Chapter 1 The science of Life 1.1 The World of biology 1.2 Themes in biology 1.3 Study of Biology 1.4 Tools and Techniques

Section 1 – The world of biology Goals Relate the relevance of biology to our daily life. Describe the importance of biology in society. List and explain the characteristics that living things share. Summarize the levels of organization animals exhibit. Compare and contrast homeostasis and metabolism as well as growth, development and reproduction

Prefix comes before root word, suffix comes after, Greek or Latin based. - Prehistoric - Pre (before) Historic (written or recorded history) Atypical Epiglottis Microorganism Suffix - Biology - Bio (life) Logy (study of) Zoology Ecology Histology

Biology and Society Ethics and morals determine what the public will allow science to research. - not always the same Safety is always on the minds of scientists. - outbreaks, pollution and test subjects Knowledge of science is important for government policy . - pollution levels and funding We can use biology to: Cure diseases and treat cancer, preserve environment, save species, improve food supply...

Characteristics of Living Organisms 1. Organized and Made of Cell(s) - unicellular or multicellular Atom – Molecule – Organelle – CELL – Tissue – Organ – System – Organism 2. Response to Stimuli - chemical or physical - smell or touch 3. Homeostasis - maintaining stable internal conditions despite changing external factors - shivering when cold to maintain body temp or drinking more water when it’s hot outside.

4. Metabolism - sum total of all chemical reactions in the body - photosynthesis and cellular respiration 5. Growth and Development - growth occurs by cells grown AND adding more cells through cell division - development occurs as cells specialize and organisms mature 6. Reproduction - needed for species survival and not that of the individual - asexual (prokaryotes like bacteria) or sexual (eukaryotes like bunny rabbits) 7. Change over time - heritable short term adaptations or long term species evolution

Section 2 – Themes of Biology Life is very diverse consisting of single cell bacteria up to whales and nake mole rats! Life is unified due to its common ancestry and shared genetic code. - we share genes with plants, flies and mushrooms - all cells have organelle that perform the same function Three Domains of Life Bacteria – Archaea – Eukarya Six Kingdoms of Life Bacteria – Archaea – Animalia – Plantae – Fungi – Protista All living things share resources and energy with other living organisms

Section 3 – Study of Biology Evolution is how scientists attempt to explain the diversity and unity of life. - unity because all living things have a common ancestor - diversity because of how different locations on Earth have different conditions. Evolution occurs through the process of natural selection - "survival of the fittest" - results in adaptations that improve survivability and reproductive success Section 3 – Study of Biology All parts of this section are significant. Spend a lot of time studying this section. This process is the same for chemistry, physics or any other science.

Scientific Method: An “orgnaized approach” that doesn’t always follow an exact pattern. based on the idea events have a natural cause also based on the idea that the laws of nature work the same everywhere Observe with your sense or a tool to aid the senses. Formulate a question. Hypothesize a possible answer based on reason. Predict what will happen when the hypothesis is tested. Experiment in a controlled way to test predictions. Analyze and interpret date, make graphs and perform statistics. Communicate your findings so others may benefit. Sometimes science is observational or “descriptional” research. It doesn’t answer how or why, but what happens. Control group is the benchmark, the experimental group is tested. Independent variable is the one changed. Depended variable responds to the change in independent variable.

Section 4 – Tools and Techniques We use the metric system in science – base 10 or powers of 10 “Slide the decimal” Seven fundamental base units can be combined into many derived units. second, meter, kilogram volume, density Let’s do these together, BE SURE TO TAKE NOTES! WILL BE ON TEST! 1,300m  km 400cm  m 350mm  cm 25dam  cm Technology is the use of knowledge to solve problems, tools are one result. Microscopes are either light based or electron based. (More notes for lab later) - light microscopes can be compound or stereoscope - electron microscopes can be scanning or transmission

Light Microscope Uses light like our own eyes. Glass lenses bend light to magnify an image. Used on small to very small objects, but has limits. Compound Microscope uses multiple lenses and give a “bottom up” view. Dissection scopes give a “top down” view.

Electron Microscope Uses a beam of charged particles (electrons) to view extremely small objects. Transmission (TEM) passes a beam through a very thin sample. Scanning (SEM) bounces a beam off a sample.

SEM

TEM

Pros & Cons Light microscopes can show living things in action but have limits to how much they can magnify. Electron microscopes can show processes or living things. Samples must be dead. Light microscopes are portable and cheap!