Classification. Taxonomy: the science of classification. Why do we classify organisms?. 1. Why Classify? To study the diversity of life To group organisms according to shared lines of evolutionary descent 2. Why are organisms given scientific names? Common names are misleading.
Taxonomy: the science of classification
Why do we classify organisms?
2. Why are organisms given scientific names?
None of these animals are fish!
Why Scientists Assign Scientific Names to Organisms?
Scientific name: Felisconcolor
Scientific name means “coat of one color”
“Homo” is the Genus, “sapiens” is the species.
(Ex. H. sapiens)
King Philip came over for good sweets!
Hierarchical Ordering of Classification
As we move from the kingdom level to the species level, more and more members are excluded – species is least inclusive!
SPECIES Ursus arctos
The root of the tree represents the ancestral lineage, and the tips of the branches represent the descendents of that ancestor. As you move from the root to the tips, you are moving forward in time.
When a lineage splits (speciation), it is represented as branching on a phylogeny. When a speciation event occurs, a single ancestral lineage gives rise to two or more daughter lineages.
Here's an example in written form using these items:
1. Virus attaches
2. Virus injects genetic information into host
3. New viral proteins and genetic material are made
4. Viral parts are assembled
5. New viruses are released as host cell lyses (bursts) and is destroyed.
Lytic and Lysogenic Cycles of Reproduction
(2) type of cell wall
(3) how they use energy
Bacteria that are spherical shaped are called coccus (cocci)
Bacteria that are rodlike are called bacillus (bacilli)
Bacteria that are spiral shaped are called spirilli
Identifying the type of cell wall using a technique known as Gramstainingis important for diagnostic and treatment purposes.
a. Gram positiveabsorbs the dye and look purple
b.Gram negativerepels the dye (has a capsule) and look pink
Kingdom Archaebacteria: Live in Extreme Habitats
Bacillus infernus lives in deep sea vents in the ocean – obtains energy from Earth’s heat
Slide # 9
Colonies of halophiles form a purple-red scum in these salt collection ponds of the Dead Sea
Colorful thermophiles grow in this hot spring.
Grand Prismatic Spring,
Yellowstone National Park, Wyoming Adam Jones
E-coli bacteria (yellow) on the head of a needle.
Bacteria are everywhere!
On all surfaces, in liquids, in air, etc
Thankfully most are harmless!
RED TIDE – caused by dinoflagellates
Texas gulf red tide – kills fish; latest affect on oyster harvesting
Called Fungus-like because they are heterotrophic and absorb nutrients from dead organic matter in a way similar to Fungi and lack chitin in their cell walls.
* Acellular slime mold
Harmful Effects of Fungi
Examples of fungal diseases of plants: Wheat Rust (left), ergots on rye (right)
2. Fungi will spoil food.
Rhizopus - common bread mold
3. Fungi cause Human Diseases:
Bacteria Free Zone
* Penicillin mold produces an antibiotic that destroys bacterial cell walls.
Helpful to Humans
2. Some are edible: some mushroom caps, morels, and truffles
Pigs are used to smell out truffles
Helpful to Humans
Fungi are also helpfulto the Environment!
1. Fungi are decomposers,
recycling organic matter.
2. Lichen – has a symbiotic relationship (mutualistic) Fungus + Algae. - Fungus gets food from the algae -The algae get water and minerals from fungus
3. Mycorrhizae – a symbiotic relationship (mutualistic) Fungus + Plant roots. Fungal hyphae extend into the soil and root, helping the plant absorb nutrients. Plant provides the fungi with the products of photosynthesis
The last 2 roots on the far right do not have mycorrhizae.
Plant roots covered with fungal hyphae which increases surface area for absorption.
Bilateral Symmetry – one plane of symmetry; definite right and left sides
no front or back; no right or left side
Radial Symmetry body parts repeat around the center
Coelom – a fluid-filled body cavity that is lined with tissue derived from mesoderm.
Sponges: asymmetry & acoelomate
Cnidaria(jellyfish/coral/anemones): radial & acoelomate
These sea anemones are feeding on a jellyfish.
Lion’s mane jellyfish
Elephantiasis caused by filarial worm in lymph nodes
African Guinea Worm
Many roundworms such as filarial worms, hookworms, and ascaris are parasitic and cause human diseases.
http://player.discoveryeducation.com/index.cfm?guidAssetId=A5FABC2E-807C-4804-9078-506E818A5E07&blnFromSearch=1&productcode=US (insects) 1:14
Echinoderms(starfish/ sand dollar/sea urchin): radial & coelom & acoelomate
Four structural characteristics set chordates apart from all other phyla:
a hollow dorsal nerve cord
a notochord (provides support (it acts like our backbone) and increases swimming efficiency)
a pharyngeal gill slits (respiratory structures)
postanal tail (follow the anus with a tail of variable length -again, an adaptation for locomotion).
These attributes are always found in the larval forms or early embryo (although they may be absent in the adult).
http://player.discoveryeducation.com/index.cfm?guidAssetId=5A1EACD2-3483-41F0-86B1-47B8300065E0&blnFromSearch=1&productcode=US (fish intro)
Class Agnathans(jawless fish)
Class Chondrichthyes(cartilaginous fish)
Class Osteictheys(bony fish)
Leafy Sea dragon
Chimaeras are known as ghost sharks because they live between 660 ft and 8,500 ft below the ocean floor!
A shark goes through 20,000 teeth in its lifetime!!
A skate is shown in the top picture with a stingray below
Examples: frogs, newts, salamander
http://player.discoveryeducation.com/index.cfm?guidAssetId=9AF59819-F781-462B-822B-8FDA4BEB534D&blnFromSearch=1&productcode=US (life intro)
http://player.discoveryeducation.com/index.cfm?guidAssetId=9AF59819-F781-462B-822B-8FDA4BEB534D&blnFromSearch=1&productcode=US (pebble frog)
http://player.discoveryeducation.com/index.cfm?guidAssetId=9AF59819-F781-462B-822B-8FDA4BEB534D&blnFromSearch=1&productcode=US (Basilisk Lizard)
Green Sea Turtles in Tortuguero
Snakes are carnivorous and stretch their jaws to consume their prey whole.
The sex of a crocodile is determined by temperature during wk 2-3 of the 2 mo. incubation, with females produced at 82-86 F, and males produced at 90 F and 93 F.
(Opp. for turtles)
Hollow bones for flight