2.75 Urine

Urine - Water, Salts,Urea

The amount of salt + H2O affects the composition of tissue fluid.

The removal of urea is part of the process of excretion of metabolic waste

The composition of urine depends on the conditions of which a person is operating.

2.74 ADH

ADH - Anti Diurectic Hormone

Produced in the Brain (specifically the hypothalamus area) and through the blood stream it gets carried to the Kidney.

ADH - control or alters the quantity of water in the blood

The collecting Duct - part of the Nephron. Where the ADH works

It is possible to incease the amount of water re-absrobed back into the blood, by applying ADH.

ADH makes the collecting ducts walls more porous so that more water can escape.

As a consequence: urine is more concentrated and in lower volume 

Summary: With ADH secretion, more water goes back into the blood, but urine becomes more concentrated with lower volume as well

2.73 Glucose Re-absorbtion

Selected Re-absorbtion - the glucose is taken from the Glomerula filtrate and sent back into the blood

In the Proximal Convoluted Tubule, the Glucose in the Glomerula Filtrate is re-absrobed into the blood, as normally there  would be no glucose in Urine

2.71 Water re-absorbtion

The Glomera Filtrate (glucose, H20, salts and urea) in the Bowmans Capsule makes its way to the collecting ducts.

Water is re-absorbed into the blood in the collecting duct.

                               "Water re-absorbtion occurs in the collecting duct"

Question: is it high pressure in the nephron that makes the glomera filtrate move on to the collecting duct?
Yes. Fluid entering the BC is in pressure. 

2.71 Ultrafiltration

Ultrafiltration - the filtration of molecules

The nephron - filtration of blood (into filtered blood + urea < Separate things)

The Bowmans capsule 

(where filtration begins)

               

The high pressure caused by the different sized tubes, forces the plasma (water, salts, amino acids, glucose and urea) out of the blood vessel and into the bowmans capsule 

2.70 Nephron Strucutre

Nephron - structural part of the kidney that does the filtration and controlling of composition of blood

The kidney is made up of millions of tubular structures (tubes) called Nephrons

The nephron as a closer look: 

There are millions of such nephrons in the kidney.

2.69 Urinary System

2.68b Osmoregulation

Osmoregulation : osmosis + control

By controlling the salt and water in the blood the Kidney can keep the blood isotonic (optimum) with the cells cytoplasm, therefore maintaining function of the cells. 

2.68a Excretion

The kidney (and liver) and the excretion of Urea (carries potentially toxic hydrogen)

(the filtered blood - free of urea - travels back)

2.67b Human Organs of Excretion

1. Lung
 - carbon dioxide (from respiration)

2. Kidney
- Water
- Urea (amino acids)
- Salts

3. Skin
- Through sweat : water, salts
- Small amount of Urea

3.67a Excretion in Plants

1. Photosynthesis


carbon dioxide + water ---> glucose + oxygen

- oxygen is a waste molecule and therefore excreted


2. Respiration


glucose + oxygen ---> ATP + carbon dioxide + water

- Carbon dioxide in a waste molecule and therefore excreted

3.34 Causes of Mutation

1. Radiation e.g x-rays

                          sunshine (UV Rays )   > skin cancer

2. Chemicals e.g Tars (tobacco)  > cancer

     Chemicals which cause mutations are called, Mutages. 

     Chemicals that cause cancer are called Carcinogens. 

3.33 Antibiotic Resistance

As the resistant from increasingly survives over time, it becomes more common

Meaning the antibiotic no longer works 

3.2 Types of Mutation

3.31 Evolution

Evolution : change in the form of organisms (new forms)
                 : change in the frequency (number) of alleles
                 : increase in the frequency of the alleles for resistance

Natural Selection : Mechanism of evolution

3.30 Mutation

The change (mutation) creates a new version of the allele

Can affect: phenotype, production of protein

Mutation, changes base sequence  

3.29 Species Variation

Variation = see-able differences in phenotype

Individual Phenotype = Genotype + Environment
Vpop = Vgeno + Venvironment

1. Vpop = Vgeno (no environmental impact)
    e.g bloodgroup

2. Vpop = Vgeno + Vpop
     e.g height

3. Vpop = Venvironment (no genotypic influence)
     e.g home language

3.21b Genetic Probabilities

3.21a Genetic Probabilities

3.20b Pedigree Diagrams B

3.20a Pedigree Diagrams

3.18c Codominance

3.18b Genotypes

3.18a Phenotypes

3.2 Fertilisation

The Process - 
Male diploid cell (2n, 46 complete set of chromosomes) >   meiosis    >  produces sperm, half set of chromosomes/ haploid (n = 23)

Female diploid cell (2n)  >  meiosis  > produces egg, haploid (n)



Fertilization - 
egg cell + sperm cell  ( n+n = 2n   23+23 = 46 )   >

zygote   ( 1/2 male and 1/2 female chromosomes)     >

The zygote doubles (mitosis) over and over again till it forms the embryo

Fertilization > Zygote > Embryo 

3.9b Female Reproductive System

Ovary -  meiosis (production of eggs)
Oviducts - carries egg to the uterus / place of fertilization
Uterus Wall - contracts during pregnancy (muscle)
Lining of Uterus - egg > embryo > child / place of placenta
Uterus Space - where babies develop
Cervix - entrance to uterus
Vagina - entrance for sperm cells ( > Uterus)

3.9a Male Reproductive System

Bladder - stores urine
Testis - Meiosis (produces gamete - sperm cells)
Epidiymis - stores sperm cells
Vasdeferens - carries sperm cells (walls contract) to the penis
Prostate - 20/30% producer of semen (sugars/alkali's)
Seminal Vesicles - 70% producers of semen

Urethra - carries semen to the penis
                 carries urine to its 'exit'
Penis -  carries semen into vagina during sexual intercourse

3.12 Amniotic Fluid

- primarily composed of water

Protects the developing fetus
- fluid cannot be compressed
- absorbs the force of any blow or impact (to the outside wall of the uterus.)

3.11 Placenta

- located on one side of the uterus wall
- a water filled environment, amniotic fluids

- grows out of the developing fetus (the placenta's blood vessels are the child's blood vessels)

- the mothers blood stream (glucose, amino acids - through digestion) travel through the wall of the uterus and into the child via the placenta

- has a large surface area & thin walls

3.24c Mitosis

Interphase - DNA replication process inside Nucleus

interphase
- nucleus breaks down
- visible pair of chromatids

late prophase
- spindle fibers (protein molecules)
- range from one pole of cell to the other

metaphase
- chromatids attach to the fiber by the central near

anaphase
- fibre shorten pulling chromatids apart
- move to opposite poles of cell
- separation of chromatid pair

telophase
- nucleus reforms around chromosomes at either end of cell

cytokinesis
- cell splits into two
- each cell contain identical chromosomes

3.24b Mitosis

- Original Cell duplicates it's chromosomes  --> DNA Replication
- produces two identical cells








DNA Replication


- the centromere holds the pair together

- reffered to as a pair of chromatids

- replication takes place inside the nucleus
  - interphase

3.24a Mitosis

Mitosis = Cell division --> growth

Chromosomes (in nucleus) - Diploid Number (e.g Humans = 46)

The cell halves itself to produce two identical cells

- same number of chromosomes

- same set of chromosomes

3.16 DNA and Genetic Information

1 Chromosome - 1000 Genes                                

      Double Helix - Parallel Lines

4 Base Types  -  Adenine   A

                           Thymine   T                           

                           Cytosine   C                                         

                           Guanine   G  

Bases hold the backbone together by pairing of 

A - T    G - C                                 = base pairs                                              

The order of the bases = gene

http://www.youtube.com/watch?v=CEBmnfLWDQs&feature=mfu_in_order&list=UL

3.15 Genes

DNA - one section = one Gene


1 Gene carries a type of characteristic associated with the gene e.g blood group, petal colour


Nucleus --> Chromosome  --> DNA  --> Gene

Information Flow

Gene (nucleus)  ------>    Protein (cytoplasm)

3.14 Chromosomes

1. Chromosomes have DNA

Sections of the DNA are called Genes


Each Gene carries the information for the construction of a protein - gives characteristic e.g blood group




2. Different Organisms have different amounts of Chromosomes, e.g Humans have 45




3. They operate in pairs - Homologous Pairs

4. The same position/loci on the pair has the same gene (seperate versions for one characteristic)

3.1 Sexual and Asexual Reproduction

1. Organisms with sexual reproduction show gender (male/female)
    Asexual have none


2. Sexually Reproducing organisms have Gametes (Sperm - Male, Egg - Female)
    Asexual have none

3. Meiosis produces the Gametes
    Asexual use Mitosis

3. Sexual Reproduction use fertilization
    Asexual none

4. In Sexually Reproduced there is a broad variation of differences
    Asexual reproduction they are identical (clones)

8.30 Stages of the Carbon Cycle

1. Photosynthesis       Co2 + H2O --> C6H12O1 + O2
 reduces atmospheric CO2

2. Feeding                  Producer --> Primary Consumer --> Secondary Consumer

The primary consumer takes in the carbon from the producer and uses it to grow, the carbon passes along the food chain

3. Respiration             C6H12O6 --> Energy + CO2
 Adds CO2 to the atmosphere by animals

4. Decomposition
After death, the organic molecules that remain are broken down by the decomposer organisms (bacteria, funghi) results in release of CO2 back into the atmosphere

5. Combustion        

Fossil Fuels
Release CO2  (Industrial combustion/vehicles)
              
Lighting striking vegetation/forest or grassland fires release CO2

http://www.physicalgeography.net/fundamentals/images/carboncycle.jpg

4.14 Enhanced Greenhouse Effect

Pollution by increase of

• CO2
• Methane
• Water Vapor 

Increase concentration in Upper Atmosphere

Infrared Light will be increasingly re-emited backwards towards surface (rather than escape into space)

This raises average Global Temperature (Global Warming)

Consequences

• Melting of Ice Caps 
• Raised Water level
• Changes Ocean Currents
• Climate Change
• Changes in distribution of World's Biomes (e.g Desserts expand()

4.13 Greenhouse Gasses

Burning of Fossil Fuels 

• Factories
• Cars/Vehicles
• Domestic 

creates more

• Carbon Dioxide   - CO2
• Nitrous Dioxide   - NO2
• These absorb and distribute Infrared Light back to surface of the Earth

Farming

• Cows emit Methane (9% of Atmospheric Gasses)

Evaporation of Water

• Forms Water Vapor

Refrigeration / Solvents / CFC's

4.12 Greenhouse Effect

"Warming that results when Solar Radiation is trapped by the atmosphere;caused by atmospheric gasses that allow sunlight to pass through but absorb heat energy that is radiated back from the warmed surface of the earth"

• UV Light comes from the Sun
• 50% of UV Light is refracted
• UV Light is converted to Infrared and absorbed  
• Infrared gets emitted back out
• The more Greenhouse Gasses (Water Vapor, CO2) the more heat is trapped 

4.11 Gas Pollution

Sulphur Dioxide - SO2


Comes From

• from the combustion of Fossil Fuels in factories
• Also from vehicles (combustion of oils and gas)

Affects

• Combines with Water Vapor to form Sulphuric Acid       -       Acid Rain
• Acid Rain affects plants and animals (Trees/Plants are often burdened, Sulphuric Acid causes Calcium and Magnesium to be leached out of the soil hindering growth)
• Acidic Rain in water affects pH, causes Mucus to thicken around a Fish's gills, suffocating them

Carbon Monoxide

Comes from

• When fossil fuels (Coal/Gas) are burdened with insufficient oxygen

Effects

• Combines with Haemoglobin in Red Blood Cells to form Carbamino Haemoglobin
• Blocks the Haemoglobin from carrying oxygen - reducing oxygen circulation

4.7 Energy Efficiency

Explain why only 10% of energy is transferred from on trophic level.


PRODUCER  ->  PRIMARY Con  ->  SECONDARY Con  -> TERTIARY Con
100 KJ


         ^
eaten by animal

1. Energy Loss by Respiration
2. Animal can't digest all material of plant/animal (undigested / waste)

4.6 Energy and Substances in Food

4.5b Food Webs

Food Webs of the Ecosystem:
describes the feeding interaction of a community


Shows organisms feeding at different trophic levels:

1. organisms can have multiple trophic levels
2. multiple prey
3. everything becomes linked

here, animals can both be secondary + primary consumers

4.5a Food Chains

Food Chain Links:

PRODUCER  ->  PRIMARY CONSUMER   -> SECONDARY Con    -> TERTIARY Con


1 Organism per Trophic Level
The Chain shows the flow of matter + energy

                       

4.4 Trophic Levels

4.5 Quadrat Samples

The samples must be random - no biased produced
                     has to be representative - large

- set up a grid system across the area
- place the quadrat into a square, using random numbers of the X,Y coordinates
- count the number of variables in that section

Representative sample - bigger the better
                                     - 10 Quadrats / 10%


Data

4.2 Quadrats

Quadrating - made of string / metal / wood

                    - used to sample an area, count the number of organisms in the square 

"The method of sampling different location so populations can be compared"

4.1 Ecosystems

Ecosystem - a community of Organisms
                   - habitat (abiotic factors, non living)


Abiotic Features:

1. Daylight
2. Temperature
3. Rainfall
4. Humidity
5. Slope

Community of Organisms:

Population of different species + their interactions

population - number of individuals of a particular species

species - organisms reproduce fertile offspring

interact - feeding

3.4 Seed and Fruit Formation

- the pollen that lands on the stigma grows a pollen tube down to the ovules
- the pollen (male nucleus) travels down the tube to join with an ovule

Formations
1. Pollen nucleus fertilises with the ovule
    --> forms Zygote/Embryo

2. Outside of ovule forms a seed coat

3. Cotyledons form - food source of seedling

4. Thickening of ovary --> fruit  (sugar + protein)