Wednesday, February 23, 2011

Kingdom Animalia : Phyla

Today's schedule was going over the hydra and planarian lab, do pages 33-34 in the UP, and then notes.
Pages 33-34 was about a phylogenetic tree. *Animals on the outside are still living and animals that stop somewhere in the middle went extinct.

Embryonic development details:
Two branches for the animals with true coeloms:
  1. Mollusks, annelids, and anthropods- mouth comes first -- protostomes
  2. Echinoderms and chordates- anus comes first -- deuterostomes
Animalia Kingdom: 8 major phyla

Porifera- sponges
they are sessile;
simplest animals;
can be 1 cm or 2 m;
no nerves or muscles;
live in marine (salt water);
body is like a sace perforated with holes to let the water flow through;
digest food using phagocytosis;
eat bacteria from the water.
Cnidaria- jellyfish
have radial symmetry (more than one way to cut in half);
carnivores with stinging cells;
have a gastrovascular cavity (mouth and anus in one);
can be sessile (polyp) or free-floating (medusa).
Platyhelminthes- flatworms
bilateral symmetry (only one way to cut in half);
can live in marine, freshwater and even damp land;
can be parisitic (tapeworms);
no digestive tract in the parasites.
Nematoda- roundworms
most diverse animals known;
they live in wet soil and most aquatic habitats;
they have a completes digestive tract (mouth and an anus);
they are pseudocoelomates (body cavity partially lined with mesoderm;
can be very parasitic.
Mollusca- snails
soft bodied-usually with a hard protected shell;
feed using a straplike rasping organ called a radula;
can live in freshwater, marine, or land;
three main parts to the body-a muscular foot, a body mass with organs, and a drape-like mantle;
three major classes-gastropods (snails and slugs)
-bivalves (clams, oysters, and mussels)
-cephalopods (squids and octopuses)
Annelida- segmented worms
have body segementation (division on body into equal parts);
live in the sea, freshwater, and wet soil;
three major classes are earthworms, polychaetes, and leeches;
nourish the soil;
polychaetes are marine;
leeches have been used for medicine in the past.
Arthropoda- millipedes
have jointed appedages;
most successful phyla;
specialized functions: walking, feeding, sensory reception, copulation, defense, exoskeleton.
Echinodermata-seastars
HAVE NOT FINISHED THE NOTES ON THESE AS OF NOW.

The homework was UP pgs 37-38, prelab pgs 45-54, nature cover, and to read chapter 17
Next scribe: Skyler
( these were colorful but the color didn't work :[


Monday, February 21, 2011

2.18.11

Yunsu Y.


↑Parmecium ↑

Protists:
  • Most protists are single celled, but there are still some that are multicellular.

  • They are eukaryotes and more complex than prokaryotes.

  • 2 Theories of how eukaryotic cells evolved :


  1. All organelles evolved from inward folds of the plasma membrane or endocytosis. ----except mitochondria and chloroplast, because they have their own DNA.

  2. Endosymbiosis


  • developed by Lynn Margulis

  • chloroplast and mitochondria evolved from small prokaryotes that established residenc within other, larger host prokaryotes.----the host cell may have injested theses for food and if remained alive, continued to perform respiration within cell.



  • Like before, most are unicellular, but some are colonial or mulitcellular. (those two are different.)


  1. 4 categories of protists:


  • protozoans

  • slime molds

  • unicellular algae

  • seaweeds


  1. Protozoans


  • Ingest food and have to live in the water, wet soil or watery enviornment inside animals.

  • They have flagellates: one or more to move. Free living but some are parasitic

  • Amoeboas: move by pseudopodia-extensions of cytoplasm.

  • Forams: move with pseudopodia and components of limestone.

  • Apicomlexans: all parasitic and named for an apparatus at their apex.

  • Ciliates: use cilia to move and feed.

2. Slime molds:



  • may look like fungi but not closely related.

  • decomposers

3. Unicellular Algae:



  • have chloroplast

  • components of plankton-communities of organism, microscopic and drift or swim near surface of ponds and oceans.

  • planktonic algae=phytoplankton

  • 3 groups:
-Dinoflagellates: 2 flagella, blooms cause red tide.

-Diatoms: glassy cells walls with silica-used to make glass.

-Green algae: mostly in freshwater lakes and ponds. Most closely related to true plants but still towards the protists. Volvox is a colony of flagellated cells.



4. Seaweeds



  • multicellular marine algae

  • slimy rubbery substances that cushion bodies against waves

  • Different colors like: green, red, brown

  • Used fro food: found commonly in Asian food, soups, wraps, sushi.
-some have polysaccharides, humans cannot digest.



  • Also used for thickeners: pudding, ice cream, salad dressing, and Gel agar in petri dishes.


After notes we worked on U.P pg 27-31, whatever that was not finished was homework.

HW: pre-lab U.P pg 39-43, be prepared on Monday, know what we are doing. Nature Due 3/4



Next Scribe: Davin L.







Thursday, February 17, 2011

2.17.11

Kristen

Lab 44 and Fungi Notes

Today in class, we took notes on Fungus.

Some important things to remember.......

Fungi-

Decompose dead organisms
  • Recycle vital chemicals back into the environment
  • Eukaryotes
  • Multicellular
  • Heterotrophs
  • Some fungi is pathogenic
Structure and Function

  • Adapted for absorptive nutrition
  • Hyphae- threads composed of tubular walls
  • Hyphae form mycelium, which is the feeding network of a fungus



Reproduction

  • Reproduce by releasing spores
  • spores germinate to produce mycelia
Benefits

Eating
  • Yeast
  • Cheese
  • Delicacies
  • Antibiotics
  • Mycorrhizae
More detailed notes in note packet

We also did Lab 44

Objectives:

In this activity you will:

1. Identify the parts of a mushroom

2. Observe basidia and spores of a mushroom

3. Observe the structure of lichens


Materials:

  • mushroom
  • hand lens
  • paper
  • lichens

We did not do everything that the procedure said. Mrs. Andrews showed us what the different thinngs looked like under the microscope.


Lab 44 is in the workbooks


Homework:

Finish Lab 44
You Pick 2 UP pg 15-26 (pick to keys to do)

Next Scribe: Yunsu

Wednesday, February 16, 2011

Diversity

2/16/2011

Systematics- studying biological diversity(past and present) to reconstruct evolutionary history

Taxonomy- classification of species
-used to communicate internationally (common names for each species)
-international language-Latin

Carolus Linnaeus-physician and botanist who started Binomial nomenclature (two-part name for each species)
-Ex: Homo sapien (Genus capitalized, species lowercase, both in italics, or underlined if handwritten)

hierarchial classification system puts species into broader groups:
-Domain
-Kingdom
-Phylum
-Class
-Order
-Family
-Genus
-Species

Before, species were grouped by appearance
Now, "Cladistic Revolution" has taken place because of use of DNA, molecules, and technology
-classify species with Cladistic analysis- search for clades("branch" which consists of an ancestor and its descendants in a tree of life)
-items in a clade can be species, classes, phyla, etc.
-focuses on evolutionary innovations that define branch points in evolution
-let phylogeny (evolutionary history of a group or species) be discovered
-most used method in systemics

Cladistic Analysis is shaking phlyogenetic trees
-puts birds and reptiles in separate classes
-produces phylogenetic trees conflicting with classical taxonomy















Classification:
Old way: with 5 kingdoms
New way: with 3 domains
Bacteria (prokaryote)
Archaea (prokaryote)
Eukarya (eukaryote-plants, animals, fungi, protists)

Taxonomic Key- listing of specific characteristics, such as structure and behavior, in such a way that an organism can be identified
-has 2 opposing statements
-always start at statement number 1

Homework: UP 7-14
Next Scribe: Kristen M.

Sunday, February 13, 2011

Scribe Post: 2/14/11

TODAY, boys and girls, we finished our notes packet and worked on lab 32 in class (ooooooooooooooohhh) The notes taught us the names and characteristics of our evolutionary predecesor

  • Homo habilis- "handy man"- enlargement of brain, lived in east Africa
  • Homo erectus- extended territory to different parts of the world. Changes in diet included more meat consumption (from hunted animals), refined tools, taller, larger brain capacity (Thus more cognititve thought), lived in caves, built fires (hallelujah), social cooperation, African, Asian, European, and Austrailian.
  • Neandarthals- (descendents of H. erectus/ precursor to H. sapien)- Heavier browridges (sloped foreheads, similiar to gorillas), less pronounced chins, slightly larger brain size than us, skilled toolmakers, burials and rituals, abstract thought. Stereotypical "caveman", found in Europe, Middle East and Asia.
  • Homo sapiens- regionally diverse

- A.) Archiac Homo sapiens- oldest, over 300,000 years old, lived in Africa, Can include Neandarthals.

- B.) Cro-Magnon- like modern humans, lived in french caves (found cave drawings there), 35,000 years old.

- C.) Homo sapiens sapiens- Les humains modernes (modern humans :)

What happened to various H. Erectus descendents????

  • Multiregional hypothesis- Modern humans evolved simultaneously around the world. Genetic similiarities due to interbreeding with neighboring tribes.
  • "Out of Africa" hypothesis- (aka replacement hypothesis) Modern human arose from group in Africa and then spread around the world about 100,000 years ago. (Most widely accepted because of genetic backing)

Cultural Evolution-
  • Erect stance- Most radical change in our evolution. Required MAJOR realignment of pelvis, feet, and spine.
  • Enlargement of brain- secondary alteration-made possible by lengthened skull growth period. Accounts for lengthened parental care, and offspring learn from past generations.
  • Culture- transmission of accumulated knowledge by writing or storytelling.

- 3 MAJOR CULTURAL STAGES:
Nomad, Agricultural, and Industrial.
Basicallly, we're more advanced than the "cavemen" because we've learnt from other's mistakes. We are no more smarter, but have the advantage of accumulated knowledge from past generations relayed to us by our parents, media, books, and TEACHERS (Thank you Mrs. Andrews :)


HOMEWORK:
- LAB 32 IN UP- DUE MONDAY
- TEST TUESDAY
- FINISH UP FOR TUESDAY :)


next scribe: Claire T.

Wednesday, February 9, 2011

2/9/11

Today, we took a quiz.
Notes:

Human Ancestry

  • Early primates:

    evolved from insect-eating mammals during Cretaceous period (evidence from fossils)

  • were small

  • lived in trees (arboreal)

  • limber shoulder joints

  • could grab with their hands (dexterous)

  • nails started replacing claws

  • had depth perception (eyes close together in front of face)

  • eye-hand coordination

  • parents cared for their offspring



The 2 Major Primate Groups:

Prosimians

  • oldest

  • EX- lemurs, lorises, pottos, tarsiers
Anthropoids

  • EX-monkeys, apes, humans

  • New World monkeys

  • in the Americas

  • arboreal

  • prehensile tails-could swing by tails and grab things with them unlike dogs or cats, it functioned as an extra appendage

  • Old World monkeys

  • mostly ground dwellers

  • EX- baboons-

  • -Prehensile tail, New World

Human Ancestors

  • closest anthropoid relatives=apes
  • gibbons, orangutans, gorillas, chimps
  • apes today live in tropical regions of Old World
  • Humans
  • young twig on vertebrate branch
  • chimps and humans diverged from common ancestor 5-7 million yrs. ago

  • Our ancestors are not modern apes and chimps; we diverged on a different branch than they did, but we both evolved from a common ancestor
  • they are more like our cousins than anything else

  • Human evolution is not a series of steps leading directly from an anthropoid ancestor to Homo sapiens; other groups have traveled to dead ends and died off
  • Many different human species coexisted
  • We are a subspecies of Homo sapiens

  • Human characteristics did not evolve at the same time
  • They evolved at different rates
  • Bipedalism-walking on two feet, led the way
  • We had some ancestors who walked on two feet and upright, but they still had ape-sized brains

Kinds of Hominids

Australopithecus-walked African savanna, came before Homo genus:

  • A. afarensis
  • early species
  • bipedal
  • a skull was found that was about 3.9 million yrs. old. It had a vertical backbone which provided evidence that upright posture is at least that old
  • Lucy-very complete skeleton of A. afarensis, female, 3ft tall, 3.2 million yrs. old
  • footprints also found, bipedal footprints in Africa, 3.7 million yrs. old
  • bipedalism is a very old trait
  • Australopithecus went extinct about 1.4 million yrs. ago

Homework!!

Lab 32-due Monday

Up pgs. 69-70, read and questions

Next scribe:

Aliza!! :)

Tuesday, February 8, 2011

2/8/11 Class Overview


Notes:

How to tell geologic time using fossils

Macroevolution - large scale evolution (one species turns into another)
Microevolution - minor evolutionary changes

-Fossils in sedimentary rocks show that macroevolution has happened
-Earth's layers show a record of life
-Layers of sediment/fossil dating don't tell exact age... only ballpark/relative
-Layers closer to Earth's surface are youngest
-Deeper down low are older

4 Eras of Time: Precambrian, Paleozoic, Mesozoic, Cenezoic

Radiometric Dating

-Measure how much radiation a fossil releases as they break down
-The amount of radiation as well as level of decay give you exact years
-Half-Life=the amount of time it takes for half of a fossil to radioactively decay
--So if a bat fossil would normally take 100 years to decay, its half-life is 50 years
--Think of the decay period (100 years) as the fossil's life, half of it is 50
-To date very old fossils, paleontologists simply use isotopes with longer half-lives
-Isotope=an atom (like the M&M's in our lab today) with uneven numbers of protons/neutrons

Continental Drift: Pangaea

-The idea that all land in the world used to be one huge piece of land
-It broke apart slowly into the separate pieces of today
-Still breaking apart.... 2 cm/year (Thanks Nick)
-Impacts of land break=extinctions, species isolation according to continents
-Plate boundaries=place where 2 plates meet
-Earthquakes occur at plate boundaries





In-Class Lab: M&M's

Purpose: To learn how radiometric dating and radioactive decay work

-The M&M's represented atoms that were radioactively decaying
-We took 100 and kept decaying them randomly by spreading them out and removing the ones that had no "M" inscribed on top. The removal represented decay~
-Once they decayed to around 50, the half-life was found by seeing how much time it took to get to 50 because half-life is a time period

Quiz on all evolution tomorrow.

Next Scribe: Bridget