Percentage Error from equiptment used.

*An error is half the smallest possible reading.*

The errors can come from:

• Thermometer: reads to nearest degree celcius, half = +/- 0.5 degrees celcius error.
  
• Balance: Reads to two decimal places, so the error is half of 0.01, therefore, +/-0.005g

Working out errors:
Balance error- We weighed on the balance twice, therefore, times eror by two = 0.01, then:
0.01/mass weighed (calculated). You then multiply this by 100 to get the percentage error.

So:

1. Multiply error by how many times used. (I.e., two readings = multiply by two.)
2. Divide this by the mass weighed, which you should have calculated.
   
3. Multiply by 100 to reach the % error. (:
   

Thermometer Error-

1. Times the error by how many times used read off the thermometer. (So, two, would be 0.5 x 2 = 1) :D
   
2. Then you divide this by the difference in tempereature, which you should have calculated, or been given.
   
3. Multiply by 100 to get the % error.
   

Thereeeyougooo. All done for today, more tomorrow possibly, or friday. (:

Measuring energy changes.

If the energy given out is bigger then the energy put in, it's exothermic, if the energy put in is bigger then the energy given out, it;s endothermic.

q=mc(delta)T

q is the heat/enegry given out in joules.
m is the mass of the substance heated.
delta T is the rise in temperature in celcious or kelvin.
c is the specific heat capacity, usually 4.18 J/g/k

To get from equation to answer in KJmol-1, there are 3 basic steps:
1) Calculate Q from the info given, using q=mc(delta)T
2)Calculate moles of fuel from the mass of fuel burnt.
3) Divide 'q' by the moles to get the answer in joules, and then divide this by 1000 to get the answer in kJ

Insects :D

Key terms:

• Spiracles
• Trachae
• Tracheoles.
  

Some insects will have a high metabolic rate from springing, jumping, flying, etc. Need a lot of food for respiration to provide ATP for muscle contraction, in which case, they wouldwould need oxygen and some sort of system.

They are small, and therefore have a large SA/V ratio.

Exoskelton- skeleton on the outside. Hard, rigid and waxxy. Subject to dehydration,exo skeleton is waterproff to prevent this, and therefore, gases cannot be exchanged through the surface.

Tracheal System:

---------
| head |----------|-----------------)
---------| thorax |____abdomen_)
|_______|

Okay, yeah. I just drew a diagram of bug anatomy with my keyboard. Swish, eh?

Anywhoz...

Air enters the insect's body through valve like openings (spiracles) in the exoskeleton. These are located laterally along the thorax and abdomen of most insects.
Air flow is regulated by small muscles that operate one of two flap like valves within each spiracle -contracting to close the spiracle, or relaxing to open it.

Trachae are tubes that carry air directly to cells for gas exchange. They penetrate between cells and muscle fibres. After passing through a spiracle, air enters a longitudial tracheal trunk, eventually diffusing throughout a complex branching network of trachael tubes that divide smaller and smaller to recah every part of it's body.
At the end of each trachael branch, a specialised cell (tracheole) provides a thin, moist surface for the exchange of gases between atospheric air and a living cells.
Oxygen in the tracheal tube frist dissolves in the liquid of the tracheole and then diffuses into the cytoplasmof an adjacent cell. At the same time, carbon dioxide, produced as a waste product of cellular respiration, diffuses out of the cell and eventually out of the body through the tracheal system.

The muscle contracts using ATP from aerobic respiration, and then uses anerobic respiration, which produces lactic aicd, which is soluble in water, this lowers the water pressure in the muscle, and water then moves in by osmosis from the tracheole. Since the oxygen is dissolved, this makes a faster rate of movement of oxygen to muscles.

-Thoughts?

Nin. (:

SA/V ratio and temperatures. :D

What causes the higher body temperature of birds?
A high metabolic rate, so, when glucose is broken down, some is converted into heat energy, which maintains heat.

What is the relationship between bodymass and time spent feeding?
The greater the amount of time spent feeding, the lower the body mass, as, as the body mass increases the surface area to volume ratio decreases, therefore, there is less surface area to unit of body volume to loose heat through, so the rate of heat loss is slower, and hterefore, less energy is needed to maintain body temperatures (and also, food.)

Low raio of SA/V helps maintain a body temperature:
Large volume mean there are lots of cells repiring and producing heat energy. Also, surface area is relative to volume, and if it is very small there is less for heat to escape from, so rate of heat loss is slower.

How does the given trend: 'The greater body mass and length, relies on a higher latitude, and lower winter temperature', explain how possums adapt to where they live:
An increase in size means a reduction in SA/V ratio, meaning the area through which heat can be lost can be reduced, compared with the size of the posum. The conserves heat, and lowers the amount of energy required to maintain body temperature.

Suggest a reason for no adaptation in size in cooler climates:
SA/V is only one thing that can be adapted, other things like insulating fur can make a difference. As can higher metabolic rates, as more energy could be generated to compesate for heat loss. There are also behavioural habits like migrating and hibernating that could affect it.

(: That's alllll... :D

Fish and Counter Current Flow and that. (:

I have a feeling I've missed a little from what we studied, so I'll find my old notebook later and get it from there, but alas, fish: :P

Counter-current flow = Constant concentration gradient.

The water, and the blood in the blood vessels are flowing in opposite directions. Oxygen diffueses from the water into the blood, which causes the oxygen concentration in the water to fall. The concentration of oxygen in the blood, subsequently, rises. However, concentration of oxygen in water is always higher then in blood, therefore, a constant concentration gradient is maintained.

In the gills, the flow of water is in the opposite direction to the flow of blood, therefore, the concentration gradient is maintained. This means the blood is continually meeting fresh water with a higher percentage concentration of oxygen.
The concentration gradient is maintained across the gill lamellae and oxygen continues to diffuse into the blood. The same would not happen if they flowed in the same direction, as diffusion would only occur until equilibrium is reached, which is less effcient.
When in counter current flow, 90% of the oxygen the water contains if difused, whereas if it was parallel flow, only 70% would.


Thoughts?
-Nin.

How Do Alkanes React?

Alkanes are less reactive then alkenes. (All single bonds.)

There are four electrons in the area between the two carbons, which is called an area of high electron density.

To make a double bond, you have to distort orbitals, which means, the bond is strained, and would prefer to like, 'burst out', as such, and form single bonds.

Double bonds attack things, as they are really really unstable.

Breaking double bonds - Addition Reaction.

Electrophyllic = The electron loving one, positive
Nucleophyllic= The nucleus loving one, negative.

When drawing the examplesof electrophyllic addtion reactions always:

Draw the molecules being polar.

Include ALL arrows. To the right place.

Include the second structure. (With the positive carbon.)

Show the final product.

Isomer:

• Structural
  - Chain (alter the carbon chain) -Positional (move functional group.) -Function (functional group changes.)
• Stereoisomers.
  -Geometric (E/Z)

Thoughts? Remember, correct me if I'm wrong. I'm only an AS student myself. (:

-Nin.

Chem: Geometric isomers and that. (:

Electronslive in orbitals. When an S and P orbitaljoin together, that makes a single bond.

Stereo Isomerism requires a double bond, and each carbon either side of it, to have two different things on it.

This type of stereo isomerismis known as geometric isomerism.

The two geometric isomer types are 'E', and 'Z'.

E/Z goes by molecular mass of things attached.

Z= The highest priority atoms/molecules TOGETHER.
E= The highest priority atoms/molecules OPPOSITE.

By highest priority, I mean highest mass.

So, a Z (together), would be, for e.g.:
H- -H
C=C
Cl- -Cl

(the '-' means a diagonal bondto the C, not a -ive ion.)
This would be because on both C's, the Cl has the biggest mass, and is therefore of priority, and they are both together on the same side.

An E would be:
Cl- -H
C=C
H- -Cl

Because, once again, the Cl is of greater mass on both Carbon, and they are therefore, of priority,andthey are at diagonals.

Instructions/Checklist for recognising Geometric Isomers:

1. Double Bond?
2. Does each carbon have two different things on it?
3. Which has the bigger mass on either side?
4. Are these together or opposite?

-Nin

More Chloroplast stufff. :D

Chloroplast envelope- a highly selective double membrane.

Grana- Stacks of about 100 disk like structures called thylakoids. Thylakoids contain Chlorophyll (the photosynthetic pigment.) Grana are linked by lamellae, (pieces of thylakoid membrane). The first stage of photosynthesis takes place on the grana.

Stroma- is the fluid filled matrix where the second stage of photosynthesis takes place.Contains lots of enzymes.

Chloroplasts contain ribosomes and DNA to manufacture the proteins needed for photosynthesis.

DNA contains genetic code.

CO2 and Water go in via the membrane, oxygen and glucose go out.

Plant Cell Wall:
Cellulose- makes molecules bonded to form micro fibrils,which stack and form cell wall. Cellulose is a polysaccharide made from Beta Glucose.

Many micro fibrils make a fibril.

Cell Wall:

• Consists of microfibrils of the polysaccharide CELLULOSE in a matrix.
• They are very strong.
• They give the wall mechanical strength, and prevent it form bursting due to osmotic pressures.
• This allows water to pass along it.
• The middle lamella (thin layer) marks the boundary between the cell walls.

Cellulose: Straight polysaccharide chains of Beta Glucose. The chains hydrogen bond together, forming very strong fibres. They are insouble. Use: Supports andstrengthens plant cell.

Insoluble, important as: won't affect water potnetial.

Amylopectin: Alpha glucose helix with branches. The branches give more end points for hydrolysis to take place, and therefore, it is broken down quicker.

Glycogen: A carbohydrate foundin animals. (AN: Yeaaaa!Found it.xD!) It is alpha glucose, and therefore forms a helix. It has more branches, and these branches have side branches. This means thereare even more points for Hydrolysis,andisit broken down even quicker, as Amylopectin is in plants, and they don't do as much, but Glycogen is in animals, which are far more active, and therefore, it needs to be broken down quicker.

More notes from before exam.

Water Soluble = Polar molecule, therefore, cannot pass through phospholipid bilayer. Goes through protein channelsas they have hydrophyllic linings.

Lipid Soluble = Non Polar, /will/ pass through (directly) the phospholipid bilayer.

Boiling an enzyme will denature it, therefore, it looses it's tertiary shape, and cannot function. The substrate will not be hydrolysed.

What would happen to need a coronary by-pass thingy:

1. Atheroma would form (fatty, cholesterol build up in lungs.)
2. This would be on the lining/epithelium/lumenof the coronary artery (all good words to use, those.)
3. This reduces/obstructs the blood-flow.

Higher salt intake= Higher BP, because... Ion intake (Na+,Cl-) increases, therefore, water potnetial is lower, and water then moves into the blood, increasing it's volume, andtherefore, proportionally, the pressure increases.

Three components of a triglyceride = Three fatty acids and a glycerol molecule. In a condensation reaction. This is opposite to Hydrolysis.

Disulphide bond- strong, covalent bond between two sulhpur atoms.

The Alpha Helix, and the Beta Pleated Sheet are held together by hydrogen bonds.

When speaking about variables, don't use the word 'amount', but specify, so: Temperature, Volume, pH, Concentration, or even Age.

Don't use the word 'size', use 'volume'.

Glycogen is a storage carbohydrate. I think it is in animals,not 100% sure. Will check andpost later. (:

Carbon dioxide is not produce as quick with lactose as with glucose, as glucose can be used immediatley, whereas an enzyme must be synthesised for lactose.

Scar tissue reduces the surface area for gas exchange through damage.

'Human Error' is generally too vague a statement.

Litigation = Sueing the company.

Why antibodies are much faster when the same antigen enters the body on a second occasion:

• Memory cells are produced during first respone/exposure.
• Memory cells recgonise the antigen immediatley, and develop into plasma cells.
• This is by cloning.
• Quicker response, as the production of plasma cells is quicker.
• More plasma cells, therefore, more antibodies, = more chance of colliding with, combining with pathogen.

Myocardial Infarction = Heart muscle dying.

That's all, folks :D

-Nin. ^_^

Odd Notes from end of early January.

A control group allows you to make valid comparison of the results.

B Lymphocytes respond to specific antigen, divide rapidly and produce clones. Some of the clones form plasma cells, which secrete antibodies. Some of them form memory cells, which become active on the second exposure to the same antigen, and this means they produce the antibodies faster, and in larger quantities.

-Nin. (: