## Exploring Different Organisms and Their Size

Different organisms are of different sizes. If I take an example of two organisms such as an amoeba, which is a single celled organism and an elephant, which is a multicellular organism I can see that they are obviously of different sizes. [image] amoeba Amoeba [image] elephant Elephant Since an amoeba is small it has a large surface area compared to its volume. Since an elephant is large its surface area is small in comparison with its volume. As can be seen below if one increases the surface area of an object, the total volume increases but the surface area: volume ratio decreases. 3cm [image] 2cm [image] 1cm [image] Total SA= 6 24 54 Total Vol= 1 8 27 SA:Vol= 6:1 3:1 2:1 An amoeba exchanges with the environment by occurring across the entire body surface through the cell membrane. An elephant exchanges with the environment by taking in oxygen into the respiratory tract and carbon dioxide, which is produced by respiration in the body of the elephant is released into the atmosphere. Since an elephant has large flat ears this increases the surface area of an elephant for radiating body heat in hot climates. For an elephant respiratory gases cannot reach its body tissues by only diffusion.

## Geography Essay

What is geography? This is a subject that studies about the surface of the earth together with how people and the environment interact. It can also be about the surface of the earth in terms of topography, landscape and political divisions. In case you would like to write a geography essay, then you know what to include in your topic list. We will help you write this essay by providing you great tips here.

## The Senses of Soul

"What is the most human to us, often, is the most sacred."

## BAROMETER

A barometer is a device for measuring atmospheric pressure.

## The Effect of Surface Area on the Rate of Reaction Between Catalase from a Potato and Hydrogen Peroxide

Aim To find out the relationship between the surface area of a potato chip and the rate of reaction when hydrogen peroxide is put in with it. Variables As I do this experiment the thing I am going to be changing is the surface area of the potato chip, first I will put it in the beaker as a whole (3cm chip) then I will start cutting it into smaller pieces and repeating the experiment. I will keep the temperature the same throughout all the experiments also I will keep the amount and concentration of hydrogen peroxide the same, the amount of potato and the same brand of potato. By doing this I will make it a fair test. Prediction I predict that the bigger the surface area the quicker the 10 cubic cm of hydrogen peroxide gas will be produced. I think this because as the surface area increases, the speed of the reaction will increase therefore the gas will be produced faster. I believe this because most chemical reactions happen faster when there is more of the reactant to react with. When there is a larger surface area, there is more of the reactant available, which makes it easier for them to react together. Usually, when the surface area is doubled it will double the rate of reaction.

## Surface Area of Leaves

Aim: To find a connection between the size(surface area) of the leaf and the distance between the trunk and the road. Hypothesis: Yes, I believe that the surface area of the leaves will increase the further away from the road they are. I believe that there are many reasons all due to different pollutions, caused by the cars driving on the road. I?m sure that it affects the leaves in other ways such as premature leaf drop, delayed maturity, plant growth, reproductionâ??.but also the size will get affected. Cars are responsible for a tremendous amount of air pollution and wasted energy that affect humans and our environment. Acid rain, which is caused by air pollution, poisons our water as well as plants.

## Polar Bear Experiment

olar Bear Experiment Aim === I am going to investigate how the size of a Polar Bear affects its loss of heat. I will be doing this by using beakers with hot water to represent the Polar Bears. ================= Variables ===== There are many factors that determine how quickly or slowly heat is lost. The factors are as follows: amount of water, shape, temperature and surface area to volume ratio, insulation and types of Beaker. I am going to investigate how variations in surface area: volume ratios in beakers lead to variations in heat loss. In order to make a fair test I will need to keep all other variables the same, these variables are amount of water, shape, temperature, insulation and type of beaker. The amount of water will have to be regulated because if I kept the amount of water the same there would not be a variation in mass and so the experiment would not give as clear results so I will be filling the beakers to half their full capacity. Prediction == I predict that in the smallest beaker the heat-loss will be the greatest and in the largest beaker the heat-loss will be the smallest. This is because with the small beaker there are a lot of spaces for the heat to escape from and there is little mass in the middle and so heat is lost quickly. The large beakers have a surface area larger than the small beakers but have a smaller surface area: Mass ratio because they have a very big mass. This means although heat escapes quickly it can not cool the centre of the water as quickly as with the small beaker because it has a larger Surface Area: Mass ratio.

## Pfiesteria

Many states have been plagued with the problem of Pfiesteria,
and until recently the cause was unknown. As the climates and
ecosystems change some organisms favor the change and others do
not. One organism that favors the changes is the dinoflagellates.
This organism creates a toxin that causes deep bleeding soars in
fish. Then the dinoflagellates eat the fish?s exposed flesh and blood.
Pfiesteria also has an effect on humans. It has been found to cause
severe headaches, blurred vision, nausea, difficulty breathing, short-
term memory loss, and cognitive impairment.

## The Reaction Between Marble Chips and Hydrochloric Acid

Using the syringe method I am going to investigate the reaction between
Marble chips and hydrochloric acid by measuring the volume of carbon dioxide
formed.

## Global Warming and the Greenhouse Effect

The greenhouse effect, in environmental science, is a popular term for the effect that certain variable constituents of the Earth?s lower atmosphere have on surface temperatures. It has been known since 1896 that Earth has been warmed by a blanket of gasses (This is called the ?greenhouse effect.?). The gases?water vapor (H2O), carbon dioxide (CO2), and methane (CH4)?keep ground temperatures at a global average of about 15 degrees C (60 degrees F). Without them the average would be below the freezing point of water. The gases have this effect because as incoming solar radiation strikes the surface, the surface gives off infrared radiation, or heat, that the gases trap and keep near ground level. The effect is comparable to the way in which a greenhouse traps heat, hence the term. Environmental scientists are concerned that changes in the variable contents of the atmosphere?particularly changes caused by human activities?could cause the Earth?s surface to warm up to a dangerous degree. Since 1850 there has been a mean rise in global temperature of approximately 1? C (approximately 1.8? F). Even a limited rise in average surface temperature might lead to at least partial melting of the polar icecaps and hence a major rise in sea level, along with other severe environmental disturbances. An example of a runaway greenhouse effect is Earth?s near-twin planetary neighbor Venus. Because of Venus?s thick CO2 atmosphere, the planet?s cloud-covered surface is hot enough to melt lead.