodstream.

What is a negative feedback mechanism?

A negative feedback mechanism is a process that counteracts a change in conditions to restore balance. It is like a control response that works to maintain homeostasis by reducing the effect of a stimulus.

Can you explain the process of thermoregulation in the body?

Thermoregulation involves the body's response to temperature changes. In cold temperatures, the body constricts blood vessels and inhibits sweat production to reduce heat loss. In hot temperatures, it dilates blood vessels and increases sweat production to promote heat loss through evaporation.

What is the role of the hypothalamus in temperature regulation?

The hypothalamus acts as the control center for temperature regulation, receiving signals from thermoreceptors and sending efferent signals to effectors like blood vessels and sweat glands to maintain a stable body temperature.

What is a positive feedback mechanism, and how does it differ from a negative feedback mechanism?

A positive feedback mechanism amplifies the initial response rather than counteracting it. It is different from a negative feedback mechanism, which works to restore balance by countering changes. Positive feedback is often involved in processes that require a self-reinforcing cycle, such as the birthing process or blood clotting.

How does the body initiate the birthing process through positive feedback?

During the birthing process, the stretching of the cervix activates stretch receptors in the uterus, which send signals to the hypothalamus and posterior pituitary to release oxytocin. Oxytocin stimulates uterine contractions, which further stretch the cervix, creating a positive feedback loop that continues until the baby is born.

Outlines

00:00

🔍 Introduction to Homeostasis

The video begins with an introduction to the concept of homeostasis, which is the body's ability to maintain a stable internal environment. The speaker emphasizes the importance of supporting the creation of educational content by liking, commenting, and subscribing. They also mention that additional notes and illustrations are available on their website. The main idea is to understand how the body maintains balance within its systems, using examples to illustrate the concept of homeostasis.

05:02

💉 Negative Feedback Mechanism in Homeostasis

This section delves into the negative feedback mechanism, a key process in maintaining homeostasis. The speaker uses the example of blood glucose levels, explaining how high or low glucose acts as a stimulus that triggers a response from the pancreas. High glucose levels lead to the production of insulin, which helps cells absorb glucose and lower blood glucose levels. Conversely, low glucose levels trigger the release of glucagon, which signals the liver to release glucose into the bloodstream. The speaker breaks down the process into stimulus, receptor, control center, efferent signal, effector, and response, providing a clear understanding of how negative feedback works to maintain balance.

10:03

🌡️ Body Temperature Regulation

The speaker shifts the focus to body temperature regulation, another aspect of homeostasis. They explain how the body responds to extreme temperatures through thermoreceptors in the skin, which send signals to the hypothalamus. In response to cold, the hypothalamus triggers vasoconstriction of blood vessels and inhibits sweat production to reduce heat loss. It also stimulates shivering in muscles to generate heat. In contrast, hot temperatures lead to vasodilation and increased sweat production to promote cooling through evaporation and reduce heat production by inhibiting shivering. This example further illustrates the negative feedback mechanism in action.

15:04

🤱 Positive Feedback Mechanisms

The discussion moves to positive feedback mechanisms, which amplify the initial response rather than counteract it. The speaker provides three examples: the birthing process, lactation, and blood clotting. In the birthing process, the stretching of the cervix during labor stimulates the release of oxytocin, which strengthens uterine contractions to aid in childbirth. During lactation, suckling stimulates the release of prolactin and oxytocin, which promote milk production and ejection. Lastly, in the case of blood vessel injury, platelets aggregate at the site of injury, releasing chemicals that attract more platelets, forming a clot. These examples demonstrate how positive feedback can be beneficial in certain physiological processes.

20:05

🩸 Platelet Plug Formation and Conclusion

The final part of the script focuses on the positive feedback mechanism involved in blood clotting. When a blood vessel is injured, platelets are signaled to aggregate at the site, forming a plug. This process is self-amplifying as more platelets are attracted to the site, further strengthening the clot. The speaker concludes by summarizing the key points about homeostasis, emphasizing the importance of understanding both negative and positive feedback mechanisms in maintaining the body's balance. The video ends with a reminder to engage with the content and a tease for future videos.

Keywords

💡Homeostasis

Homeostasis refers to the body's ability to maintain a stable internal environment despite changes in external conditions. It is central to the video's theme as it explains how the body achieves a state of balance through various mechanisms. For instance, the video discusses how the body maintains a balance of glucose levels and body temperature, which are critical for homeostasis.

💡Negative Feedback Mechanism

A negative feedback mechanism is a process that counteracts deviations from a set point to maintain homeostasis. The video uses the example of glucose regulation, where high glucose levels trigger the pancreas to release insulin, which helps lower blood glucose, thus countering the initial imbalance. This mechanism is crucial for maintaining stability within the body's systems.

💡Glucose

Glucose is a simple sugar that serves as the body's primary source of energy. In the context of the video, glucose levels are a key factor in homeostasis. The body uses negative feedback mechanisms to regulate glucose levels, ensuring they do not get too high or too low, which could be harmful.

💡Insulin

Insulin is a hormone produced by the pancreas, which plays a critical role in glucose regulation. As explained in the video, when blood glucose levels are high, insulin is released to signal cells to take in glucose, thereby reducing blood glucose levels and contributing to homeostasis.

💡Glucagon

Glucagon is another hormone produced by the pancreas, which is released when blood glucose levels are low. The video explains that glucagon stimulates the liver to convert stored glycogen into glucose or to produce glucose from other molecules, thus raising blood glucose levels and helping to maintain homeostasis.

💡Hypothalamus

The hypothalamus is a region of the brain that plays a key role in regulating body temperature, among other functions. The video describes how the hypothalamus acts as a control center for homeostatic mechanisms, such as responding to cold or hot temperatures by sending signals to effectors to adjust blood vessel constriction and sweat production.

💡Thermoregulation

Thermoregulation is the process by which the body maintains a stable internal temperature. The video discusses how the body uses negative feedback mechanisms to regulate temperature by adjusting blood flow to the skin and sweat production in response to cold or hot external conditions.

💡Vasoconstriction

Vasoconstriction is the narrowing of blood vessels, which helps to conserve heat by reducing blood flow to the skin. The video explains that in response to cold temperatures, the hypothalamus triggers vasoconstriction to prevent heat loss and maintain body temperature.

💡Evaporative Cooling

Evaporative cooling is a process that helps to cool the body when it is overheated. The video describes how the body increases sweat production, which then evaporates from the skin, taking heat away from the body and thus lowering body temperature.

💡Positive Feedback Mechanism

A positive feedback mechanism is a process that amplifies an initial stimulus or condition, often leading to a significant change. Unlike negative feedback, which seeks to restore balance, positive feedback mechanisms can lead to a rapid progression towards a new state. The video provides examples such as the birthing process, where the stretching of the cervix triggers the release of oxytocin, which further stimulates uterine contractions, aiding in the delivery of the baby.

💡Oxytocin

Oxytocin is a hormone that plays a crucial role in the birthing process and lactation. The video explains that during childbirth, oxytocin is released in response to the stretching of the cervix, leading to stronger uterine contractions that help push the baby out. Similarly, during lactation, oxytocin stimulates milk ejection in response to the baby's suckling.

Highlights

Homeostasis is the state of balance within body systems.

Negative feedback mechanisms counteract imbalances, such as high or low glucose levels.

The pancreas plays a crucial role in glucose homeostasis by producing insulin and glucagon.

Insulin signals cells to absorb glucose from the blood, reducing blood glucose levels.

Glucagon stimulates the liver to release glucose into the bloodstream, increasing blood glucose levels.

The hypothalamus is a central regulator in homeostasis, responding to temperature changes.

Thermoregulation involves vasoconstriction and sweat inhibition in cold temperatures to conserve heat.

In hot temperatures, the body increases heat loss through vasodilation and sweat production.

Positive feedback mechanisms amplify responses, unlike negative feedback which counteracts them.

The birthing process is an example of positive feedback, where uterine contractions are amplified.

Oxytocin is a hormone that plays a key role in uterine contractions during childbirth.

Suckling by a baby is a stimulus that triggers milk production and ejection via prolactin and oxytocin.

Platelet plugs are an example of positive feedback in blood clotting, where the response is amplified.

Homeostatic mechanisms are essential for maintaining a balance in various body parameters like blood pressure and pH.

Disease processes can disrupt homeostatic mechanisms, leading to imbalances in the body.

Understanding homeostatic mechanisms is crucial for medical professionals to diagnose and treat diseases.

Transcripts

foreign

what's up Ninja nerds in this video

we're going to be talking about

homeostasis before we get started if you

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do that also you guys want some awesome

notes some illustrations to check out

while we kind of go through this lecture

together go down the description box

below to take you to our website where

we have some great notes and

illustrations but let's talk about

homeostasis when we talk about

homeostasis what is homeostasis it's

basically the state of balance right so

you want to be able to maintain a

balance within our body systems and so

one of the best ways that I think of

kind of explaining homeostasis is

utilizing examples I think it'll kind of

give you the Bare Bones information

it'll help you to be able to truly think

about this in a very specific

pathophysiological or physiological way

so when we talk about homeostasis is

trying to be able to maintain a degree

of balance so whenever something is out

of balance and we'll use two particular

examples some some things like glucose

the glucose levels are too low or

they're too high well that's a state of

imbalance how do we help to be able to

maintain that balance one of the ways

that we help to be able to counteract

the imbalance or to counteract the

imbalance response is we use something

called the negative feedback mechanism

so I want you to think about the

negative feedback system or the

mechanism as the counter response

the counter response if you will

so in other words there's some type of

problem in other words there is a

stimulus if you will what is this

stimulus the stimulus in this particular

example that we're going to be referring

to is glucose so glucose we obviously

wanted to be able to maintain a normal

level and that varies but generally if

the glucose levels are too

high so the glucose levels within the

blood are too high this is a particular

stimulus for our body

and what happens is this high glucose

will then go to a particular organ in

our body called the pancreas

when it goes to the pancreas there's

different types of cells we call them

pancreatic alpha cells right and on

these pancreatic alpha cells they have

these like little receptors on them some

of these receptors here we call them

glut receptors and what these glut

receptors do is is when glucose actually

binds to them they kind of move the

glucose into the cell and that's the

signal to the cell hey hey glucose

levels are really really high pancreas I

need you to respond to this high glucose

level and so the pancreas as a response

to this high glucose level will make a

very special type of hormone

and this hormone is called

insulin

and what insulin does is is insulin is

the signal that then goes and binds onto

these like little receptors on different

cells in the body

when it binds onto these receptors it

tells this cell hey I need you to open

up these like protein channels and start

shuttling in glucose into the cell

and so what it does is it opens up these

channels and starts pulling glucose out

of the blood and into the cell

now as a response to that think about

this my friends high glucose was the

stimulus

okay high glucose is going to be the

stimulus

then a receptor has to pick up that

signal this will be the Glutton

receptors

the glut receptors has to send signals

to your pancreas so it's going to send

afferent signals into your actual

pancreas it's going to send information

to the pancreas say hey pancreas that

blood sugar will be high I need you to

make insulin so then the pancreas will

be the control center if you will

the pancreas will then send an efferent

signal via the insulin

the insulin is then going to go and act

on an effector

in this case these tissue cells

and when it acts on the effector it's

going to produce a particular response

and what is that response to shuttle

glucose into these cells and what's the

overall effect out of all of this the

overall effect is if I pull glucose out

of the blood into the cells I'm going to

lower

my blood glucose levels and that's a

homeostatic mechanism

and the same concept what if the glucose

levels are too low

so now we go to the opposite situation

here where the glucose levels are too

low well this is an abnormal type of

change within the body homeostasis we

want to try to maintain a balance so the

negative feedback system will develop a

counter response the glucose will then

be what the stimulus it'll then go and

do what tell these glut receptors that

are present on the pancreas

that hey

glucose is low

if the glucose is low then the pancreas

will respond to that and say oh okay if

the glucose is really really low I need

to be able to figure out a way to

increase the glucose so then what it

does is it makes a hormone

and this hormone is called glucagon

glucagon

and while glucagon does is it binds onto

these like little receptors on your

liver tells the liver hey liver we need

some glucose in the bloodstream so what

the liver does is it breaks down big

molecules present inside of the actual

liver called glycogen or takes other

molecules like amino acids and lactate

and fatty acids and turns it into

glucose

via a process called gluconeogenesis or

glycogenolysis and then pushes this

glucose

into the bloodstream

so if you think about it

the low glucose was the stimulus

it will then act on the glut receptor

which is going to be the receptor

the pancreas will be the control center

who will then release glucagon

glucagon will then be the

efferent signal to another particular

Target organ or an effector that

effector is going to be the liver

and the overall responses is going to

put more glucose into the bloodstream

and what will happen my friends the

glucose will increase

so that is the concept that I want you

guys to understand when we're talking

about negative feedback mechanisms

but maybe you're still a little tough

it's still tough to kind of okay I still

I get it I get it Zach but I'm not there

yet let me give you another example to

really solidify

so now what we're going to do is we're

going to say okay

I'm not going to talk about blood

glucose now I'm going to talk about body

temperature because body temperature is

a big thing as well I really want to be

able to maintain a normal body

temperature

so let's say that I expose one person to

very cold temperatures

and I expose another person to very hot

temperatures our body wants to be able

to maintain a certain degree of

homeostasis we don't want to be too cold

we don't want to be too hot we don't

have too high glucose levels and we

don't have to have two low glucose

levels

so what happens is this cold temperature

will stimulate something called

thermoreceptors so the cold temperature

is the stimulus the hot temperature is

also a stimulus

it'll then hit these thermoreceptors in

the skin

when you hit the thermoreceptors in the

skin these are coupled with nerves and

it'll send signals

toward your central nervous system this

is your afferent signals and it'll go to

a very specific structure in your CNS

you know what this structure is called

here it's called the hypothalamus so

we're just going to represent this right

here as your hypo

thalamus it's going to be the same thing

for this structure right here

the hypothalamus will then respond to

this particular signal that hey there's

really cold temperatures

and then what it'll do is it'll send

efferent signals down through your

spinal cord

out through particular nerves

that go and send signals to these

effectors to produce a clinical response

what are those effectors well one of

them is the blood vessels

if there's really cold temperatures I

don't want the blood vessels on my skin

to be dilated because if they're dilated

a lot of blood flow goes there and two

things happen with increasing blood flow

to the skin one is it irradiates heat so

that's going to be a way of losing heat

I don't want to lose heat so I don't

want to vasodilate them I want to

vasoconstrict them second thing is if

lots of blood flow go through here it

helps these glands to be able to make

sweat and sweat will then coat the skin

and then allow for evaporative cooling I

don't want to cool my body I'm already

too cold so what I want to do is

I want to vasoconstrict this vessel so

I'm going to cause a Vaso

constriction of the cutaneous vessels

and then I'm going to inhibit

sweat gland production I'm going to

cause a vasoconstriction response and

I'm going to inhibit

sweat

production

so this will inhibit or reduce

evaporative cooling

the other concept is I'm going to send

signals to my muscles you know my

skeletal muscles when they helped when

you know whenever we shiver you guys

ever been in the cold temperatures you

shiver when you shiver it actually

generates ATP it's these incomplete kind

of contractions and so what I really

want to do is I want to help to kind of

cause and increased stimulation to these

actual skeletal muscles and I want to

produce a very profound shivering

response to counteract the cold

temperatures and what this will do is

this will increase

heat production

and this will help to counteract the

cold temperature and the same thing a

vasoconstriction and inhibiting a sweat

production will do what this effect will

actually inhibit

evaporative

Cooling

and again that will do what

inhibit the actual cold temperature and

that's the goal is to counteract

and the same concept my friends

hot temperatures

hits the thermoreceptors stimulates the

thermoreceptors since afferent signals

up through the nerves to your

hypothalamus hypothalamus which is the

control center says okay body's way too

hot I'm going to send efferent signals

down to the effector organs so that we

can actually develop a clinical response

and then that clinical response will

hopefully Lord will encounter act the

stimulus the hot temperatures

so now all I got to do is do the

opposite here

I want to vasodilate because of a

vasodilate I get a lot of blood flow

through my skin which radiates heat

that's good so I want to cause Vaso

dilation

and then if I vasodilate my blood

vessels also I'm going to get a lot of

blood flow and I'm also getting a lot of

sympathetic Supply here to my glands and

so if that's the case what I'm going to

do is I'm going to increase my sweat

production

and if I increase increase

my sweat production then what I'm going

to do is I'm going to have this nice

layer of sweat here and whenever the air

kind of hits that it's going to allow

for an evaporative cooling response and

so I want to stimulate sweat production

and the combination of these two

particular processes will do what

it'll allow for stimulation of

evaporative cooling

and that is a great thing because it's

going to start cooling the body and if I

cool the body what am I going to do I'm

going to

inhibit my body's increase in the

internal body temperature

same concept I'm going to I'm actually

going to do what to my muscles do I want

them to shiver now to generate heat no I

don't want them to shiver so I'm going

to inhibit the actual shivering response

so if I inhibit shivering I won't be

able to generate a lot of heat so then

that'll do what that'll decrease

the heat production from my muscles and

if I decrease the heat production

that'll decrease the increase in the

internal body temperature and that's the

counteractive response it's the same

concept

these are

my stimulus

these are

my receptors

the blue and red

are the afferent signals the signals

coming up to this structure here the

hypothalamus

is my control center

the efferent signals going down to my

actual effector organs from these points

here

is my efferent signals oops efferent

signals apologize

and then the last Point here is going to

be

my effectors

which is going to be these particular

structures here

and then this would be the last part

here which would be the effectors which

would be the skin the blood vessels and

the muscles that's the concept that I

want you guys to understand here with

the negative feedback system but that's

not the only thing that plays a role in

homeostasis we also have something

that's kind of interesting called the

positive feedback let's talk about that

all right so positive feedback mechanism

so when we talk about this again

homeostasis is maintaining a state of

balance many different disease processes

right they don't allow for that

counterbalance so in situations where

maybe the glucose is too high maybe the

problem with them not being able to

bring the glucose down is they have a

problem with insulin right and so that's

kind of the whole process when there is

a breakdown in the homeostatic mechanism

it's usually a disease process

now negative feedback is to counteract a

response so low glucose high glucose low

temp high temp we get the point you can

continue to go down the list high blood

pressure low blood pressure high pH load

pH we can go down a list of all types of

abnormalities and how our body maintains

that balance

the feedback is a little bit different

and this one you're amplifying the

initial response which is odd right so

you often don't really kind of want this

type of response so

what situations which are actually truly

helpful for you when you're to in your

exam to remember positive feedback

mechanisms we're actually amplifying the

response to the initial stimulus would

actually be a good thing

the first one is the birthing process

that baby be stretched in the cervix

right and so during the birthing process

you be stretching that cervix all the

way out here right so there's a great

degree of stretching during the birthing

process

that stretching

of the cervix

is a very powerful stimulus

that activates

stretch receptors within the uterus

these stretch receptors then send

afferent signals to your control center

and in this case that control center

guess what it is the hypothalamus and

the posterior pituitary

so here in the control center we have a

structure here called the hypothalamus

and another really important structure

that the hypothalamus influences is

called the posterior pituitary

and what happens is the hypothalamus

will stimulate the posterior pituitary

who will then release something called

oxytocin that's our efferent signal

oxytocin will then move down

and bind onto particular types of

receptors on the muscle of the uterus

now if a baby is stretching the cervix

of the uterus

and you're getting ready to have birth

would you want to not contract and help

to push the baby out or would you want

to contract to help to push the baby out

that's the goal right so we actually

don't want to kind of prevent any kind

of like issues here we actually want to

continue to cause contraction of the

uterus that'll push the baby further and

guess what it's going to do stretch the

cervix even more that's amplifying the

response so what oxytocin will do is

it'll stimulate uterine contraction and

it'll try to propel the baby further

down into the cervix which can be

jamming that cervix out even more so

you'll increase the stretch of the

cervix you'll increase the stimulation

of the stretch receptors increase the

stimulation of the hypothalamus the

posterior pituitary continue to increase

more oxytocin increase uterine

contraction and do this process until

what

until the baby is expelled all right

that's the very really important process

for birth

there's two more examples that I think

are really helpful

and again just keep thinking about this

process you always have a stimulus a

receptor an afferent signal a control

center an efferent signal and then the

effector it's been the same thing we've

kind of learned it throughout the

process

but the next mechanism is here we have a

baby so here we have the breast tissue

right here's a baby who's suckling on

the breast

right so the stimulus is suckling so

this is usually during the lactation

process right so the stimulus is

suckling what it does is the cycling

activates certain types of tactile or

mechanoreceptors around the breast

that then sends signals down the nerves

connected to the actual mechanoreceptors

to what to the hypothalamus and the

pituitary structures what is this again

the hypothalamus

and the anterior pituitary

I'm going to put anterior pituitary here

and there's also another structure

called the posterior pituitary

now anti-pritary makes a very specific

hormone

and this one is called

prolactin

and the poster pituitary we already know

which one that Mo makes

oxytocin

the difference here is there's two

efferent signals right so the stimulus

was the suckling the receptor was the

mechanoreceptor the nerves going to the

hypothalamus is going to be the affair

signal the hypothalamus anterior

pituitary poster pituitary or the

control center the prolactin the

oxytocin are going to be the effectors

or the efferent signal I apologize

efferent signal the effector will be the

breast tissue

when prolactin

is released what does it do to the

actual breast tissue to produce a

response it actually stimulates

these glands to make milk so it actually

stimulates milk

production

so now these glands here in the breast

tissue are going to fill up

with the good old milk

okay

the next thing is that oxytocin is going

to stimulate milk ejection so it's going

to stimulate milk

injection we also call this the milk

letdown reflex or the letdown reflex so

now it's going to stimulate

myoepithelial cells around the gland and

Papu

we're going to shoot some of that milk

right into the baby's gullet

and so from here the actual response is

going to be prolactin and oxytocin

stimulating what these we're going to

draw with little dots here here's the

prolactin here's the oxytocin prolactin

will stimulate the milk production

oxytocin will stimulate

milk ejection and that's going to be the

response the effector is the actual

mammary glands of the breast tissue

that's the concept there all right if

that's not enough let's do one last one

here we have a stimulus the stimulus

is there's a hole

or a tear

and a blood vessel right whatever that

reason may be there's a hole in the

blood vessel there

when the hole in the blood vessel occurs

certain chemicals are released

that signaled the platelets and tell the

platelets hey platelets there's an

injury here so the platelets then

respond to that

and they have little receptors on them

that kind of take off that information

they say okay I'm going to come and

stick to you so then the platelets stick

to this actual hole in the blood vessel

when they stick to the hole in the blood

vessel the next thing that they do is

they release more chemicals

and these chemicals tell more platelets

hey there's a lot of kind of like injury

over here a lot of platelets taking here

can you come and stick to this platelet

plug as well and they come in stick and

again more platelets will continue to

stick here and they'll release more

chemicals that'll tell more platelets to

again come and stick and you see the

whole point was there was a stimulus but

what did we do with each one of these

particular scenarios we Amplified the

response that's another concept of a

patient developing a positive feedback

mechanism and this is via what's called

the platelet plug

so the platelet plug

and the same thing with the suckling

mechanism the trigger was the baby

suckling

what it's going to happen is it's going

to cause this baby to do what send

signals all the way up to the

hypothalamus to produce oil hormones

that will cause milk production the milk

will then be ejected into the baby's

mouth what's the baby going to continue

to keep doing

suckling so that it can continue to

stimulate these receptors send more

signals to make more milk it's a

constant amplifying process that's the

big thing to take away from this and

that finishes our discussion here on

homeostasis I hope that you guys liked

and hope it made sense as always until

next time

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