1-Explain six of the following terms with reference to the Mollusca. In your answer be as comprehensive as possible regarding each term and use illustrations. a) mantle cavity, b) radula c) ctenidia, d) Monoplacophora, e) trochophore, f) pulmonate gastropod, and g) torsion.

2-Describe how the gnathostomes developed a jaw, and discuss how this adaption has benefitted later chordate species.

1) Describe the use of Small SubUnit ribosomal RNA (SSU rRNA) gene sequences for the identification of bacteria in microbial communities. 100 marks

2) Describe how the genetic content of a bacterium determines the bacterium’s activities and behaviours. 100 marks

1- What is the purpose of the IMViC series of tests? Explain the underlying biochemistry of each reaction and describe how each test is carried out. 100 marks

2-“The human microbiome is our newest organ.” Discuss this statement with references to the normal flora inhabiting different body sites and its associated benefits.100 marks

1. What is lactose?  
2. What codes for the production of the repressor?  
3. Why would the bacteria want to regulate the production of certain genes?  
4. When would the repressor be bound to the lac operon?  
5. What would happen if the repressor binds to the operator in the lac operon?  
6. What happens when there is lactose in the environment?  

Question: You perform a lab where you are instructed to observe the characteristics of a lipid molecule in oil and water and are told to conduct 3 trials each time for the lab. You noticed that you get the same observations for all 3 trials for the lab. Explain in detail why you were asked to complete 3 trials? Why were you not asked to complete 1 trial?

21. What is the ecological significance of the glomeromycetes (Glomeromycota)?

22. What are arbuscules?

23. Mycorrhizae are symbiotic relationships between fungi and ___________________________ ______________________________________.

24. What does each partner get from their mycorrhizal association (how does each partner benefit)? Explain.

25. The ascomycetes (Ascomycota) are commonly called the sac fungi. They produce reproductive structures called ________________________ that contain sexual spores called ___________________________________. The reproductive structures and their spores are housed within the cup-like structure known as an___________________________________.

26. List some examples of pathogenic (disease-causing) ascomycetes:

27. List some examples of useful ascomycetes:

28. After going through meiosis to produce four haploid nuclei, the ascomycete nuclei divide by _______________________________ to produce eight haploid ascospores.

29. The familiar fungi known as mushrooms belong to the group of fungi known as _____________________________________ (phylum = _____________________________).

30. The structures that produce spores within mushrooms are called _____________________. The mushroom structure itself is called a ______________________________.

31. List some beneficial aspects of the basidiomycetes:

32. List some harmful basidiomycetes:

33. What are “gills” in the mushroom group?

34. What is a lichen? Explain, in some detail.

35. How does each partner benefit in a lichen? Explain.

36. What is the ecological significance of lichens?

37. There are some plants that require mycorrhizal associations. List some types of plants or plant environments that require mycorrhizal associations for the healthy growth of the plant. Know some common examples of fungi and which group they belong to. For example, mushrooms; yeast (including those in bread/beer and in yeast infections); bread mold; Penecilium; puffballs, chytrids; truffles; ring worm/athlete’s foot; Aspergillus.

38. How are blue stain fungus, pine trees, and bark beetles connected? Explain.

39. How are fungi, bats, and white nose syndrome connected? Explain.

40. What are entomopathic fungi? Explain.

explain how the following factors influence the rate and depth of respiration:

increased body temperature,

exercise,

talking and

coughing

1. Explain why DNA is the ideal genetic material. That is, explain how DNA uniquely fulfills these properties of the genetic material:

   1. Stores information securely

   2. Is replicated accurately

   3. Genetic information can be used

   4. Genetic variability occurs so that species can evolve

BioChemistry Problem

State whether the Hill Coefficient (N) is positive or negative? Explain your reasoning in each case.

(a) The protein has multiple subunits, each with a single ligand-binding site. Binding of ligand to one site increases the binding affinity of other sites for the ligand.

(b) The protein is a single polypeptide with two ligand-binding sites, site one causes a structural change that decreases affinity for the second ligand.

(c) A molecule binds to a protein and inhibits binding of the natural ligand.

(d) The protein has two subunits and as one ligand binds, the second binds with lower affinity.

1.  What is unique about fish? How is it best to care for them? What does the aquarium industry look like?

2. Think about all the fish species we have in captivity. Are fish domesticated? If so, all?

3. What is the difference between tropical and marine aquaria?

4. How are fish for the aquarium industry produced?

5. Why is overfeeding fish a concern?

1. Discuss 4 - 5 features how prokaryotes in general are different from eukaryotic members. Include how prokaryotes as well as eukaryotes belong to the microbial world.

1. Which experimental treatment/s would have E. coli cells that are genetically identical to original cells used to set up the experiment? Explain why they are likely to be genetically identical.
2. For bacteria transformation to occur cells must allow foreign DNA to pass across the cell membrane.
   1. What is one advantage to allowing transformation?
   2. What is one disadvantage to allowing transformation?

Material:

• Plant tissue (strawberries or split peas)
• 400-mL beaker
• Blender
• Table salt
• Tablespoon
• 1/8 teaspoon
• Liquid detergent
• Test tubes and test tube rack
• Meat tenderizer
• Glass rods
• Ice-cold 70–95% ethanol
• Ice-cold dH₂O
• Strainer

Procedure – DNA Extraction

1. Combine in a blender:

• 1/2 cup frozen green split peas or approx. 1/2 cup frozen strawberries
• 1/8 teaspoon table salt
• 1 cup cold (refrigerated or use ice to chill) water

2. Cover and blend on the high setting for 30 seconds.
3. Pour the blended material through a strainer into a 400-mL beaker. Discard the solid material trapped by the strainer into the trash. This step removes the seed coat and the cell walls from the plant cells.
4. Add 2 tablespoons of liquid detergent to your beaker and swirl to mix. Let the mixture stand for approximately 10minutes. Detergents dissolve lipids, such as phospholipids in plasma and nuclear membranes.
5. Obtain a test tube for each member of each of your group.pour the mixture into the test tubes until they are each about 1/3 full.
6. Add a pinch of meat tenderizer to each test tube and stir gently with a glass rod. if you stir. vigorously, you will break the DNA into short strands that are had to see. Meat tenderizer contains enzymes that digest histones, the proteins around which the DNA is wound.
7. Tilt your test tube and slowly pour cold 70-95% ethanol down the side of the tube so it forms a layer on top of the DNA mixture until you have the same volume of alcohol as the DNA mixture.
8. After a few minutes, the DNA will rise into the alcohol layer. DNA forms a whitish layer at the interface between the alcohol and the lower cell debris-containing layer.

1:Why did you add detergent to the homogenized tissue sample?

2:How did you remove the cell walls.

3:Why did you add meat tenderizer to your test tubes?.

4:What are histones