HonorHonors s

BiologBiologyy

Ch. 1Ch. 1

The Study The Study of Lifeof 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 factorb)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

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

Paramecium and Didinium

Leaf tissueLeaf tissue

B. Organization

O

H H

CH2OH

SubatomicElectronElectronNeutronNeutronProtonProton

NitrogenNitrogenCarbonCarbonHydrogenHydrogen OxygenOxygen

DNADNAGlucoseGlucoseWaterWater

NucleusNucleusChloroplastChloroplastMitochondrionMitochondrion

Nerve CellNerve Cell

Atomic

Molecular

Organelle

Cellular

B. Organization

TissueNervous TissueNervous Tissue

BrainBrain

NervousNervousSystemSystem

PronghornPronghornAntelopeAntelope

Organ

Organ System

Organism

B. Organization

PopulationHerd of PronghornsHerd of Pronghorns

HawkHawk

WaterWater

Earth’sEarth’ssurfacesurface

Community

Ecosystem

Biosphere

PronghornsPronghorns

HawkHawk GrassGrassPronghornsPronghorns

SnakeSnakeBushesBushes SoilSoilAirAir

SnakeSnake

C. Growth and development 1. Growth:

- increase in size or number of cells

Click on picture

Sea Urchin Early

Embryonic Developme

nt

Sea Urchin Early

Embryonic Developme

nt

C. Growth and development 1. Growth:

- increase in size or number of cells

Roundworm

Embryonic Developme

nt

Roundworm

Embryonic Developme

nt

Click on picture

C. Growth and development 2. Development:

- increase in complexity

Monarch Butterfly

Development

Monarch Butterfly

Development

Egg Hatching

C. Growth and development 2. Development:

- increase in complexity

Monarch Butterfly

Development

Monarch Butterfly

Development

Larva Eating

C. Growth and development 2. Development:

- increase in complexity

Monarch Butterfly

Development

Monarch Butterfly

Development

Chrysalis Pupating

C. Growth and development 2. Development:

- increase in complexity

Monarch Butterfly

Development

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 fission Human egg and sperm

Click on picture

D. Reproduction

- asexual vs. sexual

parents:

offspring:

1 2

genetically identical

genetically unique

D. Reproduction

- asexual vs. sexual

parents:

offspring:

1 2

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.E. Responds to stimuliResponds to stimuli

E.E. Responds to stimuliResponds 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 food2. heterotrophs:

- get food from other organisms

Praying Mantis eating a Grasshopper

F. Requires energy

Praying mantis eating a snake.

G.G. Maintains homeostasisMaintains homeostasis - the stable

internal environment necessary for life

H.H. Adaptations evolve over Adaptations evolve over timetime

TheTheEndEnd