Homeostasis Hints

specific objectives: yesteryear the terminate of this lesson, the students should live able to

a.     define homeostasis

b.     state the homeostatic organs

c.      describe the role of the kidney inwards homeostasis

d.     describe the role of the liver inwards internal control

e.     State the role of hormones inwards rule of internal residue

f.       List the institute hormones together with their functions.

Homeostasis is the maintenance of a fairly constant internal torso residue of an organism; it is the rule of the torso (internal) inwards gild to ensure survival. Organisms ask to maintain their environs inside for certain limits that is necessary for survival. The maintenance of this residue is achieved yesteryear particular organs of the torso called regulatory organs of homeostasis organs. These organs rely on a combine endeavor of the 2 information systems of the torso to piece of work v1z

-          Nervous system

-          Endocrine system

       Step 2: homeostaTIC organs

1.     Kidney

2.     Liver

3.     Skin

4.     Endocrine glands (hormones)

A centre inwards the torso (brain) controls together with determines the work of activity of these organs. This centre is called the Homeostasis Centre. It is the hypothalamus.

Materials they regulate include:

-          Water

-          Salt

-          Irons/minerals salts

-          Hydrogen together with concentration (PH)

-          Temperature

-          Nutrient degree

-          Sugar

Any imbalance inwards these parameters initiates a homeostasis procedure which nullifies the alter yesteryear increasing or decreasing unopen to other parameter

Step 3:       the  Kidney.

The kidney is both excretory together with homeostatic inwards function

Shape   –          beans shape

Size                  -           10cm x 5cm x 2.5cm

Colour -           reddish brown

Position            -           t12-l3

Weight -           125 – 500gms

It is a bilateral organ having the medial surface indented to shape the human where structures go into or go out the kidney.

Blood render – from the renal artery together with renal vein.

                                 

The primary cells that brand upwards the kidney are called the nephron each kidney has most three 1000000 nephrons. The kidney has an outer layer called the cortex together with inner layer called medulla. The nephron is the functional cells of the kidney made upwards of a arrangement of tubules. Its constituent include.

-          A funnel shaped oral fissure called bowman’s capsule each of which receives a tuft of the renal vessels called glomerulus.

-          Proximal convoluted tubule  

-          Descending sparse loop of Hence (U-shaped tube)

-          Ascending thin/thick loop of Hence

-          Distal convoluted  tubule

-          Collecting tubules

-          A network of afferent together with efferent arterioles forming a rich peritubular capillary bed

Period 2:  wed 16/05/18

Functions of the kidney.

-          Removal of excretory waste matter (excretion)

-          Osmorgulation

As an orsmoregulator, the kidney controls the amount of H2O inwards the body. It controls the amount of tabular array salt (Na+K+cl). It controls the amount of acid (H+, Hc03).

Step 4:

HOW DOES THE KIDNEY REGULATE WATER

Water is lost from the torso or organisms through sweating, urination, faeces together with expired air. Water is gained via drinking together with eating. These 2 routes must residue each. On hot days, they torso loses much H2O together with excrete a small-scale amount of concentrated urine. On mutual frigidity days, nosotros sweat less together with excrete large amount of dilute urine. When the torso excrete small-scale amount of H2O or sweat profusely, the osmotic pressure level of blood rises equally a resultant of ascent inwards solute content of blood. This imbalance is picked upwards yesteryear detectors called osmo receptors inwards the hypothalamus.

The hypothalamus gives a command to the pituitary gland for the unloose of ADH (anti diuratic hormones)

ADH released reaches the proximal together with distal convulated tubules together with effort increment permeability of the tubules for water. This causes increment reabsorption of H2O dorsum to blood hence reducing the osmotic pressure level to its normal level. As presently equally this happens, the detectors send dorsum signals that initiates the inhibition of farther production of ADH. This keeps the blood book constant again. The torso thence uses a negative feed dorsum machinery to maintain its osmotic pressure level together with H2O balance.

Feed dorsum machinery is only regulating a procedure using its products.

Step: 5

HOW DOES THE KIDNEY REGULATE SALT:

The kidney makes utilization of hormones called ALDOSTERONE (from adrenal Cortes). Aldosterone is a tabular array salt upwards taker i.e it stimulates the active absorption of tabular array salt (sodium ion) at the distal convoluted tubules together with the collecting tubules hence when in that place is an increment loss of tabular array salt yesteryear the torso via excretion or sweating, the kidney receives an influx of aldosterone which causes the distal tubules to actively go permeable to Na+ thereby reabsorbing the tabular array salt dorsum to blood. The opposite is the representative when tabular array salt concentration inwards blood is high.

Step 6:

HOW DOES THE KIDNEY REGULATE pH

Blood is kept at a PH of 7.4. the torso makes utilization of bicarbonates (HC0₃) inwards the torso equally buffers keeping the PH betwixt 4.5 together with 8.5 (of urine).

When the H+ concentration increases, the kidney releases to a greater extent than HC0₃  which combines alongside the H+ to eliminate them thereby causing a decrease inwards the let out of HC03 are removed causing the blood to live less alkaline

Period 3: Thurs 17/05/18

Diseases of the Kidney

1.     Glomerular nephritis

2.     Kidney stone

3.     Diuresis

4.     Oedema/dropsy

5.     Kidney failure

Step 7:  role of liver inwards Homeostasis

The liver is the largest mammalian organ alongside a weight of 3kg – 2.25kg m an average adult man & woman. It has an average weight of 1.25kg.

The liver is positioned below the thoracic diaphragm together with higher upwards the stomach. It occupies the mass of the correct hypochondrum together with the epigastric regions alongside a petty orientation to the left.

LOBES: the liver is divided into 2 large lobes yesteryear a ligament (falciform) viz

-          Right hepatic lobe

-          Left hepatic lobe

Anatomically iv lobes are seen viz

-          Left hepatic lobe

-          Right hepatic lobe

-          Quadratic lobe

-          Caudate lobe

Each lobe of the liver is farther divided into functional unit of measurement called liver lobules, each lobules is made upwards of liver cells called hepatocytes. Liver defensive cells called kupffer cells together with a bile canaliculi. Also introduce inwards each lobules is the portal triad containing a branch of the hepatic artery portal vein together with bile duct leaving into the sinusoids.

            An agreement of the functions of the liver volition assist to know the role of the liver inwards homeostatic maintenance. It receives 2 blood render (Hepatic artery together with Hepatic portal vein)

Step8: Functions of the Liver

1.     Regulation of blood glucose. The liver regulates the degree of blood refined saccharify yesteryear either converting excess glycogen to glucose or yesteryear conversion of excess glucose to glycogen. This is achieved using the homeostatic procedure involving the pancreatic islets of Langerhans whose beta cells produces insulin together with glycogen insulin acts on glucose to metabolize it.

Glucagon acts on glycogen to convert it to glucose.

2.     Conversion of glycogen to glucose.

The liver converts excess glycogen to glucose when the torso is inwards high need for energy. This is done using the hormone glucagon from the pancreatic cells.

3.     Deamination of proteins.

The liver through its numerous metabolic enzymes convert excess ammo acid to ammonia together with consequently duo it to CO2 inwards the Ornithine wheel (Urea cycle) to shape urea which is so eliminated from the torso via the kidney.

Ureotelics excrete proteins equally urea. Hence the enzymatic breakdown of ammo acids to ammonia together with urea for excretion is deamination.

4.     Detoxification:

The liver breaks downwardly harmful or poisonous substances into harmless substances using it numerous enzymes eg catalase which catalyses the breakdown of hydrogen peroxide to H2O together with oxygen 2H₂0₂                         2H₂0+0₂

Most drugs are potential poisons if non handled yesteryear the liver.

5.     Production of bile: the liver destroys quondam carmine blood cells together with extract the haemoglobin moiety. It converts it into atomic let out 26 together with globulin. The yellowish pigment; bilirubin is used to make a thick yellowish liquid called bile. This contains water, bile salt, bile acids, inorganic ions together with cholesterol.

The bile salts together with acids business office to interruption downwardly fatty inwards the procedure called Emul sification. Bile is transported via bile canaliculi to the cystic duct where it enters the gall bladder for storage.

6.     Storage vitamins.

The liver is a shop for both fatty soluble together with H2O soluble vitamins eg A,D & B12

7.     Production of heat

8.     Metabolism of fat

9.     Metabolism of carbohydrate

10.  Formation of blood together with storage of blood

Liver Diseases

1.     Liver cirrhosis

2.     Bile stone

3.     Viral hepatitis

4.     jaundice

5.     Cancer

Evaluation

1.     What is homeostasis

2.     In v points province how the kidney regulate H2O balances

3.     State vi functions of the liver

Summary:

The maintenance of a fairly constant internal residue is done yesteryear the kidney, liver, peel together with the hypothalamus using the hormones equally managers. The kidney regulate water, salt, PH piece the liver is involved inwards metabolism.

Homework:

1.     Draw together with label the heart-lung machine

2.     Describe its working principles

Sub topic: hormones

Specific objectives: yesteryear the terminate of this lesson, the students should live able to

a.     State the role of hormones inwards rule of internal balance

List the institute hormones together with their functions

Role of Hormones inwards homeostasis

Step 1: Animal Hormones

Hormones are chemic substances provided yesteryear endocrine glands inwards reply to for certain stimulus, transported through the blood current to target organs where they exert their effects. Hormones practise non move through ducts hence their sources are called ductless glands.

Effects include

-          Speeding upwards (excite)

-          Slow downwardly (inhibit)

-          Alter the activities of target organs

Step 2: Site together with location

Diagram showing relative position

And place of endocrine glands

Step 3: wednesday

The diverse endocrine glands together with their hormones equally follows:

-          Pituitary gland (master hormone)

-          thyroid gland  (thyroxine together with calcitonin & T3)

-          Parathyroid gland  (Parathomones)

-          Adrenal gland (adrenaline)

-          Ovary  (oestrogen together with progesterone)

-          Testis (testosterone)

-          Thymus  (thymosine)

The pituitary gland develops from 2 embryonic source hence the differences inwards the 2 parts. It has 2 parts viz

-          Anterior

-          Posterior

The hormones of the posterior constituent include

1.     ADH (anti diuretic hormone)

2.     Oxygen

ADH is responsible for reabsorption of H2O yesteryear increasing the permeability of the kidney tubules. It besides increases the blood pressure level yesteryear causing the activation of the renin-angiotensin arrangement (RAS) which directly causes the constriction of the arterioles.

    Oversecretion:

Oversecretion of ADH causes maximum reabsorption leading to oligouria (reduced urine passage)

Undersecretion: causes diuresis, dehydration together with loss of electrolyte

Oxygen:

This is a polypeptide hormone. It is incorporated into Pitocin (birth inducing injection) to initiate labour.

(1)   It functions inwards the contraction of the uterine muscles at labour (2) it induces the unloose of milk from the thorax yesteryear contracting the musculus of the breast.

OVERSECRETION:

-          Can Pb to spontaneous abortion

Undersecretion:

-          Effect of undersecretion is seen inwards reduced contraction during labour together with may warrant induced labour or CS it may besides Pb to delayed unloose of milk after labour

EVALUATION

-          Define a hormone

-          Using a diagram demo the relative position of all v endocrine gland inwards humans

Step 4: Thursday

Anterior hormones:

They include:

FSH      -           follicular stimulating hormone

LH        -           luteinizing hormone

Prolactin          

Growth hormone

Thyroid stimulating hormone

FSH

-          Responsible for ripening of eggs yesteryear stimulating the ovary

-          Enhance ovulation

-          Stimulates ovary to make oestrogen

-          Enhance evolution of 2^o gender activity characters

-          It plays a role inwards menstruation

LH

-          Enhances the formation of corpus luiten

-          Enhances the evolution of 2^o gender activity characters

-          Induces the production of progesterone inwards female

-          Stimulates ovulation

Prolactin:

-          Responsible for milk production inwards females

Growth hormone:

-          Responsible for growth inwards long bones

-          Promotes poly peptide synthesis together with increment metabolic charge per unit of measurement inwards cells

Oversecretion = Gigantism = Acromegally

Undersecretion = dwarfism

Thyroid Hormone (THYROXINE)

-          It controls torso metabolic rate

-          It enhances metamorphosis inwards toad

-          It stimulates growth together with evolution inwards immature animals

Oversecretion: - nervousness, irritability, increment pump rate, weightless, exophtalmic goitre exophthalmos, increment IBMR, hyper thyrodism

Undersecretion = cretinism inwards infants

                                 Hypothyroidism & myxedema inwards adults

Leading to hyperplastic goitre

Calcitonin helps inwards lowering blood calcium

Parathomones increment blood calcium.

Pancreatic hormones:

Insulin: produced yesteryear islets of Langerhans

Function – converts excess glucose to glycogen

Oversecretion – depression blood refined saccharify (hypoglycemia

                           = increment together with incessant hunger

Undersecretion – diabetes mellitus

Glucagon: converts excess glycogen to glucose

Adrenalin: besides called emergency hormone. It is the tight together with low-cal hormone

Function:          prepares the muscles for action

                        Prepares the torso for emergency

                        It besides business office equally a neurotransmitter

Over secretion – causes anxiety, hyperactivity

                               Increase physiologic activities

Under secretion – sluggishness

Oestrogen:

-          Promotes evolution of secondary gender activity characters

-          Enhance ovulation together with menstruation

Progesterone: called pregnancy maintenance hormone

Testosterone:

-          Stimulates the evolution of 2^o gender activity characters inwards male

Step     : institute hormones

The major institute hormones include

-          Auxin

-          Gibberellin

-          Cytokinin

-          Abscicic acid

-          Ethylene

Auxin: the most of import auxin is IAA (Indol acetic acid) produced at the apices of shoots

Functions:

-          Promotes growth of shoots roots

-          APICal dormancy

Gibberellin:

-          Induces fruiting

-          Breaks seed dormancy

-          Promotes flowering

Cytokinin:

-          Controls cells division

-          Slows downwardly aging

Abscicic acid:

-          Promotes aging & abscission

Ethylene:

Promotes fruit ripening

Evaluation

1.       State the business office of whatever 3  animal hormones together with whatever three institute hormones

Summary:

Chemical messengers produced yesteryear endocrine glands acquit information from i indicate to another.

Together alongside nervous system, they coordinate activities of the body

Homework.

Suggest ways yesteryear which your noesis of institute hormones tin assist inwards improving agriculture inwards your habitation country.