2.75 Urine

-urine contains water, urea and salt

- the brain influences the functioning of the 2 kidneys

- and how the 2 kidneys are filtering our blood

- the molecules which are removed which come down the ureter collect in the bladder and together this form urine

-the salt and water effects the composition of tissue fluid [ osmoregulation]

- the removal of urea is part of the process of the excretion of metabollic waste

-composition of urine: salt, water and urea

--> varies and depends on the condition which a person is operating

2.74 Anti-diuretic hormone.

-ADH- anti diuretic hormone

- ADH is produce in a region of the brain known as  the hypothalamus, flows through the bloodstream and its target is the kidney (flow through like all hormones)

- the effect of ADH is to control and alter the composition or the quantity of water in the blood

-ADH has the ability to make the blood more or less concentrated- the tissue fluid is isotonic to the cytoplasm of the cell [role of ADH]

-ADH targets the collecting duct

- the effect of ADH is that it allows more water to come out of the collecting duct

- the collecting duct is responsible for the water to be selectively reabsorbed into the blood

-possible to increase the amount of water going into the blood by applying the ADH in 

- ADH makes the collecting duct wall more pores

--> more water can escape from the collecting duct and the water can go back into the blood

- the consequence of ADH secretion is that the urine coming from the nephron would be more concentrated and would have a lower volume, the urine becomes more concentrated

2.73 Glucose Reabsorption

-selective: the molecules is selected (glucose)

-reabsorption: go from the glomerula filtrate and it will go back into the blood, removing the molecule to the blood but put it back

-filtration occurs in the bowmans capsule- containing glucose, water salt and urea

-water is removed back into the bloof in the collecting duct

- at the end of the nephron the urine is coming out,

urine does not contain glucose, 

- if test urine for glucose and receive a positive test it means that have a condition called diabetes

-[normally no glucose in urine]

-However in the start there is glucose in the fluid, this is because in the proximal convoluted tubule (first section) glucose is removed and is taken back into blood, glucose is selectively reabsorbed into the blood in the proximal convoluted tubule.

-proximal= first, convoluted= twisted, tubule=tube

2.72 Water Re-absorption.

- the bowmans capsule (BC) - location of ultralfiltration

- the blood coming into the kidney (under high pressure) the dissolve content of the blood are forced into the bowmans capsule tube, (glumerula filtrate- containing glucose, water, salts and urea)

- when the filtration occurs it will filter out too much water and as the filtrate passes along the tubal and when it reaches the collecting duct, water is removed from the filtrate and the water is return back to the blood vessel/stream

- water has been selected and has been reabsorbed into the blood

-selected reabsorption of water occurring into the collecting duct

2.71 Ultrafiltration

nephron of the kidney- structure which carries out the filtration of our blood

resulting in two things:

- filtered blood (clean blood) with waste product

-urine (largely composed of water, salt ,NACL, MGCL), urea (nitrogen waste of the body very toxic)

bowmans capsule- filtration process begin (ultrafiltration), filtration of molecules

-the filtration of blood begins with bloof arriving in the kidney, in the nephron entering the afferent arteriole (blood enter), high pressure

- the blood vessel coming out has a smaller and narrower bloog vessel

- the blood vessels pressure increases in the glomerulus

- the high pressure forces the liquid within the blood (plasma- containing water, salts, amino acids, glucose, urea) forcing it outside the bowmans capsule

- when the plasma is forced in to the bowmans capsule, its called filtrate, and since its in the glomerulus its called the glomerulus filtrate

- the blood has been filtered by pressure due to the smaller restricted diameter of the blood vessel [efferent arteriole] generating a the pressure to be high

2.70 Nephron Structure

nephron- this is the functional unit of the kidney- part that does the filtration and the controlling of the composition of blood

-aorta- the branch is taking blood into the kidney is the renal artery

- the kidney filters the blood and the content which is remove from the blood are called the urine, which comes down through the ureter which is collected from the bladder for release

- the filtered blood exits in the renal vein and returns to the rena cava

(see in diagram for the colour)

- the reason for the different colour, is because the kidney is made out of millions of tubes and this will make it easier to see

- the dead end struction is called the bowmans capsule

- the tube is made out of twisted section 

= known as the convoluted tubules

- a collecting duct is just a tube

- the first twisted section is known as the proximal covoluted tubules (PCT)

- the second twisted section is known as the distal convoluted tubules (DCT)

- the arrangement of the nephron structure which gives out the different colour region in the kidney

- there are millions of nephron in a single kidney 

2.69 Urinary system

Kidneys- 2 kidneys, [right and left] - each having its own blood supply, carrying out the role and process of excretion, filtration and osmoregulation

- from each kidney there is a tube which leads to the bladder called the ureter [carry urine from the kidney to the bladder]

- common bladder for both ureters

= urine is conducted from the outside of the blody through the urethra down through either the vagina or penis

http://www.infovisual.info/03/058_en.html [good website] 

2.68 Osmoregulation [Part B]

osmo: osmosis

regulation: to control

- the fluid that surrounds the cell, must be isotonic with the cytoplasm of the cells

- this means that the amount of the water going into and out to the cells is equal 

-the cell will remain the same size shape and maintain the function

the danger to the tissue is that blood circulating into the tissue would be concentrated causing a hypotonic tissue fluid or it may be very dilute causing a hypotonic tissue fluid

-(hypotonic tissue-may remove too much water or add too much water)

- we want to keep the tissue fluid isotonic to the cell cytoplasm

= achieve by controlling the composition of blood

- blood forms the tissue fluid

--> role of kidney to control the composition of blood

- the blood which circulate through our kidney excess water, salt and can be remove and excreted to the ureter

= controlling the water and salt in the blood the kidney can keep the blood and the tissue fluid isotonic with the cells cytoplasm maintaining the 

 of the cells 

2.68 excretion [part A]

- the excretion of the molecule urea (contains nitrogen, toxic to the body and cannot be stored)

- the original form of nitrogen circulation in our blood stream and potentially toxic are the amino acid, used for growth but extra amino acids must be remove

- role of the liver and kidney

- first stage blood circulate to the liver where amino acid are broken down and converted into the molecule (urea)

- re-enter the blood stream and to be removed from the body, circulates to the kidney

-kidney will filter the urea from the blood

- urea + water= urine

-collected in the bladder = in form of urine

- the filtered blood returns to the circulation in the veins with amino acid (toxic) and urea is removed

= example of excretion

2.67 Human organs of Excretion [part b]

LUNGS: - the lungs (first organ of excretion)

- excrete carbon dioxide, waste of respiration

KIDNEYS- excretion of excess water (urea-nitrogen waste from amino acids) and salts

SKINS:- known to excrete water like salt

- sweating

-urea (not very much)

- mostly water and salt (sweat)

2.67 Excretion in plants [part a]

-photosynthesis- leaf absorbing light energy, combines and water to form glucose and oxygen  + excretion

-respiration - glucose and oxygen (aerobic respiration) through an enzyme reaction, glucose molecules are broken down and produce ATP and CO2 and H20

plants excrete oxygen and carbon dioxide depending on whether they are going through the process of photosynthesis pr respiration

3.31 Evolution

evolution: - change in the form of organism (the new form of organism arriving)

- a change in the frequency of alleles

natural selection: - the mechanism of evolution and was first proposed by Charles Darwin

S.A - Causes skin infection and lung infection 

Evolving S.A

1st graph:

- the normal form of SA is susceptible to being killed by methecilline (antibiotic)

- it kills SA

-MSSA

2nd graph:

-random mutation

- break down methecilline 

-resistant form

-MRSA

2 form of bacteria (MSSA, MRSA)

- when antibiotic are applied to the population, MSSA is decreased and MRSA is increased (because resistant to antibiotic)

- increase in frequency of allele for resistant

2 features:

-random mutation - produce the MRSA form

-non-random selection - MRSA survive, MSSA to be killed

=natural selection

3.33 Antibiotic Resistance

-Staphlococcus aureus- cause skin infection and lung infection

-if they are infected by staphlococcus aureus they could be treated with methicilline (type of antibiotic)

- this chemical kills the staph.

-MSSA- methicilline susceptible staphlococcus aureus

- there was a random mutation to the genal of staph. and when the antibiotic (methicilline) was applied the bacteria did not die, given the name of resistant form

-MRSA methicilline resistant staphlococcus aureus

- the mutation has created genes in staph which breaks down the antibiotic and it resists the antibiotic which cause bacteria not to die 

- as the antibiotic is used over time the form of bacteria increasingly survives and becomes more common and this is a serious problem in hospitals and the treatment of people with wounds because the antibiotic no longer work. 

3.32 Types of Mutation

-gene--------(mutation)-----> New alleles

= could have an impact of either being beneficial, harmful, neutral effect.

beneficial= enzyme

harmful= non functional enzyme

neutral= no particular effect, although the neutrality may not last forever, and could either become harmful or beneficial. 

3.30 Mutation

- form of the gene is called the ALLELE

- a certain process can change the base of the sequence, this create a new version of the allele

--> result in production of different protein and phenotype

-different allele exist because of mutation which changes the base sequence of  the gene

3.29 Species Variation

VARIATION= differences in the phenotypes of individuals

--> count/measure to show the differences and how them in graphic form

- individual has a phenotype= because of genotype and the environment

- variation in the population is the variation of all individuals

-Vpop= Vgenotype + Venvironment

= surviving and living in different environments.

1- different classes or groups- variation in population, due to variation in the genotype ( environment not playing a role)

blood groups: A, AB, O, B

2- variation in population and variation in the species are cause by genetic variation (Variation in genotype) these group are modified by the environment forming a smooth curve

e.g.= height in humans- quality of diet

3- variation in population/ species

= phenotypic variation is entirely due to environmental variation

- genes have no role play in the differences that we see in the variation

e.g. home language

3.21 Genetic Probabilities [Part B]

3.21 Genetic Probabilities [Part A]

3.20 a+b

Pedigree Diagrams