Biology 1

Ø Lecture Monday through Thursday: 11:30 AM – 1:40 PM MTSC Room 401

Dr. Rana Tayyar

Ø Lab MTSC Room 303

Monday-Thursday AM (Section 41137): 9:00-11:10 AM Monday-Thursday PM (Section 41139): 2:00-4:10 PM

Ø Office hours By appointment only

Syllabus http://websites.rcc.edu/tayyar/

Syllabus Ø Objectives of the course

Ø Grading

Ø Exam policies

Ø Classroom policies

Ø Attendance: Mandatory

Succeeding In This Class

Ø Take your school work seriously

Ø Come to class prepared

Ø Attend all lectures

Ø Be an active participant

Succeeding In This Class Ø Allow some “biology” time every day Ø Read your notes and rewrite them (within

24 hours is best) Ø Please read the textbook Ø Prepare flash cards Ø Form study groups Ø Discuss any questions with me Ø Come to office hours Ø Tutorial Services: MLK Bldg., Room 232

Invitation to Biology

Biology Ø Bios = life (from

Greek)

Ø -logy/-ology = scientific study of a subject

Ø Biology = scientific study of life

The word science is derived from a Latin word “scire” meaning to know

Science: The systematic study of the observable world and how it works

Critical thinking is a big part of science judging information before accepting it

Scientific Method

Ø Is not a rigid procedure

Ø Based on evidence to logically solve problems and answer questions

Process consisting of a series of steps used to answer questions

Steps of the Scientific Method

Hypothesis: testable explanation of a natural phenomenon

Prediction: statement, based on a hypothesis, about a condition that should exist if the hypothesis is correct

Independent variable: condition or treatment controlled by the experimenter

Variable: a characteristic or event that differs among individuals or over time

Experiment: test designed to support or falsify a prediction

Dependent variable: observed result that is influenced by the independent variable

Control group: identical to an experimental group, but without exposure to the independent variable

Experimental group: receive a certain treatment or have certain characteristics

Sample size and replications

Butterflies and Birds Ø Researchers investigated whether certain peacock

butterfly behaviors defend them against predatory birds

Initial observations: When a peacock butterfly rests, it folds its wings, so only the dark underside shows When a butterfly sees a predator approaching, it flicks its wings open, producing a hissing sound and a series of clicks

Ø First hypothesis: wing-flicking exposes brilliant spots that resemble owl eyes

Ø Second hypothesis: hissing and clicking sounds may be an additional defense that deters predatory birds

Ø Experimental design:

Ø Paint the wing spots of some butterflies black

Ø Remove sound-making wing part of others

Ø Place butterfly into cage with a hungry blue tit

Ø Observe for 30 minutes

Ø Conclusions:

Ø The test results supported the hypotheses Ø Predatory birds are indeed deterred by

peacock butterfly sounds, and even more so by wing spots

Inductive reasoning: drawing a conclusion based on many specific observations

Deductive reasoning: using a general idea to make a conclusion about a specific case

Sampling error

More Terms relating to scientific inquiries

Probability Statistically significant Scientific Theory Law of nature

Observations

Question

Hypothesis # 1: Dead batteries

Hypothesis # 2: Burnt-out bulb

Prediction: Replacing batteries will fix problem

Prediction: Replacing bulb will fix problem

Test prediction Test prediction

Test falsifies hypothesis Test does not falsify hypothesis

Science addresses only testable ideas about observable events and processes It does not address anything untestable, such as beliefs and opinions

Limitations of Science

Forms of Life Share Common Properties

Ø Order Ø Use of DNA as hereditary material

during reproduction Ø Growth and development Ø Energy Processing Ø Response to stimuli Ø Homeostasis Ø Evolutionary adaptation

Order Living organisms are both complex and organized

A Closer Look at Biological Organization

Life organization extends from the microscopic scale of atoms and molecules to the global scale of the biosphere

Ø Atom Ø Molecule/ Biological

Molecules Ø Organelle/Cell*

§  Cells are the fundamental units of life

Ø Tissue Ø Organ

A Hierarchy of Biological Organization

Ø Organ system Ø Organism (Beyond the level of

organisms) Ø Population Ø Community Ø Ecosystem*

§  Producers §  Consumers §  Decomposers §  Physical environment

Ø Biosphere

New properties that arise in each step upward in the hierarchy of life as a result of interactions between components and proper arrangement of components

“An organism is a living whole greater than the sum of its parts”

Emergent Properties

Energy Processing

2) How do organisms obtain energy? Ø  Producers Ø Consumers

1) Why do organisms need energy?

Ø  Power activities and chemical reactions

producer acquiring energy and nutrients from the environment

consumer acquiring energy and nutrients by eating a producer

3

ENERGY IN SUNLIGHT

Producers harvest energy from the environment. Some of that energy flows from producers to consumers.

Nutrients that get incorporated into the cells

of producers and consumers are eventually released back into

the environment (by decomposition, for example). Producers then take up some of the

released nutrients.

4

plants and other self-feeding organisms PRODUCERS

animals, most fungi, many protists, bacteria CONSUMERS

5 All of the energy that enters the world of life eventually flows out of it, mainly as heat released back to the environment.

Cycling of chemicals from the atmosphere and soil through producers, consumers and decomposers back to the environment

Energy flow: Sunlight Producers Consumers

Response to Environment Response to a stimulus

Homeostasis

Living organisms have the ability to maintain a stable internal body environment even in the face of a fluctuating external environment

Living Organisms Use DNA Ø DNA (deoxyribonucleic acid) carries hereditary

information that guides: Ø Development: multistep process by which the

first cell of a new multicelled organism gives rise to an adult

Ø Growth: increase in the number, size, and volume of cells

Ø Reproduction: processes by which individuals produce offspring

Ø Inheritance: transmission of DNA to offspring Ø All organisms inherit their DNA from one or

two parents Ø DNA is the basis of similarities in form and

function among organisms: All forms of life use the same genetic code to translate the information stored in DNA into proteins

Ø Small variations in DNA give rise to differences among individuals and among types of organisms

The Diversity of Life

Taxonomy (Carolus Linnaeus) Science that deals with the identification and the classification of living organisms

Ø Domain Ø Kingdom Ø Phylum Ø Class Ø Order Ø Family Ø Genus Ø species

Taxonomic Classification

Species: unique type of organism Biological species concept Trait: an observable characteristic of an organism or species (morphological, molecular) Taxon: group of organisms that share a unique set of traits

The Three Domains The diversity of life can be arranged into three domains:

Ø Archaea

Ø Bacteria

Ø Eukarya

Bacteria Archaea Protists Plants Fungi Animals

Bacteria Archaea Eukarya

Kingdoms

Domains

Domain Archaea Archaea are prokaryotes that often live in Earth’s extreme environments

Domain Bacteria Bacteria are the most diverse and widespread prokaryotes

Domain Eukarya All members have eukaryotic cells

Ø Protists Ø Fungi

Ø Plants Ø Animals