Bio-Teen December. 2013 | Page 3

2.

What is

Biology?

Biology is

the

study of

living things.

Science is meant to study nature, make reasons for it and create useful predictions. A hypothesis is a possible reason for a set of observations, and it is made to be tested. Theories are hypotheses that are believed to be true until proven otherwise. Biology is the study of life. All living things share characteristics, and can be studied from different levels of organization. To make sure all measurements and data is the same scientist use the metric system. In order to study things too small for the naked eye scientist use microscopes.

The purpose of science is to explain the things that happen in our world and help make it better. Scientist observe and collect data. There are two type of observations, quantitative, which deals with numbers, and qualitative, which involve characteristics that can't be easily measured or counted. Any information collected is called data, which lead to inferences. Inferences and hypotheses are both educated guesses from experiments and prior knowledge.

Hypotheses are usually tested through controlled experiments. Hypotheses are made to be tested, they are useful even if wrong, and can be revised. They can come from prior knowledge, logical inferences and imaginative guesses. Hypotheses help in the search for the basic laws of the universe, that scientists assume are real. Scientist also think that anything can be discovered through questions, which is why the best of scientist are curious and open-minded.

It was once common knowledge that mice came from grains and maggots from meat. Spontaneous generation was the belief that living things could come from non-living things. The first person to try and disprove spontaneous generation was an Italian physician named Francesco Redi. He made a controlled experiment based on his hypothesis that maggots did not come from meat. In a controlled experiment only one variable is changed at a time, that is called the independent variable, the rest, that are kept unchanged and controlled, are the dependant variables. Though many people doubted Redi’s findings, they supported his hypothesis, and lead several other scientist to test spontaneous generation. Lots of scientist retested the same experiments to reproduce results, because scientist believe nature is consistent. Anton van Leeuwenhoek discovered animalcules at around the same time as Redi’s experiments. When looking through a microscope he found tiny living things, no one knew how or where they had come from.

The scientist that finally put to rest spontaneous generation was a Louis Pasteur in 1864 who made a full-proof version of Redi’s experiment. Eventually the hypothesis that living things came from other living things became so thoroughly studied that it became a theory, which is a very well supported hypothesis. This theory was called biogenesis and it is still believed in today.

Biology is the study of life. It is believed that all living things share characteristics. We are all made up of cells, which are clusters of living matter blocked from their surroundings by a barrier. Cells can reproduce, grow and respond to what is around them. Some organisms are unicellular or multicellular, and can contain trillions of cells. All organisms can reproduce, either through sexual reproduction, which varies traits, or asexual reproduction, which results in two identical copies. There are two types of asexual reproduction, one being a single celled organism dividing in half, and the other, where a portion of the organism splits off and forms a new organism. All organisms are based on a universal code, DNA. We all grow and develop. Living organisms constantly need energy and materials. The combination of chemical reactions where organisms break down materials is the metabolism. We can keep a stable internal environment through the process of homeostasis. All living organisms change over time, and if this change is over a very long period of time, and is on a group it is called evolving.

There are different levels of organization in life, molecules, then cells, to groups of cells, then the organism, then the population, which is a group of one type of organism, to a community, where populations live together, then an ecosystem, which involves a community and it’s non living surroundings. Finally, the largest level of biological study is the biosphere, which includes everything on earth.

By: Jenell Louissaint