Category: 2nd Semester

Annelid

Annelids
Segmented Worms
All Materials © Cmassengale 

Phylum Annelida
Characteristics

  • Includes duster worms, earthworms, & leeches
  • Abundant in all habitats
  • Have a true coelom fully lined with mesoderm
  • Body divided into external segments called metameres (metamerism)

  • Metameres correspond to internal segments
  • Have a one-way digestive system with a mouth & anus
  • Well developed brain & sensory organs
  • Fluid-filled coelom provides hydrostatic skeleton
  • Most have external bristles or setae that aid movement
  • Setae may be modified into flashy appendages called parapodia


PARAPODIA

  • Includes 3 classes based on number of setae & presence or absence of parapodia
  • Classes of segmented worms — Oligochaeta, Polychaeta, & Hirudenia

Class Oligochaeta
Characteristics

  • Have no parapodia & few setae
  • Includes earthworms


EARTHWORM

  •  Bodies may have over 100 metameres
  • Internal partitions called septa
  • Distinct anterior & posterior ends
  • Cephalization (head with sense organs) shows specialization for burrowing
  • Have both circular & longitudinal muscles for movement
  • Have external, saddle-shaped structure called clitellum that forms a cocoon containing eggs & sperm
  • Prostomium or lip digs through soil as earthworm feeds on organic matter
  • Pharynx is a muscular organ behind the mouth to help suck in food
  • Food temporarily stored in crop, ground in gizzard, and digested & absorbed in intestine
  • Wastes called castings pass out through anus
  • Closed circulatory system with 5 pairs of aortic arches or hearts
  • Dorsal blood vessel carries blood posteriorly to cells & ventral blood vessel returns blood anteriorly

  • Secrete mucus to keep skin moist so oxygen will dissolve & diffuse into body
  • Long tubules called nephridia filter wastes from blood & excrete it through pores
  • Simple brain, no eyes, & dorsal and ventral nerve cords
  • Sensitive to light, touch, moisture, chemicals, temperature, & vibrations
  • Hermaphrodites exchange sperm & cross-fertilize
  • Sperm sacs store the worm’s own sperm & seminal receptacles store exchanged sperm

Class Hirudenia
Characteristics

  • No setae or parapodia
  • Includes leeches
  • Have anterior & posterior suckers for attachment


LEECH

  • Some suck blood from hosts, while others are scavengers or predators
  • Mouth’s of blood-sucking leeches with chitinous teeth & secrete anticoagulant
  • Found in freshwater
  • Flattened dorso-ventrally
  • Hermaphrodites that cross-fertilize

Class Polychaeta
Characteristics

  • Marine
  • Includes sandworms & clamworms
  • Have paddle-like parapodia to move
  • Take in oxygen through parapodia
  • Some are free-swimming predators with strong jaws to feed on small animals
  • Many live commensally with sponges, mollusks, & echinoderms
  • Well-developed head with antenna & specialized mouthparts


SANDWORM

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Virus Worksheet

 

  Viruses Worksheet   

Structure of Viruses

1. Are viruses living or nonliving?

2. How can viruses be useful?

 

3. What odes a virologist do for a living?

 

4. Construct a Venn diagram comparing viruses and cells.

 

 

 

 

 

 

 

5. Explain how viruses were discovered and by whom.

 

 

6. Compare the size of viruses, bacteria, and eukaryotic cells.

 

 

7. What must be true for viruses to be able to replicate?

 

8. Name the two main parts of all viruses.

 

9. Discuss the hereditary material of viruses.

 

 

10. Compare & contrast capsids and envelopes of viruses.

 

 

11. Name 2 enveloped viruses that cause sexually transmitted disease.

12. What type of virus causes flu?

13. Where are glycoproteins found & what is there purpose?

 

14. What characteristics are used to group viruses?

 

15. How are these viruses grouped — retrovirus, adenovirus, and herpes virus?

 

 

16. Compare & contrast helical & icosahedral viral shapes & diseases.

 

 

17. Explain how RNA viruses replicate.

 

 

18. Do viruses contain enzymes? Explain.

 

19. Compare 7 contrast viroids & prions by constructing a Venn diagram.

 

 

 

 

 

 

Viral Replication

20. Why are viruses considered to be obligate intracellular parasites?

 

21. What is the best known bacteriophage, and what virus does it attack?

 

22. Sketch & label a bacteriophage and tell the function of each labeled part.

 

 

 

 

 

23. Name the steps of the lytic cycle & tell what happens to the host cell & virus at each stage.

 

 

 

 

 

24. What are temperate phages and how do they affect a cell?

 

 

25. Name the steps of the lysogenic cycle & tell what happens to the host cell & virus at each stage.

 

 

 

 

26. How does a prophage form?

 

27.Name a sexually transmitted virus that uses the lysogenic cycle to attack host cells.

28. Why is the influenza virus so hard to combat?

 

Viruses & Human Disease

29. Name some of the most common viral disease that attack humans.

 

30. How are shingles & chickenpox alike? How are they different?

 

31.What two methods are used to control viral diseases?

 

32. What is the CDC and what is its job?

 

33.What eradication program did the World Health Organization undertake in 1967, and what were the results?

 

34. What virus do we vaccinate our pets against each year?

35. How does AZT work?

 

36. What drugs prevent viruses from making capsids?

37. Why is rain forest clearing dangerous to humans?

 

38. Some lysogenic viruses can trigger certain types of _________________.

 


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Antibiotic Resistant Lab

Antibiotic resistance of bacteria

Procedure Using a sterile loop, pick an isolated colony from you bacterial plate. Try to find one that grew well but is all by itself. Move the colony (don’t scoop up the agar) to a new plate. Using a moist, sterile, cotton swab, spread the bacteria around on the plate.

The goal is to get an complete, even, coverage of bacterial growth on the plate (called a “lawn”). Remember to open the plate only minimally, using the lid as an “umbrella” to prevent contamination (see image below). Label each plate on the bottom (agar contaning side) and store it for examination during next week’s lab.Each new prepared plate will receive four paper discs containing antibiotics. We will be using several different types of Antibiotics and/or antimicrobials.

(please fill in which antibiotics you used below)

  • 1
  • 2
  • 3
  • 4

The antibiotic discs come in a little tube-like dispenser. To remove the discs take a sterile toothpick and push out a disc into your plate. Use the toothpick to gently press the disc onto the agar. Once you have added the five antibiotic discs to your plates, make sure the plates are labelled and store them in the back of the lab until next week.

If the bacteria are susceptible to the antibiotic a zone of inhibited growth will be evident next week. Measuring the size of this zone is a relative indication of the effect of the antibiotic on the particular bacteria.

Bacteria possess several characteristics that enable them to become resistant to antimicrobial drugs:

  • Asexual reproduction
  • Short generation times
  • High mutation rates

Some Information on Antibiotics

Questions –

1. Name two ways (1. and 2. ) that common human practices towards antimicrobials aids bacteria in becoming resistant.

 

2. Name two reasons your Physician will perform cultures such as the ones you have done in this lab.

 

 

4. How are materials are collected for cultures?

 

 

5. Why is neccesary to use sterile technique when obtaining cultures?

 

Alien Invasion

 

Alien Invasion

Help! Aliens have landed on Earth from another planet. Before scientists can release the aliens, they want to identify and classify them. Use the dichotomous key on the next page to identify these creatures.

 

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   A Key to Alien Creatures:

 

1. a. The creature has a large wide head…………………………………….go to 2
b. The creature has a small narrow head……………………………….go to 11
2. a. It has 3 eyes ……………………………………………………………………………..go to 3
b. It has 2 eyes …………………………………………………………………………….go to 7
3. a. There is a star in the middle of its chest………………………….go to 4
b. There is no star in the middle of its chest ………………………go to 6
4. a. The creature has hair spikes ………………………………………..Broadus hairus
b. The creature has no hair spikes…………………………………………..go to 5
5. a. The bottom of the creature is arch-shaped ……………Broadus archus
b. The bottom of the creature is M-shaped ……………….Broadus emmus
6. a. The creature has an arch-shaped bottom ……………….Broadus plainus
b. The creature has an M-shaped bottom……………………Broadus tritops
7. a. The creature has hairy spikes ……………………………………………go to 8
b. The creature has no spikes…………………………………………………go to 10
8. a. There is a star in the middle of its body ………………..Broadus hairystarus
b. The is no star in the middle of its body ………………………..go to 9
9. a. The creature has an arch shaped bottom ……………….Broadus hairyemmus
b. The creature has an M shaped bottom ……………………Broadus kiferus
10. a. The body is symmetrical ………………………………………………Broadus walter
b. The body is not symmetrical……………………………………….Broadus anderson
11. a. The creature has no antennae ……………………………………….go to 12
b. The creature has antennae …………………………………………….go to 14
12. a. There are spikes on the face ………………………………….Narrowus wolfus
b. There are no spikes on the face ………………………………….go to 13
13. a. The creature has no spike anywhere ……………………Narrowus blankus
b. There are spikes on the right leg ………………………..Narrowus starboardus
14. a. The creature has 2 eyes…………………………………………………go to 15
b. The creature has 1 eye……………………………………………Narrowus cyclops
15. a. The creature has a mouth……………………………………………..go to 16
b. The creature has no mouth…………………………………………..go to 17
16. a. There are spikes on the left leg ………………………..Narrowus portus
b. There are no spikes at all ………………………………….Narrowus plainus
17. a. The creature has spikes ………………………………………………go to 18
b. The creature has no spikes ……………………………..Narrowus georginia
18. a. There are spikes on the head …………………………………..go to 19
b. There are spikes on the right leg……………………..Narrowus montanian
19. a. There are spikes covering the face ……………….Narrowus beardus
b. There are spikes only on the outside edge of head ……Narrowus fuzzus

 


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