What is Biology?

Why do we study Biology?

How can we make learning biology (the study of living things) easier?

Classification

Science is tentative…

3 Domains of LifeArchaeEu karya

Bi nomial nomenclature• The 2 word naming system for

classifying living organisms. Written in Latin.

• “Scientific name”– Genus species (capitalized & lower case)– Homo sapiens or Homo sapiens

• What is the correct classification of the domestic dog?A. Canis Domesticus D. Canis domesticusB. Canis domesticus E. canis DomesticusC. Canis domesticus F. canis domesticus

Classification of Organisms• Biologists classify all organisms into large

categories called domains. There are 3 domains that are further classified into kingdoms

• A kingdom consists of a collection of closely related phyla (singular phylum).

• A phylum is a group of related classes.• A class is a group of related orders.• An order is a group of closely related families

having common characteristics.• A family is a group of closely related genera

(singular genus). Most genera are similar; some have noticeable differences.

• A genus is a group of closely related species. For example, the oak genus consists of pine oak, white oak, and many other oak species.

• Species is the basic (smallest) unit in the classification of organisms. It is a kind of organism, such as a dog or a sugar maple tree.

• Biologists do not agree on a single classification system. For example, some classify organisms into three, four, or five kingdoms.

What is a species?Species agroup of

organisms that can reproduce and have fertile offspring

What is a dichotomous key?

• Dichotomous keys are commonly used to determine the genus and species of a specimen.

• They are particularly useful when many species look alike.

Choose your own adventure…

• What would you do if…… your flight to Paris was taken over by hijackers?

• If you volunteer yourself to be their hostage in order to save the other passengers go to page 112

• Or if you wait to see what they would do go to page 239

Review

• Organization is the systematic grouping of things to show interrelationships.

• To develop an organizational outline, start with the largest category and subdivide into smaller categories.

• Classification, or taxonomy, is a systematic arrangement of organisms into categories based on their characteristics and interrelationships.

• Classification simplifies the identification and study of organisms according to their characteristics.

Select The Letter Of The Correct Answer From The List Below:

A. species D. Category G. Domain

B. class E. genus

C. Kingdom F. Taxonomy

1. The largest category of classification is called a _________________.

2. A system of classifying organisms is called _________________.

3. The most specific category for classifying an organism is a ________________.

4. In any organizational plan, start with the largest _________________.

Review

Domain Eu karya

Kingdom Major Characteristics

Animal Ingestive hetero trophic, multicellular, lack cell walls and chlorophyll.

Plant Usually auto trophic, cell walls (cellulose), can be multicellular/unicellular.

Protist Autotrophic/heterotrophic, usually unicellular, some form colonies, some have cell walls (pectin).

Fungi Absorptive heterotrophic, lack chlorophyll, have cell walls (chitin).

BacteriaArchae

Eukarya

BacteriaArchae

Eukarya

All Domains

All living organisms

All have the 10 COL

Susceptible to viruses

Extremophiles

“ancient” organisms

Most closely related to Eukarya

All unicellular

Bacteria

Formerly known as Monerans

Prokaryotes

Common ancestor 3.5bya

Circular chromosome

Human beings

All eukaryotic: membrane bound organelles

4 Kingdoms: protista, fungi, animalial, plantae

Visible with naked eye

Can be multicellular

Usually live on and in human body

Cell walls of peptidoglycan

Growth inhibited by antibiotics

Grow best at “body” temperatures 37oC

Membranes have unbranched hydrocarbons

Found in nonextreme environments

Most closely related to each other

Common ancestor more recent than 3.4bya

Cladogram-a branching tree used to illustrate phylogenetic relationships

1. Which 2 organisms separated the longest ago? Shark and ornithischian

2. What is the closest “relative” to a human on this cladogram? Wha

le3. What do you think the red dots

on the cladogram represent? They are extinct

4. Which 2 groups separated earlier: tuna and ornithischian or bird and sourischian? tuna and ornithischian

5. Which is less related: a whale and a crocodile or the crocodile and ornithischian? whale and a crocodile

1. Which 2 organisms are the most related? B & C

2. How long ago did A & D split? 3 mya

3. Which organism is most related to G? F

4. Which 2 organisms are the LEAST related? A & G

5. Which 2 organisms are MORE related: D & E or E & G? E & G

6. Which 2 organisms are LESS related: A & D or D & F? D & F

7. Which 2 organisms split 8 mya? A & G