Science is an organized way of understanding the world. It is a process that only relates to the natural world and shows patterns and connections. Explanations based on evidence provide insight into understanding patterns in nature and making helpful predictions.
Scientific Method
The scientific method involves several steps:
- Observing and asking questions
- Observation involves noticing and describing in an orderly way, using the five senses.
- Inferring and forming a hypothesis
- Inference is a logical interpretation based on observations, while a hypothesis is a scientific explanation that can be tested and supported or rejected.
- Controlled Experiment
- This involves changing only 1 variable at a time, with the independent variable being changed by the scientist (cause), the dependent variable responding to the IV (effect), the experimental group being exposed to the IV, the control group being exposed to all the same conditions as the experimental group except the IV, and the controlled variables remaining the same for all groups.
- Collecting and Analyzing Data
- This includes quantitative data (quantity, numbers) and qualitative data (quality, descriptions).
- Drawing Conclusions
- The evidence supports or refutes hypotheses.
Science in Context
Bias is a personal preference that is not scientific and prevents science from being objective. It can be stopped by collaboration or peer review. A scientific theory is a well-tested explanation that unifies a broad range of observations and hypotheses, enabling scientists to make accurate predictions about new situations.
Studying Life
Biology is the study of life, including various organisms such as bacteria, protists, fungi, plants, and animals. The properties of life include a universal genetic code (DNA/RNA), growth and development, response to the environment, cells, evolution as a group, obtaining and using material and energy, maintaining a stable internal environment (homeostasis), and reproduction.
The Nature of Matter
Matter is defined as anything that occupies space and has mass. Elements are substances that cannot be broken down into simpler substances, while compounds consist of two or more different elements in a fixed ratio. Essential elements such as carbon, oxygen, hydrogen, and nitrogen make up a significant portion of the weight of organisms.
Atom is the smallest unit of matter that retains the properties of matter and has subatomic particles such as protons, neutrons, and electrons. Isotopes are atoms of an element with the same number of protons but different numbers of neutrons and atomic mass. Chemical bonds include covalent bonds, non-polar covalent bonds, polar covalent bonds, ionic bonds, hydrogen bonds, and van der Waals forces.
Properties of Water
Water is formed via a polar covalent bond and is polar, with oxygen having a slightly negative charge and hydrogen having a slightly positive charge. Hydrogen bonds form between the hydrogen of one water molecule and the oxygen of another, resulting in cohesion, adhesion, surface tension, and high heat capacity. These properties of water make it essential for various biological processes.
