Thursday, January 28, 2010

Just a few more questions for Botany

While there are many edible plants, humans consume only a few. What are the three most common plants in the diet, and where does each come from?

What characterizes a plant?

Between 1952 and 1992, twenty percent of all tropical and semi-tropical plants species became extinct. Why should this concern us?

What is photosynthesis?

What is a primary producer?

What elements should be part of a valid experimental design?

Botany Review Questions

Here are a host of review questions for you to prepare for the first exam
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. What are the major functions of carbohydrates in plant cells?
5. Which of the macromolecules we discussed stores energy in the most efficient way?
6. What are the building blocks or subunits of proteins?
7. What kind of fatty acids are usually made in plant cells?

Here's some more questions for you to answer !

1. How are polar and non polar covalent bonds different?
2. What is a hydrogen bond, and why are these bonds important to life?
3. Oxygen has 8 electrons, with 6 in the outermost energy leve. Will this atom react?
4. How are ions formed?
5. A solution with a pH of 5 is how many times more acidic than a solution with a pH of 7?
6. What determines if an atom with react with another?

Plant Cells, and how substances get into and out of cells
1. How are the mitochondria and chloroplasts similar?
2. Why do we think the mitochondria and chloroplasts were once independent organisms?
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. How is dialysis different from osmosis?
6. What affect would a 10% salt solution have on a plant cell?
7. Describe how a protein would get out of a plant cell.
8. What are the channels from one cell to another called?
9. How do plants use the central water vacuole?
10. are prokaryotic cells different from eukaryotics cells?
11.What can cyanobacteria do that the bacteria living in your mouth do not do?
12.What organelle is found on the ER?
13.Where is the nucleolus?
14What are the functions of the Golgi bodies?

Wednesday, January 20, 2010

A photosynthetic animal?

We have been discussing in class differences between plant and animal cells, and that one important difference between the two is that animals do not have chloroplasts. Well, that's true of most animals anyhow.

This beautiful green leafy organism is actually a sea slug. The sea slug Elysia chlorotica consumes chloroplasts when it eats the algae Vaucheria litorea. The slug feeds on the algae, but the chloroplasts are retained in the cells of the gut. The gut in this sea slug is highly branched and the chloroplasts give it the green color. The chloroplasts in the tissue of the animal's gut continue to function in the animals without an algal cell being present. The slug lives about 10 months and can survive off the food made by the chloroplasts.

The green color also provides great camouflage. While the animal has to eat an algae to get the chloroplasts, it is intriguing that the chloroplasts can continue to function without any algal cells present as genes in the nucleus of the algae are needed for photosynthesis to occur. So where are the genes to support photosynthesis? In the nucleus of the sea slug cells! The slug gets the genes from the algae, it does not have them until the animal feeds on the algae.

Interested in looking into this gene transfer further? Click here to read a paper by Mary E. Rumpho et al. on horizontal gene transfer between the algae and the slug.

Friday, January 15, 2010

Yellowstone Animals in Winter

Winter is a very hard time for the herbivores of Yellowstone. The grasses the grazing animals depend upon are dry, dormant and less nutritious than during the rest of the year. The other problem is that they may be buried under many inches, if not feet, of snow. So food is less available, and the weather is very cold,requiring the animals that stay active in the winter to turn their fat reserves into heat to stay warm.

This bison calf has a snowy nose because it has been pushing snow out of the way to find food. Bison do migrate to lower elevations in the winter, and also leave the park. This causes problems for them as they are hunted, and rounded up and often sent to slaughter since local ranchers are concerned they may transmit a disease called brucellosis to cattle. The irony of the situation is that the cattle gave the disease to the bison in the first place.

Bison, however, are well adapted for the cold Yellowstone winters. During the winter their coat of coarse hair can be as much as two inches thick. This provides excellent insulation against the cold.

The snow does not accumulate in such deep layers around the hot springs and other thermal features so the bison there do not have to move as much snow around as the ones who winter well away from the hot springs. There are dangers, however, of life around the hot springs. Bison are huge, heavy animals. They can weigh 2,000 pounds and sometimes as they walk around the thermal features they break through the thin crust of soil and fall into the hot springs and die.

I photographed this bighorn sheep ram in one of the lower elevation areas of the park. Migration to lower elevations where there is less snow is a solution to the problem of winter adopted by many of the herbivores in the park.

I was very surprised to see this squirrel active early in January. Most of the squirrels hibernate during the winter, but this one was not at all sleepy it seems. It scampered across the trail in front of me, ran up into this tree, paused for a few seconds and then was on to another tree.

These cow elk form large herds with their calves and younger elk. Here they are watching the landscape from a high point to better detect their main predator, wolves.

As winter takes its toll on elk, bison, deer and other animals in Yellowstone animals such as this coyote will benefit from feeding on the carcasses of winter killed animals. They also feed on mice and voles, animals that stay active under an insulating blanket of snow.

I was surprised by the number of birds I saw during my winter trip. Many of the ducks, and this beautiful trumpeter swan, forage in the Firehole River. Water flowing from geysers, and hot springs into the river keeps it flowing year round which provides habitat for a host of birds.

Wednesday, January 6, 2010

Winter in Yellowstone

I just got back from Yellowstone National Park. I took a class on wolves in winter though the Yellowstone Association and spent 3 days looking for and watching wolves. We saw at least 4 or 5 different packs of wolves. Most of the time we needed binoculars or spotting scopes to observe the wolves, but we did see one wolf that was on a hillside about 100 or so yards away. The wolf howled for 15 minutes or so before moving out of sight.

Elk are the primary prey of the wolves, and we saw large herds of cows and calves. The bull elk separate themselves from the cows and form bachelor herds. If it looks cold in this photo, it was. It was below zero when I took the photo.

Coyotes are killed by wolves, but they are often found not far from wolves while hunting for rodents. Mice and voles remain active through the winter under the snow. The snow forms an insulating blanket, and protects them from the wind. It also makes it hard for the coyotes to find them except by sound.

In the winter the hot springs create a lot of mist. The mist then condenses on the trees, coating them in an icy blanket.

The water from the thermal features in the park carve channels in the snow, creating beautiful patterns as the hot water flows away from the springs and geysers.