Thursday, May 31, 2007

Evolution Quesitons

1. How do biologists define evolution?

2. What is a population?

3. What islands were important to Charles Darwin's thinking on evolution?

4. Biogeography is how living things are distributed around the world. How was Darwin surprised by the the biogeography he observed on his trip around the world?

5. While fossils support the theory of evolution, we can't rely on the fossil record ever being complete. Why?

6. How does the existence of fossils support the theory of evolution?

7. How did LaMarck explain inheritance?

8. What was the hypothesis of catastrophism?

9. While the theory of evolution does not indicate humans came from chimps, it does indicate a _________________________ between chimps and humans.

10. Upon what observations did Darwin base his theory of evolution by natural selection?

Tuesday, May 29, 2007

Snowy Plovers at Bolsa Chica



Hello again,
This afternoon I went out to Bolsa Chica to photograph some birds. At Bolsa Chica there is protected nesting habitat for an endangered bird called the snowy plover. They are small shorebirds that pick insects and bits of food off of the sand. Traditionally they nested in Southern California on sandy beaches. You can probably guess why they are now endangered. Over Memorial Day weekend I saw two chicks gleaning food alongside their dad by the water's edge. I was worried today since I saw two adults by the water, but no chicks. In addition I saw 6 gulls feeding on the carcass of an octopus right near where I had seen the chicks and adult plovers feeding. A snowy plover chick would make a nice snack for a gull. However as I walked on a bit I saw dad running around and herding two chicks away from the water. How do I know the adult is dad and not mom? Snowy plovers are polyandrous. This means many males. Mom mates with dad, lays the eggs and incubates them. When they hatch mom leaves to find another mate, and dad raises the chicks.

Notice the camouflage of the chick? These chicks are very precocious. They leave the nest shortly after hatching and can feed themselves.

Bio 120 Questions DNA

Here are some review questions about DNA from the lecture today.

1. Describe the structure of the DNA molecule

2. If the sequence of bases on one stand of the molecule is AAC TGC CCG, what is the sequence on the complemetary strand?
3. During DNA replication, what enzyme breaks the hydrogen bonds between the base pairs, and what enzyme matches up nucleotides to the existing ones on the parent strand of DNA?

4. Why is this type of replication called Semi Conservative?

5. How is RNA different from DNA?

6. The production of messenger RNA from DNA is called ________, and this happens in the __________ of the cell.

7. The parts of the mRNA molecules which are edited out before RNA reaches the cytoplasm are called __________

8. mRNA gets a cap and a tail prior to being read by the ribosome. What is the function of the cap and tail?

9. If the DNA strand being copied had this sequence: ACT GGC ATA CTA what would the sequence of the mRNA be?

10. The function of transfer RNA is ?

11. What is the name of the enzyme that produces RNA from DNA?

12. If the sequence of DNA is the same in your body cells, why are all cells not the same?

13. The DNA in you, an earthworm, and a fungus is the same. So why are you a human and not an earthworm?

14. What is an anti-codon and where is it found?

15. The protein synthesis process that occurs at the ribosome is called _____________

16. What is a stop codon?

Thursday, May 24, 2007

Macromolecule questions

1. What are the building blocks of carbohydrates?
2. What is the difference between a saturated and unsaturated fatty acid?
3. Why is the shape of an enzyme important to the function of the enzyme?
4. At what level of complexity do proteins usually become functional?
5. What makes up a nucleotide?
6. What bond forms between amino acids as they react to form proteins?
7. How is the function of carbohydrates different in plants and animals?
8. What is the name of the carbohydrate human cells use to store glucose?
9. Which of the macromolecules we discussed stores energy in the most efficient way?
10. What is the most common steroid in the body?

Wednesday, May 23, 2007

More Bolsa Chica Birds




It was very windy out at Bolsa Chica today, which some of the terns used to their advantage. The snowy egrets were also out hunting fish, but they use a different method. The black skimmers were fishing as well.

More Bio 120 Questions

Here's some more questions for you to answer !

1. A cell must maintain an imbalance of sodium ions on either side of the membrane for it to function. What process would it most likely use of the ones we discussed today in class?

2. How are polar and non polar covalent bonds different?

3. What is a hydrogen bond, and why are these bonds important to life?

4. Oxygen has 8 electrons, with 6 in the outermost energy leve. Will this atom react?

5. How are ions formed?

6. A solution with a pH of 5 is how many times more acidic than a solution with a pH of 7?

7. What determines if an atom with react with another?

8. A plant cell in a hypertonic solution will under go _____________

9. An animal cell in a hypotonic solution may undergo _____________

10. A Paramecium can survive in fresh water without bursting. Why?

Tuesday, May 22, 2007

Birds at Bolsa Chica



Both of these photographs are of the same species of bird. They are eared grebes. In the winter they are black and white, but they are now in breeding plumage and should be migrating soon to nesting areas in the Northern US and Canada. It gets its name from the beautiful golden feathers on its head.

Bio 120 Questions

Good Afternoon Budding Biologists ! Here are more questions for you from today's lecture!
If each person in class tried to answer just one or two of these, they would all be answered for everyone!

1. How are the mitochondria and chloroplasts similar?

2. Why do we think the mitochondria was once an independent organism?

3. Describe the plasma membrane. Include how a lipid membrane functions in a watery environment.

4. What role do the proteins in the plasma membrane play?

5. If a cell has 8 chromosomes and does mitosis, how many cells will be made, and how many chromosomes will each cell have?

6. If a cell has 8 chromosomes and does meiosis to make sperm cells, how many cells will be made, and how many chromosomes will each cell have?

7. Mitosis creates cells which are ________, while meiosis makes cells which are _____.

8. What are homologous chromosomes?

9. What are sister chromatids?

10. What is crossing over, and during which process, (mitosis or meiosis) does it occur?

Monday, May 21, 2007

Bio 120 Questions

Here's some questions for review based on today's lecture

How is a hypothesis different from a theory?

What are five characteristics of living things?

How are prokaryotic cells different from eukaryotics cells?

What can cyanobacteria do that the bacteria living in your mouth do not do?

How are archebacteria different from the bacteria living on your skin?

Describe briefly what organelles would be involved in making a protein and exporting it from the cell.

Give an example of two cell organelles working together to accomplish a task.

What organelle is found on the ER?

What is the function of lysosomes?

Where is the nucleolus?

What are the functions of the Golgi bodies?

Wednesday, May 16, 2007

Bolsa Chica Birds, and others




The black skimmers are back! Mr. Covill told me earlier in the week he saw skimmers at Bolsa Chica, and I was able to photograph one today as it flew past. Skimmers are the only bird that has a lower jaw longer than its upper jaw. When they feed they fly low along the surface of the water with their lower jaw skimming along in the water. When it touches something (a fish one hopes) the bird snaps its jaw shut on the food. Because skimmers feed by touch, they often hunt at night.

My friend Jim, found this other animal. He heard it then he saw it. I was really glad I had my camera today, as the last time I saw pacific rattlesnake at Bolsa Chica I didn't have my camera with me. This is the most common snake at Bolsa Chica. My other friend Carrie saw the beautiful cactus in bloom, and I though you might enjoy seeing these wonderful blooms.

Tuesday, May 15, 2007

Bio Questions and discussion

Hello Bio 120 students,
Please use this blog as a place to ask questions about the class or discuss questions you may have about the material we are covering in class. I encourage members of the class to answer questions posted by other students. This is a moderated blog in that the posts are emailed to me first, then posted so keep the discussion civil and free of offensive language or your posts will not reach the blog.

Monday, May 14, 2007

Birds at Bolsa Chica



The terns have returned in force to the Bolsa Chica Ecological Reserve! A couple of Foresters terns have discovered its easier to fish from a standing position on the handrails of the walkbridge over the wetlands than it is to hover and dive into the water. I haven't noticed any black skimmers yet, but the least terns and snowy plovers can be seen on the sandy nesting area behind the fence at the end of the walkbridge.

The great blue herons are nesting in the eucalyptus trees on the Bolsa Chica Mesa. There are at least 6 nests, probably more in the trees.