Text 1.2. What Do Biologists Do?

■ Essential targets: By the end of this text you should be able to:

● describe what biologists do;

●define the different levels of biological organization;

● list the main elements of a scientific method.

Pre-reading

■ Working in pairs, discuss these questions with your partner. Then scan the text to find the answers and compare them with your discussion.

1. What do biologists study?

2. What careers in biology can you think of?

3. What areas of biology do you consider as the most important for human society nowadays? Give your reasons.

4. Could you name the key elements of biological investigations?

■ Read the given texts and make your essential assignments:

Part A. The levels of biological organization:

Biologists study every aspect of life at every level of its organization, from the atoms that make up biological molecules to the ecosystems that form the biosphere.

Here are the levels of biological organization from atoms, the smallest components of living things, to the biosphere, the entire living planet:

▪ Biosphere

▪ Ecosystem

▪ Population

▪ Individual

▪ Organ system: digestive system

▪ Organ: stomach

▪ Tissue: smooth muscle

▪ Cell: smooth muscle cell

▪ Organelle: Mitochondrion

▪ Macromolecules: proteins

▪ Chemical building blocks or monomers: amino acid

▪ Atoms: carbon

Part B.Aspects of biology:

Modern biology is an enormous subject that has many branches. Specialists in some branches include:

● molecular biologists and biochemists who work at the chemical level, with the aim of revealing how DNA, proteins, and other molecules are involved in biological processes;

● geneticists who study genes and their involvement in inheritance and development;

● cell biologists who study individual cells or groups of cells, often by culturing them outside organisms; thee investigate how cells interact with each other and their environment;

● physiologists who find out how organ systems work in a healthy body;

● pathologists who study diseased and dysfunctional organs;

● ecologists who study interactions between organisms and their environment. Some focus their attention on whole organisms; others study populations, individuals of the same species living together at one location.

There are also biologists who specialize in particular groups of organisms; for example, bacteriologists study bacteria, botanists study plants, and zoologists study animals.

Biologists are employed in many fields including conservation and wildlife management, industry, health care, horticulture, agriculture, zoos, museums, information science, and marine and freshwater biology. In addition, many biologists are employed as teachers, lecturers, or research workers.

Part C.A letter to students who study biology:

Dear Students,

I am writing this letter to welcome all of you who are about to begin your first year course in Biology here at the university. You might think it is a little early for me to ask you to think about what you will do when you leave here in three years` time. However, our science, like any other, has so many different areas it is impossible to study them all. The first thing you will have to think about is specializing. This letter is to offer you some suggestions to think about for your future.

As you know, there are four main areas of biology that we shall concentrate on in the coming years. Biology can be divided into zoology, the study of animal life, and botany, the study of plant life. We shall also study molecular biology, the study of how the building blocks of living things, the cells, work. Another topic of interest is genetics, how biological information is passed on from one generation to the next: that is, inheritance. You should specialize, but you will also need to know about all of these four areas of study. Plants and animals do not live separately from each other; all living things are made up of cells and one of things genetics tells us is how plants and animals adapt to the conditions around them.

So what about after the course is over and you have graduated in Biology? Can you have a career in biology? For those who choose to specialize in genetics or molecular biology there are important career opportunities in medicine. At the present time, there is a great deal of research going on in gene therapy where biologists are working with doctors and chemists to find new ways of treating diseases. Other biologists are looking at ways of changing the genetic composition of the plants we grow for food; of making them more able to fight diseases and at the same time produce more food.

We are experiencing a period of climatic change too, and this is having an effect on the way animals and plants live. The science of ecology is becoming more and more important; biologists who specialize in zoology are working in many parts of the world. Some are working to protect species like the tiger, which are seriously threatened by climate change. Others are investigating wildlife from the smallest insects to the largest mammals, trying to understand how they all live together. Botanists are looking at the effect new types of food crops have on the environment and how changes in that area can affect our general health. There is even a new area of biology called astrobiology, which is looking at the possibilities of life on other planets – but perhaps that is something for the more distant future.

Whatever you specialize in, as long as there is life on this (or any other) planet, there is work for a biologist.

Good luck and enjoy your studies!

Jean Shearer

Professor of Biology.

Part D.The scientific method:

The definition of biology states that it is a `scientific study`. This distinguishes biology from other ways of studying life. However, there is no single rigid scientific method that biologists use: there are numerous ways of studying life scientifically. Nevertheless, biological investigations usually include one or more of the following key elements:

- observing: making observations and taking measurements

- questioning: asking questions about observations and posing a problem

- hypothesizing: formulating a hypothesis, a statement that explains a problem and can be tested

- predicting: stating what would happen if the hypothesis were true

- testing: testing the hypothesis, usually by carrying out a controlled experiment aimed at producing data that will either support or contradict the hypothesis

- interpreting: interpreting the test results objectively and drawing conclusions that accept, modify, or reject the hypothesis.

A biologist may start an investigation by making observations or by using observations described by other biologists. Such observations may be obtained directly by the senses, such as listening to a bird song, or indirectly through instruments such as recording the song on a computer system. On the other hand, an investigation may start simply by a biologist having an idea that something happens in a particular way, and then the idea will be tested by making observations or carrying out experiments to see if it is valid. A hypothesis is suggested and then tested in all investigations. One essential aspect of a scientific experiment is that it can be repeated by other scientists working independently.

A typical hypothesis makes a clear link between an independent or manipulated variable and a dependent variable. Variables are conditions or factors (such as light, temperature, or time) that can vary or may be varied. In an experiment, the independent or manipulated variable is the one that is systematically changed; the dependent variable is the effect or outcome that is measured. For example, when investigating the activity of an enzyme at different temperatures, temperature is the independent variable that is manipulated by the scientist; rate of reaction is the dependent variable that is measured at each temperature. Other variables called controlled variables are kept constant or controlled at set levels.

At the end of an experiment, the results must be interpreted as objectively as possible. Sometimes they are so clear that it is obvious whether they support or contradict the hypothesis. Often, however, results are variable and need statistical analysis before conclusions can be made. The conclusions may lead to the hypothesis being accepted, modified, or rejected. Even if results support hypothesis, it is accepted only tentatively because it can never be proved completely. However, it only needs a single contrary observation to refute a hypothesis (prove it wrong or incomplete). A hypothesis is therefore only the best available explanation at any time. This makes biology a highly dynamic subject and not merely a collection of facts.

A typical sequence of events in a scientific investigation:

▪ Observations

▪ Questions

▪ Hypothesis (accept, modify, reject)

▪ Predictions

▪ Experiments

▪ Test experiments

▪ Control experiments

▪ Results

▪ Interpretation

▪ Conclusion (accept, modify, reject)

■ Glossary of essential terms for you to know

■ Your Essential Assignments

I. Quick check

1 What is the difference between a physiologist and a pathologist?

2 Which is the highest level of biological organization on Earth?

3 In an experiment in which the rate of photosynthesis of a plant is measured at different light intensities, which is the independent (manipulated) variable and which is the dependent variable?

4 How can biologists help animals in the wild?

5 What is astrobiology?

II. Find synonyms among the pool of words:

III. Fill in the missing words:

IV. Use monolingual English dictionary and write down what could the words given below mean:

inheritance, interpretation, species, hypothesis, to refute.

V. Match the words with their definitions:

VI. Find English equivalents to the following word combinations from the text:

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