The Science of Biology

1
The Science of Biology

• Modern Biology Chapter 1,
• Section 4.3, Section 14.1
• Biology Exploring Life Chapter 1 Sections
  2.1-2.2

2
Scientific Methods

• Observation
• Purpose problem/question
• Hypothesis
• Experiment
• Data collection
• Conclusion

3
Hypotheses

• Testable explanations for observations
• Research hypothesis
• Prediction
• If then
• Null hypothesis
• No significant effect of experimental treatment
• Accepted or rejected based on statistics

4
Experiments

• Control and experimental groups
• Variables
• Research variables
• Independent variable
• Dependent variable
• Control variables (constants)

5
Scientific Writing Lab Reports

• Title
• Introduction
• Materials and Methods
• Results
• Discussion

6
Title

• Independent variable
• Dependent variable
• Scientific name of experimental organism

7
Introduction

• Purpose
• Background information
• Hypothesis
• Brief summary of experiment

8
Materials and Methods

• Materials
• Variables and controls
• Procedure
• Data collection

9
Results and Discussion

• Results
• Data presentation (figures, graphs, tables, etc.)
• Written descriptions (captions, paragraphs, etc.)
• Discussion
• Data analysis and interpretation
• Evaluation of hypotheses
• Experimental error
• Significance

10
Microscopy

• Magnification v. resolution
• Microscopes
• Compound light microscope (LM)
• Electron microscopes (EM)
• Transmission electron microscope (TEM)
• Scanning electron microscope (SEM)
• Scanning tunneling electron microscope (STM)

11
Characteristics of Living Things

• Homeostasis
• Metabolism
• Cells
• Growth and Development
• Reproduction and Heredity
• Organization

12
Homeostasis

• Stability
• Maintaining a constant internal environment
  within a changing external environment
• Responses to various stimuli
• Checks and balances
• Feedback mechanisms

13
Examples of Homeostasis

• Organ systems
• Cardiovascular
• Endocrine
• Excretory
• Respiratory
• Body temperature
• Endothermic or ectothermic
• Homeothermic or poikilothermic

14
Metabolism

• Energy
• Biochemical reactions in an organism in which
  energy is released or used
• Catabolism and anabolism

15
Examples of Metabolism

• Nutrition
• Autotrophic or heterotrophic
• Gas exchange
• Photosynthesis and cellular respiration
• Aerobic or anaerobic
• Digestion
• Growth, development, and repair

16
Cellular Organization

• Cells the fundamental unit of lifethe smallest
  entity that has all the properties of life
• Most basic level of all life processes
• Unicellular or multicellular
• Prokaryotic or eukaryotic

17
Growth and Development

• Cell enlargement
• Cell division
• Cell differentiation

18
Reproduction

• Generation of offspring
• Propagation (continuation) of species
• Asexual or sexual

19
Heredity

• DNA the genetic material
• Inheritance transfer of genetic information from
  one generation to the next
• Evolution hereditary changes over time in a
  population of organisms

20
Levels of Organization

• Subatomic particles
• Atoms/elements
• Compounds/molecules
• Organelles
• Cells
• Tissues
• Organs

• Organ systems
• Organisms/species
• Populations
• Communities
• Ecosystems
• Biomes
• Biosphere

21
Atoms Molecules

• Chlorophyll molecule

22
Organelles

• Little cell parts with certain jobs
• chloroplast

23
Cells

• Unit of structure and function

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Tissues

• Group of cells with the same structure and job
• muscle tissue

25
Organ

• Group of tissues with the same structure and job

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Organ System

• Several organs
• with the same
• job

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Organism

• Complete and entire living thing

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Population

• A group of the same kind of organism found in a
  certain area

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Community

• All the organisms in an area living and
  interacting with each other

30
Ecosystem

• A community and
• its environment

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Biome

• A large area
• with similar
• ecosystems
• coral reef

32
Biosphere

• All the organisms and environments on earth

33
Scientific MethodsExample

• A student wants to find out if fertilizer will
  make her beans grow better. She plants six rows
  of bean plants in her garden. Each row contains
  the same number of plants. Three rows of plants
  get fertilizer, and three rows do not. She
  counts and compares the number of beans from each
  set of bean plants and discovers that the
  fertilized plants produce 50 more beans than the
  unfertilized plants.

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Example (continued)

• What was the purpose of the experiment?
• To find out if fertilizer will make beans grow
  better
• What was the hypothesis?
• Fertilized bean plants will produce more beans
  than unfertilized bean plants.
• What was the independent variable?
• Amount of fertilizer
• What was the dependent variable?
• Number of beans

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Example (continued)

• What were the control group and the experimental
  group?
• Control unfertilized plants
• Experimental fertilized plants
• What were some of the control variables?
• Number of plants per row, space between plants,
  light, water, soil, etc.
• Did the results support the hypothesis?
• Yes