What is Biology? Biology Cycles The Scientific Method

What is Biology? Biology – the study of life Organisms - a living thing; one of many different forms of life Biologist – a person who studies life Cycle – a course or series of events or operations that repeats

What are the cycles of biology?

What are the cycles in biology? Energy cycle Energy is the ability to do work. Energy can transform, or change form, into different types. Law of conservation of energy – energy cannot be created or destroyed Heat – a form of energy resulting from the motion of particles in matter.

Energy cycle All energy for Earth’s process comes from the Sun.

What are the cycles in biology? Growth cycle Reproduction – the process of making new life DNA – deoxyribonucleic acid; a chemical in an organisms that contains the instructions for life Cell – the basic unit of life Protein – a chemical used by cells to grow and work

Growth cycles. Cells create proteins, which then direct chemical process to occur.

What are the cycles in biology? Evolutionary cycles Evolution – the changes in a population over time Species – a group of organisms that can reproduce with each other Speciation – the process of making a new species Extinct – when no members of a species are alive Adaptation – an adjustment to environmental conditions

Evolutionary Cycles

What are the cycles in biology? Ecological cycle Ecology – the study of interactions among living things and the nonliving things in their environment Ecologist – a person who studies ecology Ecosystem – all of the living things found in any particular area Stimulus – anything to which an organisms reacts

Ecological Cycle

The Scientific Method

A series of steps used to test possible answers to scientific questions. Specimen – a sample; an individual item or part considered typical of a group or whole

The Scientific Method Observation Scientists gather information about the world around them. They use their senses to gather information. They develop questions based on their observations

The Scientific Method Question When scientists see something they don’t understand, they develop questions and try to find the answers.

The Scientific Method Hypothesis Hypothesis – an educated guess or a prediction that can be tested Hypotheses do not have be proved correct!

The Scientific Method Experiment Experiment is the procedure used to test whether a hypothesis is correct. Control group – control has no variable, or factor, changed Experimental group – variable; the one factor to be tested Data – information collected from an experiment

The Scientific Method Analysis Analysis – making sense of the results of an experiment Scientists compare the results to the hypothesis and explain what the data means

The Scientific Method Communication After scientists have completed their analysis, they discuss the results The hypothesis does not have to be correct. The experiment is repeated, whether the results confirm or deny the hypothesis

Theory Theory – a well tested explanation that makes sense of a great variety of scientific observations Theories have been tested several times and the results are consistent Theories can be proven false! –In the Middle Ages, people believed the Sun revolved around the Earth.

Hypothesis vs. Theory Hypothesis have been tested few times Results are not always consistent Used to explain human opinions Theories have been tested many times Results are consistent Used to explain natural events

Statistical Variability The variation in data that occurs during many experiments –Example: At home, you weigh 120 lbs, but at the doctors office you weigh 124 lbs. Some variation is avoidable, some unavoidable Variation can be minimized by using controlled experiments –Control: the part of the experiment that doesn’t change

Experimental Error All experiments have some amount of error Avoid error by keeping equipment clean, using equipment properly, using and measuring chemicals properly, etc. Unavoidable experimental error occurs because of factors not in your control

Experimental Errors Avoidable (human) –Dry beakers well –Wipe of dust on balances –Line up metersticks –Don’t use broken instruments (that you know of) Unavoidable (machine) –Worn out parts –Material you receive is tainted or not pure –Parts not working correctly