Biology
The study of life

How do we distinguish between living and non-living things?

Living Things Share All These Attributes:

1.  Metabolism
Assimilate and use energy

2.  Response to stimuli in the environment

3.  Homeostasis
The maintenance of a relatively stable internal environment

4.  Inheritance
Possess an inherited information base, encoded in DNA, that allows them to function
DNA
Deoxyribonucleic acid
? The primary information-bearing molecule of life
Proteins (more specifically, enzymes) are put together in accordance with the information encoded in DNA.
? Composed of two chains of nucleotides, bonded at their nitrogen bases in the form of a double helix

 5.  Composed of one or more CELLS:
Cells are the basic units of life—they carry out all the functions of living things.  They are the smallest biological units considered to be alive.

6.  Growth & Development

7.  Reproduction
Reproduce through use of the information encoded in DNA

Sexual Reproduction
There is an exchange of genetic information when cells from two parents combine to form the first cell of a new individual.

Asexual Reproduction
In which a single organism produces offspring identical to itself.

Binary fission
In which one cell divides into two identical daughter cells.
Used by bacteria, archaea, and the organelle mitochondria.

8.  All living things have evolved from other living things

Evolution is Biology’s Chief Unifying Principle

Evolution
The gradual modification of populations of living things over time, with this modification sometimes resulting in the development of new species.

Evolution is central to biology because every living thing has been shaped by it.

? All aspects of nature’s diversity can be explained in terms of evolution.

9.  All living things are highly organized compared to inanimate objects

Life is Highly Organized in a Hierarchical Manner

Levels of Organization in Living Things

1. Atoms
2. Molecules    Non-living
3. Organelles

4. Cells
5. Tissues
6. Organs
7. Organ Systems
8. Individuals
      Living things
9. Populations
10. Communities
11. Ecosystems
12. The Biosphere (Earth)

 Review Questions

What is biology?

Name nine characteristics that distinguish living things from non-living things.

What is metabolism?

What is homeostasis?

What is the difference between sexual and asexual reproduction?

What is binary fission?

What is DNA?
What is the structure of DNA?

Name and define the chief unifying principle of biology.

What theory explains nature’s diversity?

Starting with the basic unit of life, what are eight levels of organization in living things, from most simple to most complex?
 
 

?
 

REVIEW & DO NOW Answer the following questions:
?	?

Organization & Classification of Living Things

Taxonomy
Classifying organisms according to similarities in patterns of embryological development and adult anatomical and physiological characteristics

The Eight Taxons—levels of classification—are:
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
Domain
All life is grouped into three main categories—Domains
Bacteria Archaea Eukarya

All eukaryotic have their DNA in a membrane-bound nucleus.

Kingdom
Domain Eukarya is grouped into four Kingdoms
? Protista ? Animalia ? Fungi ? Plantae

Each kingdom is further divided into groups called phyla.

Phylum
Within Kingdom Animalia there are 35 total phyla, 
with nine of them being the most well known and understood, including

? Porifera—the sponges
? Cnidaria—corals, sea anemones, and jellyfish
? Platyhelminthes—flatworms, including tapeworms
? Nematoda—roundworms, parasitic in animals or plants, or free-living in soil or water
? Annelida—segmented worms, including earthworms & leeches
? Mollusca, second largest invertebrate phylum, including snails, clams, octopuses, & squids
? Arthropoda—largest invertebrate phylum, segmented body, jointed appendages, chitinous exoskeleton, including insects, arachnids, mites, lobsters, crabs, & shrimp
? Echinodermata, including sea stars (starfish), sea urchins, & sea cucumbers
? Chordata, including subphylum Vertebrata—animals with a brain, a skull, & a backbone

Class
Subphylum Vertebrata (in Phylum Chordata) can be divided into five extant (and one extinct) classes:
(in order of evolution)
? Fish (Osteichthyes)—lay eggs in water
? Amphibians—lay eggs in water—frogs, toads, salamanders
? Reptiles—lay hard-shell eggs on land, have scales—snakes, lizards, turtles, alligators & crocodiles
? Dinosaurs (extinct)—laid hard-shelled eggs on land in nests—including T-Rex, pterodactyls, brontosaurus, & triceratops
? Avians—birds—lay hard-shelled eggs in nests, have feathers, many can fly
? Mammals—live birth, nurse their young with milk from mammary glands, have hair or fur, & heterodant dentition

Order
A group of related families belonging to the same class
There are 19 mammalian orders, including
? Artiodactyla (even-toed hoofed animals), including giraffes, deer, pigs, cattle, goats, sheep, hippopotamuses, camels & llamas
? Perissodactyla (odd-toed hoofed animals), including horses, zebra, & rhinoceroses
? Carnivora (meat eaters), including dogs & wolves, bears, raccoons, cats of all sizes,
? Cetacea (including whales & porpoises)
? Chiroptera (bats)
? Lagomorpha (including hares & rabbits)
? Primata (including shrews & lemurs, monkeys & apes)

Family
Members of the same order which share common characteristics, attributes, & qualities
Families in Order Carnivora include
? Canidae—the canines, including wolves, dogs, foxes, & coyotes
? Felidae—the felines, including lions, tigers, panthers, & cats
? Ursidae—the bears

Genus & Species
In taxonomy, a genus is a group of closely related species in the same family.
A species is a group of members of the same family that can interbreed and produce fertile offspring.

Members of the same species are usually indicated through binomial nomenclature—
? a two-part name where 
? the genus is capitalized, 
? the species is all-lowercase, 
? entire name is italicized if typed or underlined if handwritten.

Species name of dog—Canis familiaris 
or Canis lupus familiaris (trinomial nomenclature)

Wolf
Canis lupus

Coyote
Canis latrans

Cat
Felis catus
Felis domesticus

Tiger
Panthera tigris

Lion
Panthera leo

Western gorilla
Gorilla gorilla

Black bear
Ursus americanus

Polar bear
Ursus maritimus

 Population
A group of individuals of the same species living in the same area.

Example:
The population of Albuquerque
The population of roadrunners in Albuquerque
A colony of the Clostridium tetani bacteria living in a cut on your foot

Community
A group of diverse populations living in the same area

Example:
The wildlife of the Bosque, including coyotes, turtles, ducks, & porcupines

Ecosystem
All the communities of an area, including their nonliving environment

Example
A swamp, a forest, a lake, or a prairie, and all the animals there

Biome
A group of ecosystems that share similar climate and populations

Example
The Chihuahuan desert in southern New Mexico, with its dry climate, extreme temperature changes, sandy soil, mesquite, sage, prickly pear cactus, yucca, ants, rattlesnakes, roadrunners, quail, jackrabbits, & coyotes

 Review Questions

What are the eight levels of classification in taxonomy?

What are the three Domains of Life?

What are the four Kingdoms of Life in Domain Eukarya?

What Kingdom would a dog and an ant belong to?

What phylum (or subphylum) would a dog and an ant belong to?

What are the five extant and one extinct classes of vertebrates—in order of evolution?

What class do dogs and humans belong to?
What are three characteristics all members of this class share?

What is a population?
Give an example.

What is a community?

What types of animals would you find in a river ecosystem, including the river itself and grassy banks and trees growing along the edge?

What would be the differences in a desert biome, such as Arizona, and a tropical rain forest, such as northwestern Brazil?
 
 

?
 

REVIEW & DO NOW Answer the following questions:
?	?