Saturday, February 27, 2010

Bio 120 review for the second exam

Genetic Engineering

1. What are restriction enzymes?
2. What kind of cells have restriction enzymes, and what is the purpose of these enzymes in the cell?
3. What is a plasmid?
4. How are plasmids used in genetic engineering?
5. Why does human DNA work in a bacterial cell?
6. What is gene therapy?

Mitosis and Meiosis Review

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

2. 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?

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

4. What are homologous chromosomes?

5. What are sister chromatids?

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

7. Why is crossing over important?

8. During __________ of mitosis sister chromatids separate.

9. During _________ of meiosis homologous pairs of chromosomes separate, but during ____________ of meiosis sister chromatids separate.

10. In meiosis, typically four sperm cells are made, but meiosis only makes one large egg cell. Why?


DNA Review Questions

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, February 25, 2010

Botany Review for the Second Exam

DNA
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 complementary 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. 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?


Mitosis and Meiosis

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

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

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

4. What are homologous chromosomes?

5. What are sister chromatids?

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

Plant Anatomy:

1. Pick one of the ground tissues we discussed such as parenchyma or sclerenchyma, and explain how its structure and function are related.

2. What are the two types of vascular tissue in plants, and what is the function of each?

3. How is the anatomy of a monocot root, or stem or leaf different from that of a dicot?

4. What is the role of the epidermis? In woody plants the epidermis is replaced by the _______ ?

5.What are the regions called in plants where mitosis occurs to make the plant taller?

6. What is the name of the openings in the epidermis and what is the function of these openings?

7. In a dicot leaf, why is the lower layer of mesophyll more open than the upper layer?

8. What part of the root actually absorbs the water?

9. What is the difference between spring and summer wood?

10. How are compound and simple leaves different?

11. What is the function of the following stem modifications: tuber, bulb, corm, rhizome, stolon, tendril

12. What are five modifications of stems or leaves that might be found in a plant adapted to hot dry conditions?

13. Why are some plant's leaves modified to trap insects?

14. What is the role of the endodermis in the root?

15. What is the function of the pericycle?

Saturday, February 20, 2010

Bolsa Chica Stewards Volunteers Plant over 300 plants on the Bolsa Chica Mesa

The Tree of Life Nursery could not deliver the plants out onto the mesa for us since the ground was so wet from all the rains, so we carried the plants out by hand or in wagons and wheelbarrows. The Bolsa Chica Stewards had wonderful weather this morning as we planted, and pulled weeds away from plants put in during the last couple of months. There was a big turn out from Cerritos College students. This was the first month we were able to use the walk-bridge instead of walking on Warner Ave. This made a huge difference in safety for our volunteers.








Friday, February 19, 2010

Tinkering with Ribosomes and Protein Production

National Public Radio had a story this week about making new kinds of proteins by altering the way the ribosomes read the DNA code. As you know, ribosomes understand mRNA in groups of three bases called codons. Listen to this short report about scientists who have discovered how to get ribosomes to recognize codons made of four bases.

Saturday, February 6, 2010

El Nino and Southern California

The unusual amount of stormy weather we've been having is being caused by a condition called El Nino. El Nino is caused by a change in ocean currents. Warm ocean water is moving further north than usual. This has impacts on weather, and impacts on plants and animals.

NOAA, The National Oceanic and Atmospheric Administration defines El Nino this way, "El NiƱo is a disruption of the ocean-atmosphere system in the Tropical Pacific having important consequences for weather and climate around the globe."

NOAA predicts this El Nino will extend into the Spring in the US. That means we may see more storms which is great for native plants and we will probably have a good wildflower season in our deserts.
Primrose, Baja California

However, if El Nino persists, and warmer ocean temperatures stay with us through the spring and summer, there could be serious consequences for endangered wildlife.
The brown pelican was just removed from the endangered species list. The population has recovered, but pelicans in Washington State and Oregon are starving right now because the storms keep them from feeding, and their food is moving deeper into the oceans to escape the warmer water temperatures.

The California least tern is an endangered species that nests at Bolsa Chica, and beaches in Southern California. It feeds small fish such as anchovies to its chicks. In El Nino years fewer eggs are laid because the tern's food moves deeper, or north to cooler waters.

El Nino also affects the wildlife off the coast of Ecuador along the Galapagos Islands. During the 97-98 El Nino large numbers of Galapagos penguins died as did the marine iguanas. The marine iguanas eat algae and when the water warms, the algae dies.

Marine iguanas feed on algae, and during times of food shortages can actually re-absorb their own bones to stay alive.

Thursday, February 4, 2010

Summer Bio 120 review for first exam

Here are some review questions for you. Some may be similar to the daily review questions, but all will help you while you prepare for the exam.

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 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?
11. How are the mitochondria and chloroplasts similar?
12. Why do we think the mitochondria was once an independent organism?
13. Describe the plasma membrane. Include how a lipid membrane functions in a watery environment.
14. What role do the proteins in the plasma membrane play?
15. How is active transport different from diffusion and osmosis, and faciliated diffusion?
16. How is dialysis different from osmosis?
17. What affect would a hypertonic solution have on a cell?
18.How is a hypothesis different from a theory?
19.What are five characteristics of living things?
20.How are prokaryotic cells different from eukaryotics cells?
21.What can cyanobacteria do that the bacteria living in your mouth do not do?
22.How are archeae different from the bacteria living on your skin?
23.Describe briefly what organelles would be involved in making a protein and exporting it from the cell.
24.Give an example of two cell organelles working together to accomplish a task.
25.What organelle is found on the ER?
26.What is the function of lysosomes?
27.Where is the nucleolus, and what is its function?
28.What are the functions of the Golgi bodies?

Chapter 3
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. Which of the macromolecules we discussed stores energy in the most efficient way?
9. What is the most common steroid in the body?