Chapter 1The Science of Biology

Embryology: the study of the prenatal development of an organism from the fertilized egg. Embryologists study tissue and organ formation and identify birth defects.

In Computational Biology, scientists use mathematical models, algorithms and computer simulations to understand biological systems and relationships. It involves analysing biological data, such as the sequence of amino acids in a protein.

Observation gathers information about the problem, using the five senses and earlier research; on the basis of observations, a hypothesis is formed.

Experimentation is the most basic step: experiments test all hypotheses; the incorrect ones are rejected and the proved one is accepted. Without experiments a hypothesis cannot become a theory.

Fossils are the remains of plants and animals that were preserved in rocks and other geological formations. The oldest fossil is of a cyanobacterium, about 3.5 billion years old.

The book: the human body contains trillions of cells; various cells possess unique structures.

When scientists do experiments, they arrange two settings: the experimental group and the control group. In the CO₂ experiment, the plant without CO₂ is the experimental group and the plant given CO₂ is the control group.

Quinine was the only remedy for malaria from the 17th to the 20th century.

The Aedes mosquito transmits dengue fever.

Biology is the science of life. It comes from the Greek words "bios" (life) and "logos" (study), and explores the structures, functions and interactions of living organisms.

Zoology (animals), Botany (plants) and Microbiology (microorganisms).

The study of microorganisms, such as bacteria and microscopic fungi: their structures, functions, habitats, reproduction and impacts on health and environment.

Histology is the microscopic study of tissues. Cytology is the study of cells, the building blocks of life.

It deals with the study of biological molecules like carbohydrates, proteins, lipids and nucleic acids. Molecular biologists also create genetically modified organisms.

Taxonomy deals with the classification of organisms into groups on the basis of similarities and differences. It helps to organize the diversity of life, identify new species and study evolutionary relationships.

Ecology deals with the relationships between organisms and their environment. The food chain shows how organisms are connected for energy and nutrients.

The branch in which we study the components of the immune system and their role against diseases. Immunologists develop vaccines.

Anatomy studies the internal physical structure of organisms (organs); Histology is the microscopic study of tissues.

The study of the structure and reactions of chemical substances present in living systems, e.g. reactions of photosynthesis and respiration.

The study of the principles of Physics which apply to biological processes, e.g. the rules of lever and motion for muscles, bones and joints.

The use of the principles of statistics to analyse and interpret data related to living organisms.

The use of living organisms or their components to develop beneficial products or processes, e.g. bacteria used to produce insulin for diabetic patients.

The study of organisms from an economical point of view: the cost and profit of biological projects, e.g. producing a new crop variety.

The study of the distribution of living organisms in different geographical regions of the world.

Medicine and surgery, dentistry, pharmacology, physiotherapy, agriculture, horticulture, forestry, animal husbandry, biotechnology, forensics.

The therapy used to restore movement and physical function of the body that has been impaired by disease or injury, by exercise and modalities such as massage. It needs a 4-year BS degree.

Horticulturists cultivate fruits, vegetables, flowers and ornamental plants. Foresters manage and conserve forests and wildlife.

They analyse physical evidence from crime scenes in criminal investigations.

Because researchers from various disciplines work together to solve complex problems; interdisciplinary teams use the strengths of each discipline and reach quicker, sustainable solutions.

A project to sequence and map the human genome, completed in 2003, involving molecular biology, genetics, informatics and computer science.

"We made every living thing from water." (Al-Anbiya, Verse 30). It hints at the common origin of all living things in water.

Al-Mominoon, Verse 14: "Then fashioned We the drop a clot, then fashioned We the clot a little lump, then fashioned We the little lump bones, then clothed the bones with flesh."

Specific steps used by scientists to solve scientific problems (called biological method in Biology): recognition of the problem, observations, hypothesis, deduction, experiments, results.

Qualitative observations cannot be measured with numbers (colour of a flower); quantitative observations are measurements expressed in numbers (number of birds). Quantitative ones are more accurate.

A tentative answer to a scientific problem. It is a proposed statement, matches the available observations, can be tested by experiments, and can always be disproved.

The logical result of a hypothesis, usually an "if–then" statement. "If iron deficiency causes the symptoms, then adding iron to the soil will improve the leaf colour."

Because they are invariable, measurable and recorded in numbers; different people get the same value.

They summarise them with statistics and graphs, list references, publish in journals and books, and present them in national and international meetings and seminars.

A hypothesis repeatedly proved by experiments becomes a theory; it is supported by extensive evidence. Example: the theory of evolution.

A scientific law is a uniform or constant fact of nature, reached when a theory is proved again and again: Hardy–Weinberg law, Mendel's laws of inheritance.

A hypothesis is a tentative answer not yet tested; a theory is a hypothesis proved by experiments and supported by extensive evidence.

Laveran, a French army physician, who saw microorganisms in a patient's blood (book: 1878) and named them Plasmodium.

Hypothesis: Plasmodium is the cause of malaria. Deduction: if Plasmodium is the cause, then all malarial patients should have Plasmodium in their blood.

"Mosquitoes transmit Plasmodium and so are involved in the spread of malaria." (A. F. A. King, 1883)

The experiment was risky: if the hypothesis was true, the healthy person would get malaria. So he used sparrows and Culex mosquitoes.

It multiplies in the walls of the mosquito's stomach and then moves into its salivary glands, from where it enters the next host when the mosquito bites.

Why divide Biology

Biology is a vast field that explores the incredible diversity of life on Earth. To better understand this complexity, scientists have divided Biology into fields and branches. No one person can master all of it.

Benefits of specialization

1. Problem

"Why does this plant grow faster in shade than in direct sunlight?"

2. Observations

Measure the height of plants in shade and in sun over some weeks (quantitative); read earlier research on light and growth.

3. Hypothesis

"Direct sunlight (strong light and heat) slows the growth of this plant species; it grows best in partial shade."

4. Deduction

"If shade promotes growth, then identical plants kept in shade will grow taller than those kept in direct sunlight, other conditions being the same."

5. Experiment

Take, say, 20 similar seedlings in the same soil and pots; give the same water. Keep 10 in direct sunlight (control group, normal condition) and 10 under a shade net (experimental group). Measure height every week for 6 weeks.

6. Results

Calculate the average height of each group and draw a graph. If the shaded plants are clearly taller, the hypothesis is supported; repeat the experiment to confirm, then publish the result.

Biology is closely linked with other natural sciences. These connections help us understand life processes, environmental interactions and the complexities of living organisms.

Biophysics (Physics)

The study of the principles of Physics which apply to biological processes, e.g. the rules of lever and motion to understand muscles, bones and joints.

Biochemistry (Chemistry)

The study of the structure and reactions of chemical substances in living systems, e.g. the reactions of photosynthesis and respiration.

Biostatistics (Statistics)

The principles of statistics used to analyse and interpret data related to living organisms; crucial in research, healthcare and public health.

Biogeography (Geography)

The study of the distribution of living organisms in different geographical regions, and the influence of climate change on it.

Bio-economics (Economics)

The study of organisms from an economical point of view; the cost and profit of biological projects, e.g. new crop varieties.

Computational Biology (Computer Science)

Mathematical models, algorithms and computer simulations to understand biological systems, e.g. analysing the sequence of amino acids in a protein.

After FSc with Biology, students can select further studies for diverse careers:

Health professions

Agriculture and animals

Science and technology

Science is a collaborative field in which researchers from various disciplines work together to solve complex problems. Interdisciplinary teams tackle problems more efficiently by leveraging the strengths of each discipline, often leading to quicker and sustainable solutions.

Human Genome Project

Aimed to sequence and map the human genome; completed in 2003; involved molecular biology, genetics, informatics and computer science.

Climate change research

Needs atmospheric science, ecology, economics and sociology together.

Medical research

Cancer research involves oncologists, biologists, biochemists, geneticists, pharmacologists and statisticians.

Robotics and Artificial Intelligence

Combines computer science, engineering, mathematics, neuroscience and psychology; gave robotic systems, autonomous vehicles, machine learning and natural language processing.

Space exploration

NASA and the International Space Station join astrophysics, planetary science, engineering, Biology and medicine to investigate the cosmos.

Hypothesis

A tentative answer to a scientific problem, based on observations. Experiments test it; the incorrect hypotheses are rejected and the proved one is accepted.

Theory

When experiments prove a hypothesis correct, scientists use it for making further hypotheses. When new hypotheses are again proved by experiments, the original hypothesis becomes a theory. A theory is supported by extensive evidence and repeatedly validated by many researchers, e.g. the theory of evolution.

Law or principle

Scientists keep on testing the theory and try their best to disprove it. If a theory is proved again and again by experiments, it becomes a law or principle. A scientific law is a uniform or constant fact of nature, e.g. Hardy–Weinberg law, Mendel's laws of inheritance.

1. Recognition of a problem

Identifying and defining the scientific problem to investigate, e.g. "What factors make these plants grow taller?"

2. Observations

Using the five senses and earlier research; observations are qualitative (colour) or quantitative (number), the latter more accurate.

3. Hypothesis

A tentative answer that matches the observations, can be tested and can be disproved.

4. Deduction

Logical "if–then" results of the hypothesis.

5. Experiments

The most basic step: experimental and control groups test the deductions; wrong hypotheses are rejected.

6. Results

Data are analysed with statistics and graphs, published in journals and presented at seminars.

Laveran: the cause

In 1878 (book), the French army physician Laveran examined the blood of a malarial patient under a microscope and noticed microorganisms, named Plasmodium. Scientists then hypothesised "Plasmodium is the cause of malaria"; examining 100 patients and 100 healthy persons showed most patients had Plasmodium.

A. F. A. King: the carrier

In 1883 King listed 20 observations (people outdoors got more malaria; nets and smoky fires protected) and suggested the hypothesis: "Mosquitoes transmit Plasmodium and so are involved in the spread of malaria."

Ronald Ross: the proof in birds

The British army physician Ross, in India, found Plasmodium multiplying in the stomach of an Anopheles mosquito that had bitten a patient. Using sparrows and Culex mosquitoes, he showed Plasmodium moves to the mosquito's salivary glands and infects healthy sparrows.

Italian biologists: the proof in man

In 1898, Italian biologists let an Anopheles mosquito bite a malarial patient and then a healthy man, who became ill with malaria. It was confirmed that mosquitoes transmit Plasmodium.

Background

King's deduction: "If mosquitoes are involved in the spread of malaria, then Plasmodium should be present in mosquitoes." Ronald Ross, a British army physician working in India, tested it.

Experiment 1: mosquito and patient

He allowed a female Anopheles mosquito to bite a malarial patient. He killed this mosquito and found Plasmodium multiplying in its stomach.

Experiment 2: sparrows and Culex

Using humans would be risky, so he allowed female Culex mosquitoes to bite a sparrow suffering from malaria. He studied the mosquitoes at different times: Plasmodium multiplied in the walls of the stomach and then moved into the salivary glands. He allowed infected mosquitoes to bite healthy sparrows; these sparrows got malaria, and their blood had many Plasmodia.

Conclusion

It proved the hypothesis: mosquitoes transmit Plasmodium, so mosquitoes are involved in the spread of malaria.

Biology

Biology is the science of life; "bios" = life, "logos" = study.

Major fields

Zoology (animals), Botany (plants), Microbiology (microorganisms such as bacteria and microscopic fungi).

Branches

Hypothesis

A tentative answer of a scientific problem, which matches the observations, can be tested and can be disproved.

Deduction

The logical result of a hypothesis in "if–then" form, which can be tested.

Experiments

In a successful experiment one hypothesis is proved correct and the alternate hypotheses are proved incorrect. Two settings are arranged:

If photosynthesis stops only in the experimental group, the need of CO₂ is proved. The control group shows that any change is due to the tested factor alone.

In the Holy Quran there are several verses that highlight concepts of Biology and encourage exploring and reflecting on the study of life.

Origin of life in water

"We made every living thing from water." (Al-Anbiya, 30) All organisms contain 60%–90% water, hinting at a common origin in water.

Creation of man

"He created man from clay like the potter." (Al-Rehman, 14) and "Then fashioned We the drop a clot, … then clothed the bones with flesh." (Al-Mominoon, 14) describe the stages of human development.

Variety of animals

"Allah hath created every animal from water. Then some of them creep upon their bellies, others walk on two legs, and others on four." (Al-Noor, 45) Early life arose in water (fishes), then animals with limbs appeared.

Problem 1: cause of malaria

Observations: marshes, quinine, marsh water harmless, Plasmodium in patients' blood (Laveran). Hypothesis: Plasmodium causes malaria. Deduction: all patients should have Plasmodium. Experiment: blood of 100 patients (experimental) and 100 healthy (control) examined. Result: most patients had Plasmodium; hypothesis true.

Problem 2: entry of Plasmodium into man

Observations (King 1883): outdoors, nets, smoky fires. Hypothesis: mosquitoes transmit Plasmodium. Deduction: Plasmodium should be present in mosquitoes. Experiments: Ross (sparrows, Culex); Italian biologists 1898 (man, Anopheles). Result: mosquitoes spread malaria.