1. Introduction to Biology
Studying Life’s Diversity and Intricate Processes

2. Biological Inquiry Bio = of living things
Biological Science: observation, identification, experimental investigation and theoretical explanation of natural phenomena
What are the Characteristics of Living Things?
What are Fundamental Concepts that Relate to these Characteristics?
How Do Biologists Study Living Things?

3. What are common characteristics of living things?
Properties of Life
organization involving cells
energy use and metabolism
response to environmental changes
regulation and homeostasis
growth and development
reproduction
biological evolution

4. Concept: New Properties Emerge at Each Level in the Biological Hierarchy
Principle of Emergent Properties
New characteristics arise out of the arrangement and interactions of the components of a complex system (whole > sum of the parts)
organization

5. Organizational Hierarchy of Life
Most Complex
Least Complex
biosphere
inhabitable regions of earth
ecosystem
coral reef (living + nonliving)
community
coral reef populations
population
school of fish
organism
fish
organ system
nervous system
organ
brain
tissue
nervous tissue
cell
neuron
organelle
nucleus
macromolecule
DNA
molecule
nucleotide
atom
nitrogen
sub-atomic particles
protons, neutrons, electrons

6. Concept: Cells are an Organism’s Basic Units of Structure and Function.
Two types of cells
Prokaryotic
Archaea and Bacteria
few internal membranes
no membrane-bound nucleus
Eukaryotic
Protists, Fungi, Animals, Plants
extensive internal membranes
membrane-bound nucleus
organization

7. Concept: Structure and Function are Correlated at all Levels of Biological Organization.
How is red blood cell structure suited to its function of carrying oxygen?
organization

8. Energy Use and Metabolism
Energy = ability to do work
Energy conversion = change of one form of energy to another
Metabolism = sum of chemical reactions in an organism
Heterotrophic: other feeder
taking in organic molecules produced by other organisms
Autotrophic: self-feeder
photosynthesis = using the energy of the sun to produce organic molecules

9. reproduction regulation
Concept: The Continuity of Life is Based on Heritable Information in DNA.
The molecule of heredity = DNA = deoxyribonucleic acid
reproduction regulation

10. Genomes and Proteomes reveal evolutionary relationships
Per 23 chromosomes
Now estimated at 30,000 genes
Proteome: all proteins produced in a cell or organism
Genome: complete genetic composition of an organism
Genomes and Proteomes reveal evolutionary relationships

11. Nuclear division retaining the original chromosome number
Concept: The Continuity of Life is Based on Heritable Information in DNA.
Nuclear division retaining the original chromosome number
Nuclear division reducing the chromosome number, leading to sperm or eggs

12. growth and development
Concept: The Continuity of Life is Based on Heritable Information in DNA.
Growth = increase in size
Development = change in characteristics
growth and development

13. Concept: Feedback mechanisms regulate biological systems.

14. Concept: Feedback mechanisms regulate biological systems.
Living things maintain homeostasis = a relatively stable internal condition
regulation and homeostasis response to environmental changes

15. Plant Responses to Sunlight
Desert plant leaves
oriented vertically to minimize water loss
Alfalfa leaves oriented
toward sunlight to maximize photosynthesis
response to environmental changes

16. Concept: Evolution Accounts for the Unity and Diversity of Life
Two mechanisms of evolutionary change
Vertical Descent with Mutation: through changes in DNA, new species arise from pre-existing species
Natural Selection: individuals with traits that provide an advantage in the current environment are more likely to survive and reproduce
response to environmental changes
biological evolution

17. Concept: Evolution Accounts for the Unity and Diversity of Life
Vertical Descent with Mutation

18. Concept: Evolution Accounts for the Unity and Diversity of Life
Natural Selection leads to a change in the genetic characteristics of a population  evolution
Adaptation = characteristic that promotes survival and reproduction

19. The Unity and Diversity of Living Things
An Evolutionary Tree of Life
The Three Domains of Life Represent the Earliest Branches in Evolutionary History
Contains multiple kingdoms

20. How Do Biologists Study Living Things?
Discovery Science
Collect Data without a pre-stated hypothesis
Make Observations = objective notations of a phenomenon
Can lead to formulation of hypotheses
Example: determine how many amphibian species are present in a specific environment

21. How Do Biologists Study Living Things?
Hypothesis-based Science
Ask Questions or make Observations
Formulate an Hypothesis: tentative answer to well-framed question
Make Predictions based on hypothesis
Test Predictions by Conducting Experiments
Analyze experimental data
Determine whether data supports hypothesis
You Tube video on Paramecium contractile vacuole

22. How Do Biologists Study Living Things?
Biology 21 Definition
An Hypothesis will have
Two measurable variables
Precise relationship between them (relationship = prediction)
The relationship between DNA content and length of the cell cycle is a direct proportion.

23. How Do Biologists Study Living Things?
A good hypothesis is
Testable
experiments can be designed to test predictions from the hypothesis
experimental results must be repeatable
Falsifiable
allows scientists to eliminate alternative hypotheses

24. How Do Biologists Study Living Things?
Testing hypotheses
Controlled Experiment
test designed to determine the effect of one factor while keeping all other factors constant
experimental = sample treated to test for effect of the factor being studied
control = sample treated like experimental in all ways EXCEPT for the factor being studied

25. Use of a Controlled Experiment
Increasing dose of almonds on subjects with hyperlipidemia.
Full almond = 73 grams/day
Control = whole wheat muffins (>5% saturated fat)
Half almond = half dose almond + half dose muffins
All supplements provided equal amounts of energy in the diet.
Jenkins, et al., 2002, Circulation 106:1327
(Circulation. 2002;106:1327.)
Dose Response of Almonds on Coronary Heart Disease Risk Factors: Blood Lipids, Oxidized Low-Density Lipoproteins, Lipoprotein(a), Homocysteine, and Pulmonary Nitric Oxide
A Randomized, Controlled, Crossover Trial
David J.A. Jenkins, MD; Cyril W.C. Kendall, PhD; Augustine Marchie, BSc; Tina L. Parker, RD; Philip W. Connelly, PhD; Wei Qian, PhD; James S. Haight, MD; Dorothea Faulkner, RD; Edward Vidgen, BSc; Karen G. Lapsley, DSc; Gene A. Spiller, PhD
Background— Although recent studies have indicated that nut consumption may improve levels of blood lipids, nuts are not generally recommended as snacks for hyperlipidemic subjects because of their high fat content. Furthermore, the effective dose is still unknown.
Methods and Results— The dose-response effects of whole almonds, taken as snacks, were compared with low-saturated fat (<5% energy) whole-wheat muffins (control) in the therapeutic diets of hyperlipidemic subjects. In a randomized crossover study, 27 hyperlipidemic men and women consumed 3 isoenergetic (mean 423 kcal/d) supplements each for 1 month. Supplements provided 22.2% of energy and consisted of full-dose almonds (73±3 g/d), half-dose almonds plus half-dose muffins, and full-dose muffins. Fasting blood, expired air, blood pressure, and body weight measurements were obtained at weeks 0, 2, and 4. Mean body weights differed <300 g between treatments. The full-dose almonds produced the greatest reduction in levels of blood lipids. Significant reductions from baseline were seen on both half- and full-dose almonds for LDL cholesterol (4.4±1.7%, P=0.018, and 9.4±1.9%, P<0.001, respectively) and LDL:HDL cholesterol (7.8±2.2%, P=0.001, and 12.0±2.1%, P<0.001, respectively) and on full-dose almonds alone for lipoprotein(a) (7.8±3.5%, P=0.034) and oxidized LDL concentrations (14.0±3.8%, P<0.001), with no significant reductions on the control diet. No difference was seen in pulmonary nitric oxide between treatments.
Conclusions— Almonds used as snacks in the diets of hyperlipidemic subjects significantly reduce coronary heart disease risk factors, probably in part because of the nonfat (protein and fiber) and monounsaturated fatty acid components of the nut.

26. How Do Biologists Study Living Things?
Supported Hypotheses
Theory = broad explanation of a natural phenomenon that has been supported by a large body of evidence
Principle or Law = theory that has been supported over a long period of time
Cell Principle
All living things are composed of cells and cell products; all cells come from pre-existing cells.
Principle of Evolution
Principle of Emergent Properties