The Tree of Life: 2011

Monday, January 31, 2011

Works Cited

Saturday, January 29, 2011

Kingdom Animalia

Describe:

Animals are made up of cells that do not have cell walls.
Animals are capable of motion in some stage of their lives.
Animals are able to respond quickly to external stimuli as a result of nerve cells, muscle or contractile tissue, or both.

Body Plan:

multicellular

Divergent Event:

it is believed animal kingdom diverged from fungi kingdom

Metabolism:

heterotrophic

Digestion:

both intracellular and extracellular

For example, in the phylum Porifora -which contains animals like sponges - uses intracellular digestion. This is when food is digested in each individual cell.
Other more complex animal use extracellular digestion. This is when nutrients are digested in other digestive cavities then distributed throughout the body.

Circulation:

both closed and open

Mollusks have an open circulatory system, though some do have a closed system.
the phylum Annelid, has a closed system, where the aortic valve arches to replace the heart.

Respiration:

cellular respiration; gills book lung and lungs

Nervous:

Most animals have a central nervous system

a brain which is attached to the rest of the body through a spinal cord

Reproduction:

sexually and asexually

asexually - komodo dragons
sexually - rabbits

Examples:

eagles
dogs
squirrels

Phylum Porifera

Describe

No definite symmetry. Cells and tissues surround a water filled space but there is no true body cavity.
Body multicellular, few tissues, no organs.
All are sessile, (live attached to something as an adult).
Reproduce sexually or asexually, sexual reproduction can be either gonochoristic or hermaphroditic.
Has no nervous system.
Has a distinct larval stage which is planktonic.
Lives in aquatic environments, mostly marine.
All are filter feeders.
Often have a skeleton of spicules.

Examples

Ephydatia fluviatilis

Phylum Annelida

Describe -

Bilaterally symmetrical and vermiform
Body has more than two cell layers, tissues and organs
Body cavity is a true coelom, often divided by internal septa
Body possesses a through gut with mouth and anus
Body possesses 3 separate sections, a prosomium, a trunk and a pygidium
Has a nervous system with an anterior nerve ring, ganglia and a ventral nerve chord
Has a true closed circulatory system
Has no true respiratory organs
Reproduction normally sexual and gonochoristic or hermaphoditic
Feed a wide range of material
Live in most environments

Examples -

Chaetogaster annandale -smallest Annelid known to science is which is full grown at 0.5 mm (0.02 ins)

Phylum Mollusca

Describe -

Bilaterally symmetrical.
Body has more than two cell layers, tissues and organs.
Body without cavity.
Body possesses a through gut with mouth and anus.
Body monomeric and highly variable in form, may possess a dorsal or lateral shells of protein and calcareous spicules.
Has a nervous system with a circum-oesophagal ring, ganglia and paired nerve chords.
Has an open circulatory system with a heart and an aorta.
Has gaseous exchange organs called ctenidial gills.
Has a pair of kidneys.
Reproduction normally sexual and gonochoristic.
Feed a wide range of material.
Live in most environments.

Example

scallops

snails

Phylum Chordata

Subphylum Vertebrata

Describe -

possession of a set of vertebrae
skin is normally comprised of two sections; the outer epidermis which is secreted by the ectoderm and an inner endodermis which is secreted by the mesoderm.,
normally have a closed circulatory system (veins and arteries) with a heart of 2,3, or 4 chambers
most, if not all vertebrates have an endocrine system
a complicated nervous system
separate sexes
complete digestive system with well developed associated glands such as the liver and pancreas ventral to the spinal column and with a separate mouth and anus

Class Myxini

Describe

Hagfishes look like eels and are about 18–30 inches (46–76 centimeters) long
skeleton is made up of cartilage , or tough, bendable tissue, rather than bone.
no fins or scales—flat, rigid plates that act as body covering.
They do not have jaws but have two raspy, or rough, biting plates.
The mouth is an oval slit surrounded by four barbels , which are long, thin feelers used for finding food.
The single nostril is surrounded by another set of barbels. The eyes are two dents on the top of the head that are covered by skin, and the fishes probably cannot see with them.
Hagfishes have six to ten pairs of gills, or breathing organs, which may open directly to the outside or join to form one gill opening.
The color of hagfishes ranges from reddish brown to grayish pink.
Hagfishes have about 100 to 150 slime glands along the sides of their bodies. Defense - themselves by producing slime.
live in large groups on the ocean floor.
Reproductive patterns are unknown. Fertilization is probably external.

Example -

Sixgill hagfish

Class Cephalospidomorphi

Describe -

jawless fish, whose adults are characterized by a toothed, funnel-like sucking mouth.
Found in most temperate regions except those in Africa.
Adults physically resemble eels, in that they have no scales, and can range anywhere from 13 to 100 centimetres (5 to 40 inches) long.
unique morphological characteristics of lampreys, such as their cartilaginous skeleton

Example

sea lampreys

Class Chondricthyes

Describe -

jawed fish with paired fins, paired nares, scales
two-chambered hearts
skeletons made of cartilage rather than bone

Example -

great white shark

Class Osteichthyes

Describe -

characterized by a relatively stable pattern of cranial bones, rooted teeth, and medial insertion of mandibular muscle in lower jaw
The head and pectoral girdles are covered with large dermal bones
The eyeball is supported by a sclerotic ring of four small bones, but this characteristic is missing or modified in many modern species

Example -

catfishes

Class Amphibia

Describe -

cold-blooded or ectothermic animals
start their life cycle underwater and move to land on the onset of their adulthood
Generally carnivorous; while in water, consume a wide variety of fish, small reptiles, crustaceans and other amphibians
most amphibians breed in freshwater, there are some species that breed in moist places , ex: burrows in the ground and among leaf litter or in wild habitats

Examples

salamander

Class Reptilia

Describe -

A tough, dry, scaly skin that is heavily keratinized

Keratin- a resistant protein found in the epidermis of amniotes
protective and prevents water loss across body surfaces
Human hair and nails are made of keratin

Few cutaneous (skin) glands are present
The body is covered and protected by scales and scutes
A strong, sturdy skeleton with a well-developed rib cage
Large well-developed lungs

Example –

alligator

Class Aves

Describe -

highly adapted for flight although many species have lost the powers of flight
They have scaly legs and feathers (which are specialized scales)
They are toothless animals, but have a beak

Example –

hummingbird

Class Mammalia

Describe-

characterized by the possession of hair, three middle ear bones, a neocortex, and mammary glands functional in mothers with young
Most posses sweat glands and specialized teeth

Example –

cat

Friday, January 28, 2011

Kingdom Plantae

Describe:

eukaryotic
perform photosynthesis
have chlorophyll
cells walls made of cellulose

Body Plan:

muticellular

Divergent Event:

scientists believe land plants evolved from green algae

Metabolism:

autotrophic

Digestion:

none

Circulation:

only some plants have circulatory systems- vascular plants
no heart

Respiration:

the chemical opposite of photosynthesis - it releases energy, using up food and oxygen and producing carbon dioxide
the release of energy from food

Nervous:

none

Reproduction:

both sexual and asexual

Sexual - roses
asexual – maple tree

Examples:

Moss
Shrubs

Phylum Cycadophyta

Describe

Dioecius
Tropical and sub-tropical habitats
Pachycaul stem
Girdling leaf traces
Coralloid roots
Lack axillary buds
Open carpophyll
Woody, long-lived, unisexual plants. Main roots thickened, fleshy, often tuberous

Environment -

Tropical and subtropical latitudes in the Americas, Caribbean, sub-Saharan Africa, Madagascar, eastern India, China, Japan, southeast Asia, Oceania and Australia.

Examples -

Cycas rumphii

evergreen

Phylum Gingkophyta

Describe -

distinctive fan shaped leaves & are dioecious (each tree is either male or female but not both)

Enviroment -

not native to North America (they are found growing wild only in China)

Examples -

Ginkgo biloba tree

Phylum Anthopyta

Class Monocotyledonae

Describe -

comprising seed plants that produce an embryo with a single cotyledon and parallel-veined leaves
includes grasses and lilies and palms and orchids
divided into four subclasses or superorders: Alismatidae; Arecidae; Commelinidae; and Liliidae

Example -

Hemerocallis flower

Class Dicotyledonae

Describe -

comprising seed plants that produce an embryo with paired cotyledons and net-veined leaves

Example –

beans

ground nut

Thursday, January 27, 2011

Kingdom Archaea

Describe:

group of single-celled microorganisms
Similar to bacteria in size and shape though a few have very strange shapes.
commonly as spheres, rods, spirals or plates.
Individual archaea range from 0.1 micrometers (μm) to over 15 μm in diameter

Body Plan:

unicellular

Divergent Event:

may be the most ancient lineage on earth.
The oldest traces of archaen lipid remains come from the Isua district of west Greenland including Earth's oldest sediments - formed 3.8 billion years ago

Metabolism:

Both

autotrophic - Nitrosopumilales
heterotrophic - Thermococcus fumicolans

Digestion:

intracellular

Circulation:

none

Respiration:

none

Nervous:

none

Reproduction:

Asexual

divide by binary fission, fragmentation or budding

Examples:

Sulfolobus acidocaldarius - found near volcanic environments in hot, acidic springs containing sulfur

Pyrolobus fumarii - live in temperatures between 90 and 113 degrees Celsius

Kingdom Eubacteria

Describe:

large group of unicellular organisms
Typically a few micrometres in length
wide range of shapes, ranging from spheres to rods and spirals

Body Plan:

unicellular

Divergent Event:

ancestors of modern bacteria - single-celled microorganisms that were the first forms of life to develop on earth about 4 billion years ago.
Here eukaryotes resulted from ancient bacteria entering into endosymbiotic associations with the ancestors of eukaryotic cells- which were themselves possibly

Metabolism:

both

autotrophic – cyanobacteria
heterotrophic - E. Coli

Digestion:

intracellular

Circulation:

None

Respiration:

None

Nervous:

None

Reproduction:

asexual

Examples:

Lactobacillus acidophilus – found in dairy products, Nitrogen Fixing Bacteria

Cyanobacteria

E. Coli