Neurons have sticking ______ out of them, that grow to network and share information developing an entirely new process of thinking.

A. carbohydrates

B. dendrites

C. axons

Present a Persuasive Speech

Student Resource

When you present a persuasive speech, keep in mind the elements of good public speaking, listed below. Remember, you will be presenting, not reading, your speech.

As you are touching up your speech to get it ready to present, you may want to add some visuals or multi-media as appropriate. Be aware that any media you use should clarify and enhance - not overpower - your speech.

 

In this activity, you will review Gram stains and apply your knowledge of this process to draw conclusions from images of Gram-stained bacteria. You will then answer some discussion questions about bacteria.

 

Gram Staining is a process of using different stains to identify bacteria based on the thickness of their cell walls. These stains stick to the peptidoglycan in the cell wall. After fixing bacteria to a slide there are four different stains used in this process. Crystal Violet is added to the slide and absorbed by the cell walls. lodine is then added and binds with the crystal violet in the cell wall, making it insoluble in water. Alcohol is used as a decolorizer so that any extra stain is removed. For bacteria with thin cell walls, this causes all the colored pigment from the crystal violet to run off. For bacteria with thick cell walls, the pigment becomes dehydrated and crystalizes in the cell. Since bacteria with thin cell walls now have no color, safranin is added to give the cell a pink color and make it visible. If the bacteria have a thick cell wall the Gram stain will turn out purple and if they have a thin cell wall it will be pink. After staining, bacterial cells can be classified as Gram-positive or Gram-negative.

 

Gram-positive bacteria have a thick cell wall and stain purple from the crystal violet. Streptococcus, staphylococcus, and S. epidermidis are examples of Gram-positive bacteria.

 

Gram-negative bacteria have a thin cell wall and stain pink from safranin. E. coli, pneumonia, and cholera are examples of Gram-negative bacteria.

 

In this activity you will classify and describe two different organisms from different phyla as well as describe the features that distinguish the phyla of your chosen organisms.

 

When classifying organisms each level or group gets smaller and more specific. Domain is the largest and most inclusive group. After domain is kingdom, phylum, class, order, family, genus, and then species. When naming organisms, the genus and species are used to create binomial nomenclature. This is a two-name naming system using the most specific and exclusive groups of the organism.

 

In the Domain Eukarya is the Kingdom Animalia. This kingdom contains nine phyla of animals: Mollusca, Porifera, Cnidaria, Platyhelminthes, Nematoda, Annelida, Arthropoda, Echinodermata, and Chordata. Each phylum has certain characteristics that are shared by all organisms in that group.

 

In this assignment you will choose one organism from two different phyla, so you will have two organisms total. The organisms you may choose from are listed below according to their phylum. For each of your chosen organisms you will classify them by listing their domain, kingdom, phylum, class, order, family, genus, and species, as well as their common name. Find or draw pictures of your organisms and list the features that distinguish their phylum in your submission.

 

Organisms: