Honors Biology Ch. 1 The Study of Life

I. Science -an ongoing, inquiry-based process to understand the world around us -relies on evidence -challenges accepted theories -undergoes peer review

II.Scientific Method -a logical series of problem solving procedures A.Ask an Experimental Question B.Form a Hypothesis - a testable explanation

C.Collect Data 1.Controlled Experiment a)Experimental Group: -the part of an experiment exposed to the experimental factor b)Control Group: -the part of the experiment that does not receive the experimental factor -used for comparison

2.Experimental Design a)Manipulated (independent) Variable - the one variable being tested (experimental factor) b)Responding (dependent) Variable - a variable that is measured in a controlled experiment - changes in the responding variable result from changes in the manipulated variable c)Constants (Controlled Variables) - factors that remain fixed during an experiment

3.Data -information gained from observations -Quantitative: numerical (metric system used) -Qualitative: descriptive Jane Goodall collecting qualitative data on chimpanzee behavior

D.Analyze the Data -look for patterns to explain the data -graphs, tables, and statistical analysis used

E.Report Conclusions - Is the hypothesis supported or rejected by the data? - Experimental findings are subjected to peer review. - If the experiment has merit, it may be published.

F.What is a Theory? - explanation that is continually supported by evidence - help us understand the world - used to make predictions

III.Biology -the science of life -8 Characteristics of Life distinguish living organisms from nonliving

A.Cellular Structure Paramecium and Didinium Leaf tissue

B.Organization O H H CH 2 OH Subatomic ElectronNeutronProton NitrogenCarbonHydrogenOxygen DNAGlucoseWater NucleusChloroplastMitochondrion Nerve Cell Atomic Molecular Organelle Cellular

B.Organization Tissue Nervous Tissue Brain Nervous System Pronghorn Antelope Organ Organ System Organism

B.Organization Population Herd of Pronghorns Hawk Water Earth’s surface Community Ecosystem Biosphere Pronghorns Hawk Grass Pronghorns Snake Bushes Soil Air Snake

C.Growth and development 1.Growth: -increase in size or number of cells Click on picture Sea Urchin Early Embryonic Development

C.Growth and development 1.Growth: -increase in size or number of cells Roundworm Embryonic Development Click on picture

C.Growth and development 2. Development: - increase in complexity Monarch Butterfly Development Egg Hatching

C.Growth and development 2. Development: - increase in complexity Monarch Butterfly Development Larva Eating

C.Growth and development 2. Development: - increase in complexity Monarch Butterfly Development Chrysalis Pupating

C.Growth and development 2. Development: - increase in complexity Monarch Butterfly Development Adults Emerging

C.Growth and development 2. Development: - increase in complexity Common Whelk

D.Reproduction - asexual vs. sexual E. coli showing binary fissionHuman egg and sperm Click on picture

D.Reproduction - asexual vs. sexual parents: offspring: 12 genetically identical genetically unique

D.Reproduction - asexual vs. sexual parents: offspring: 12 genetically identical genetically unique

1 cell splitting into 2 cells Asexual or sexual? D.Reproduction

Asexual or sexual? Beetle pollinating a flower D.Reproduction

Asexual or sexual? D.Reproduction

Asexual or sexual? Hydra budding D.Reproduction

Asexual or sexual? Earthworms Mating D.Reproduction

Asexual or sexual? Sheep clones D.Reproduction

E.Responds to stimuli

F.Requires energy 1. autotrophs: - make their own food - get food from other organisms Cycad photosynthesizing

F.Requires energy 1. autotrophs: - make their own food 2. heterotrophs: - get food from other organisms Praying Mantis eating a Grasshopper

F.Requires energy Praying mantis eating a snake. Praying mantis eating a snake.

G.Maintains homeostasis -the stable internal environment necessary for life

H.Adaptations evolve over time

The End