In the Urinary system there are two kidneys, each with their own separate blood supply. Each carrying out the process of excretion and filtration osmoregulation.
From each Kidney there is a tube that leads to the bladder called the Ureter. The ureter carries Urine from the kidney to the common bladder.
Urine is then conducted to the outside of the blood to be excreted down a structure called the Urethra, which either down through the vagina or penis.
Osmoregulation = Osmosis/regulation (control of composition of blood) Tissue flood surrounds cells must be Isotonic with the cytoplasm of the cells. This means that the amount of water going into and out of these cells is equal and the cells shall remain the same size and function.
The danger to the tissue is that blood that is circulating into the tissue would be concentrated causing a hypertonic tissue flood. Or may be very dilute causing a hypotonic tissue flood. Both of these are undesirable. Hypertonic would remove too much water and Hypotonic would add too much water. We want to keep the tissue fluid Isotonic to the cell cytoplasm.
This is achieved my controlling the composition of blood. Blood forms the tissue fluid. It is the role of the kidney to control the composition of blood. Blood which circulates though our kidney excess water + salts can be removed and excreted down the ‘Ureter’.
By controlling the content of water and salts in the blood, the kidney can keep the blood and tissue fluid isotonic with the cell cytoplasm, maintaining the functions of the cells.
Excretion of the molecule known as Urea (contains Nitrogen = toxic to body and cannot be stored)
The original form of nitrogen = Amino Acids (excess). Amino Acids that are in excress must be removed; this is role of the liver and the kidney. Blood circulates to the Liver and Amino acids are broken down and converted into the molecule Urea.
This reenters the blood steam and enters both kidneys. The Kidneys will filter the Urea from the blood and the urea will be added to water to create Urine. The Urine travels down the ‘Ureter’ in the Kidneys to collect in the bladder.
1. Photosynthesis = Leaf absorbing light energy. Combines Carbon dioxide + water ---> molecules (i.e Glucose) + Oxygen. In this case Oxygen is a waste molecule. Oxygen is an example of Excretion.
2. Respiration = Glucose + oxygen ---> ATP + Carbon dioxide + water. The Carbon dioxide is the excretion in this case.
1. The ovary produces Oestrogen which flows through the blood stream to the lining of the uterus. The effect of oestrogen is the thickening of the wall of the endometrium. This occurs during the first day of the cycle to around the thirtieth.
2. The oestrogen then flows from the bloodstream to the brain where it releases another hormone called luteinising hormone. The release of the LH reaches its peak at around day thirteen which causes the ovary to release an egg. This happens because during the first half of the menstrual cycle a circular structure known as a follicle becomes increasingly larger. Inside the follicle is the egg. The cells around the follicle produce the Oestrogen. At around day thirteen the follicle reaches its largest size. When the LH causes the lining around the ovary to rupture and the egg is released. The egg will come out of the ovary and into the oviduct where it becomes possible for fertilisation to occur.
3. The empty follicle changes function. It turns a yellow colour. This is called Corpus Luteum ‘Yellow Body’. The yellow body produces progesterone. Progesterone travels through the blood steam to the lining of the Uterus. The progesterone prevents the lining of the uterus from breaking down. Here, it is possible for the fertilised egg to implant into the wall and develop into a pregnancy.
4. If there is no implantation of a fertilised egg then the corpus Lutuem breaks down and progesterone levels fall. The fall of progesterone levels causes the break down in the lining of the Uterus. This is known as the menstrual period or the menstrual bleeding. Once the lignin had fully broken down then the cycle begins over again.
-The wall of the Uterus is called the Placenta. - When the child is in the uterus, it is full of embryotic fluid - The child cant digest or breath or excrete whilst in the mother. - The placenta grows out of the developing embryo, does not grow out of the mother. - The Blood vessels inside the placenta are the child’s blood vessels (arteries, veins) - Placenta grows into the wall of the uterus. - Glucose amino acids, fats, travel through the bloodstream of the mother and into the wall of the uterus. - The Sugars, amino acids and fats will cross into the child’s blood at the placenta and then taken into the child. - Placenta has a large surface area. -The barrier between the mother’s blood and the child’s blood is very thin.
P (Promphase) = The chromosomes aPpear
M (Metaphase) = The Spindle Fibres join in the Middle
A (Anaphase) = The Spindle fibres pull the 'pair of chromatids' Apart
T (Telophase) = Two new sets of chromosomes are formed at each end of the cell and a nuclei is fromed over each group.
3.24a
Mitosis –form of cell division, which results in growth (growth = increase in number of cells)
The number of chromosomes in a nucleus is known as the Diploid number (2n)
i.e 2n= 46 human 2n=38 cats
During the process of mitosis the cell will divide to become two cells, each with a nucleus. Inside the nucleus they each have a ‘diploid nucleus’, he cells are identical (aka daughter cells)
Identical because they have the same number of chromosome and they also have the same set of chromosomes (a chromosome from one cell will have an identical chromosome in the other cell)
3.24b
How are copies of chromosomes made and how do they separate into the two cells?
The split cells have the same number of chromosomes and same set of chromosomes.
The first cell has to copy its chromosomes to produce another set for the second cells. This process is called DNA replication. In this process each chromosomes undergo a copying process to form an identical copy of itself, with all the same jeans and alias. These two copies are held together around the center region by a structure known as a centromere (“pair of chromatids”)
Takes place in the cell nucleus; this is known as the Interphase of the cell cycle.
3.24c
Stages of Mitosis
During the phase of interphase is when the DNA replication occurs.
The first sign that a cell is entering the process of mitosis is when we see the breakdown of the nuclei membrane, known as the Prophase. The chromosomes become visible as a pair of chromatids.
A network of protein molecules known as the spindle and the spindle fibers extend from one pole of the cell to the other.
Late Prophase: the pair of chromatids will move towards the spindle and will join onto one of the spindle fibers at the centromere.
Metaphase: Chromatids are in the middle arranged across the equator of the cell attached to the spindle fibers connected by the centromere.
Anaphase: the spindle fibers shorten, pulling on chromatid in one direction and the other in the other direction, separated the ‘pair of chromatids’. They move to the poles of the cells
Telophase: The nucleus begins to reform around the chromosomes at the end of the cell. This will be the new nucleus of the new cell.
Cytokinesis: The cell splits into two. This is NOT part of Mitosis (it’s what happens after). The cell moves inwards, dividing the cytoplasm in half and the membrane will fuse across the equator to form the two cells. (In a human 23 pairs of chromosomes are separated).
-Chromosomes: Is composed of a molecule called DNA. DNA forms a shape called the double helix. Sections of the molecule are called genes. One chromosome will have many jeans (possibly 1000).
- Each gene carries the info for the construction for a protein. The protein gives us the characteristic associated with the gene, (i.e blood group)
- Diff organisms have different number of chromosomes (cat 37, chicken 78, chimp 42, human 46)
- Chromosomes are known to operate in pairs, known as homologous pairs. Same Gene, in the same place on each chromosome in homologous pair. Same gene but different version
- Characteristic 2 versions of each. These versions are called Alleles
Sexual reproduction:
Show sex (genders – male/female)
Produce cells called gametes (male=sperm female=egg)
Meiosis- the type of cell division that produces gametes –effect: half the total number of chromosomes in the gamete cell (e.g. chromosomes. Humans: 46 per cell Gametes: 23 per cell, the process from going from 46 to 23 is called Meiosis.
Fertilisation (gametes cells from a male (sperm) fuse together with the gamete cell from a female (egg))
Broad variation (many differences in individuals of population)
Asexual reproduction:
DO NOT show sex (genders – male/female)
No gametes
Mitosis (in eukaryotic cells) /binary fission (in prokaryotic bacterial cells) cell with 20 chromosomes 2 cells (each with 20 chromosomes -identical)
No fertilisation (because no gametes)
Small variation – due to mutation (they are identical ‘clone’)
Quetion: What are eukaryotic cells and prokaryotic bacterial cells?
1.CO2 from Atmosphere. .03 of atmosphere Photosynthesis – reducing the atmosphere CO2
2.Producers eaten by primary consumers. PC takes in the carbon from the producer to put back together its own body materials (grows) Primary Consumers eaten by secondary consumer..etc
3.Each organism carries out the process of respiration. respiration adds CO2to the atmosphere. All organisms are putting carbon into the atmosphere through respiration
4.Death of organisms Organic molecules that remain are broken down by the decomposer organism (bacteria and fungi) results rerelease of CO2 back to atmosphere
5. Fossil fuel (compression and pressure of animals) results in formation of oils and coals. Which are combusted to release co2 e.g. 1. industrial/motor vehicle 2. Naturally: lightning striking vegetation – forest fires and grassland fires.
By Pollution Molecules such as Carbon dioxide, methane and water vapour (greenhouse gasses). These gases will increase the concentration in the upper atmosphere. And the consequences are the infer red light from the planet surface would be readmitted constantly back to the surface (rather than escaping) this cause a raise in the average global temperature = Global warming. Consequences - Malting of ice caps - Raise in sea levels - Ocean currents change - Change the way Wind generated - Distribution of the world’s Biomes (‘Ecosystem’) - Deserts expand
1. Human activities i.e burning of fossil fuels results in the formation of CO2/NO2/ SO2 (greenhouse gasses) They absorb infer red light and they will redistribute it back towards the planet Fossil fuels from factories (industrial) and vehicles and burning of coals (domestic) 2. Farming. –Cows admit ethane gas into atmosphere (Around 9% of greenhouse gasses) 3. Evaporation of water water vapour (Clouds) 4. Refrigeration/ Solvents/ propellants. CFC (Chlorine, Florine, Carbon) i.e CCL3F
Combustion of fossil fuels in factories (ie coals and oils) gives off the gas SO2 Also in vehicle the combustion of oils/petrol/gas also contributes
In atmosphere SO2 +H2O -> sulphuric acid Condenses to form clouds and when it rains we call this acid rain. Acid rain affects plants and animals Trees and plants are often ‘burned’ (tops of trees) Acid rain causes Ca2+ and mag 2+ to be LEACHED out of soil (plant can’t obtain magnesium or calcium in plant which means the plant can’t grow) Effect of acid rain in lakes (enters strems which then form lakes) reduce the pH which releases the Al3+ ions. Which affect the rate of fish deaths. The aluminum causes the thickening of the mucus which lines the sides of the fish’s gills, which reduces the fish ability to take oxygen from water = suffocation (death)
Carbon monoxide (CO)
Fossil fuels (coal/gas) are burned with insufficient oxygen which creates CO Carbon monoxide (CO) combined with the hemoglobin which is formed in the Red Blood cells and forms a molecule called Carbamino hemoglobin (blocks hemoglobin from carrying O2, reduced 02 circulations.) Is Toxic = causes death
Tuesday, 10 May 2011
Using quadrat technique to sample the population of daisies:
Use random sample (so not biased) also must be representative (large – for good results)
- Find random number to find the y and x axis numbers. For example if the random number was (3,3) the data would be taken from quadratic square (3,3)on the field. - Each quadrate in this example is 1m by 1m - Then count the number of daisies in that square
The sample needs to be representative Sample : - The bigger the better - 10 quadrates/ 10% of the actual area would be taken for the results - Collecting data: Make a table. One column called ‘quadrates number’ and other column ‘Number of daisies per meter squared’ Add up column ‘Number of daisies per meter squared’
Divide the total from column ‘Number of daisies per meter squared’ by the number of quadrates The result is the number of daisies per meter 2
Using this data we can compare the population of daisies with other field.
- Sand dune Ecosystem: made up of a number of populations (like all ecosystems) which then form the community and habitat.
- The fence runs through the middle which slits the sand dune area into two regions. One region is ‘Grazed’ by cattle and the other is ‘not grazed’
- Quadrating - (Quadrat = squares) Using string/wood/metal to make a square grid. Usually about 0.25m by 0.25m (or up to 1m by 1m)
- Quadrat used to sample the area and count the number of individuals here. The process is repeated a few times. This is done to get an estimate of the population size.
- Overall, Quadrating are a method or sampling different locations of population can be compared in the two locations.
Thursday, 21 April 2011
- Pollen grain on the stigma and they germinate and tubes begin to grow off them which then enter the ovule. The nucleus moves down the pollen tube to the nucleus - Pollen nucleus will fertilize the ovule leads to formation of the Zygote (grow in the embryotic plant) - Outside of the ovule forms the seed coat called the TESTA - Also inside the Ovule are the Cotyledons which are food stores for the seedlings. This will support the plant until it has developed its first leafs - Thickening of the walls of the ovaries. The plant will put in a lot of energy, things like sugars/proteins. Build up will create fruits (developed in the wall of the ovary/carpel)
-Transfer of the pollen grain for the anther (By air, carried through Wind) to the Stigma - Adaptations: 1. Lightweight pollen grains with some kind of wing feature which allows them to move through the air efficiently 2. Anthers will hang well clear of any basic flower structure, exposed to the wind. 3. Stigma, large surface are, feather like structure to catch the pollen grains as they pass through the air on the wind. - Grass, no colour in the petals and no scent to attract insects. - Waste of energy to produce nectarines since it is a wind pollinated plant.
Wednesday, 6 April 2011
Structure: - Petals - Staman (male part) - Anther (pollen grains), Filament - Carpel (female part) - Stigma, style and Ovary (ovules) - Pollinating Flower: When Pollen grain is transfers from the ANTHER in one plant to the STIGMA in another plant - Pollen is a small stucture that contains male NUCLEI -Flowers attracts inscent Attraction Adaptions from Insects: - Signals: SCENTS AND COLOUR PETALS - Value: POLLEN (source of protein) AND FOOD (nectaries produce fructose)
Phototropism example: The stem of the plant detects the sun light which then bends in the direction of the source.
- Phototropism = light growth towards light - If the light hits the tip of the stem it grows upwards - If the light is coming from the side (lateral light source) then the plant will bend as it grows - Light on only one side will cause the other side to bend - If one side contains the compound Auxin (hormone) then it will bend. This is because it is caused by growth on one side but not on the other.
Geotropic: Geo – Gravity, Tropic – Growth Response Embryotic root growing towards the Stimuli (source) = Positive Geotropism Embryotic root growing Away from the Stimuli (source) = Negative Geotropism If rotated it will change direction to grown to either upwards or downwards
- Stimuli are changed in the environment (i.e. Temperature, Gravity or light chances) - The plant has Receptors which can detect the stimuli - Turn it into a Response, which take the form of Growth (Tropism) - Tropism that involves light is called Phototropism. - Tropism that involved Gravity is called Geotropism - Tropism's might include Mitosis and cell elongation
Tuesday, 22 March 2011
- Evaporation of H20 (liquid to gas) involved heat. The heat is provided by Sunlight as it’s absorbed by the leaf structure through the stomatal pores - Water travels up the plant to the leaf, where sunlight heats up the leaf, providing the heat needed. - Cross Section: Not all light will be absorbed by the chloroplast; some absorbed by other cell structures and will generate heat. - Water enters through Xylem, and moves through the spongy mesophyll. Just above the stomatal pore the change occurs from liquid to gas. - Diffuses through pore at a steep diffusion gradient
Friday, 18 March 2011
A potometer is used to measure the rate of water uptake up a leafy shoot.
