True or false?

True False  In cell membranes, cholesterol decreases membrane fluidity below the transition temperature, but increases membrane fluidity above the transition temperature.
True False  Escherichia coli cells grown at 40°C would be expected to have a lower percentage of unsaturated fatty acids in their membranes than cells grown at 20°C.
True False  If a sphingolipid contains sialic acid (a.k.a. neuraminic acid) in its oligosaccharide headgroup, the headgroup will have a new negative charge of minus one.
True False  Groups lining the pores of transport proteins form weak non-covalent interactions with solute molecules that replace the water molecules that normally hydrate the solute.
True False  In active transport, the transported species moves across the membrane against a concentration gradient.
True False  Myristoyl, palmitoyl, and farnesyl groups anchor otherwise soluble proteins to the extracytoplasmic face of the plasma membrane.
True False  Triacylglycerols have three ester-linked phosphoryl groups that can in turn be ester-linked to serine, choline, ethanolamine, or inositol.
True False  In an amphipathic alpha helix, non-polar amino acid side chains face one side of the helix, and polar uncharged side chains face the other side.

Using DNase footprinting, show that the sigma subunit of prokaryotic RNA Pol binds to nucleotides from -35 to -10 in the promoter region.

a. Outline your experiment and draw and label the data. Explain how your data support this conclusion.   

b. Show and label the data for a similar experiment done using DMS footprinting rather than DNase foot printing. Explain how your data support this conclusion.  You do NOT have to write out the experiment again.

Let's begin with an overview of urine formation. What exactly is urine? How can it be used as a diagnostic tool? What does urine from a healthy person contain? How can urine contents be used as an indicator of health or disease?

Trace your way from the electron transport chain to the citric acid cycle. In a few sentences, explain why the citric acid cycle stops when the electron transport chain is completely inhibited.

1)Cell walls are rigid and resist expansion, which allows the pressure to build inside a cell when it absorbs water. The force exerted by pressing water against the cell wall is called [BLANK1], which is a key feature that allows plants to stand upright.

2)Prokaryotes concentrate DNA in a discrete region of the cell interior known as the BLANK . They often contain additional small circular molecules of DNA known as BLANK that carry a small number of genes that are commonly transferred between bacteria through thread-like hollow structures known as BLANK . Genes for antibiotic resistance are transferred, which accounts for the quick spread of antibiotic resistance among bacterial populations.

3)The [1BLANK] is a rigid structure that surrounds the plasma membrane of some organisms to help maintain the cell shape and volume and also functions in support and protection.

4)

The shape of the phospholipid structure is determined by the bulkiness of the head group relative to that of the hydrophobic tail. Lipids with bulky heads and a single hydrophobic fatty acid tail forms  spherical structures called what?

5)The BLANK and BLANK are both semi-autonomous organelles that grow and multiply independently and contain their own genomes.

6)Protein sorting is a process by which proteins end up where they need to be to perform their function.  Proteins produced by free ribosomes are often directed to their proper cellular compartments by means of particular amino acids called signal sequences.

Match the type of signal sequence used in the making of proteins that direct them to the correct cellular destination.

1)Why would you predict that an animal cell, but not a plant cell, might burst when placed in a hypotonic solution?

2)If a bowl of fresh strawberries is sprinkled with sugar, a few minutes later the berries will be covered with juice. Why?

A. Sugar is causing water to move out of the cells. The water mixing with the sugar will form the juice

B. Strawberries contain enzymes to break down the sugar to release the water in the sugar, which mixes with the water on the outside of the strawberries to form the juice

C. Sugar is moving inside the strawberry cells and mixing with the water inside and the juices are leaking out as the cells cannot hold the fluid

D. Sugar is causing the all the strawberry cells to breakdown and release the juice

3)Grocery store owners will frequently spray fresh fruits and vegetables with water to prevent them from wilting or drying out. This loss of water is called what in plants?

A. Turgor pressure

B. Isotonic tonicity

C. Plasmolysis

D. Hypotonic tonicity

4)Strong cell walls and water-filled vacuoles help maintain [1] to help plants to stand upright.

5)For the egg experiment, explain how the tonicity changed when the unshelled egg went into a corn syrup solution and when the egg went into the colored water solution. Describe what was happening in relation to osmosis.

The Sacramento area was founded on the prospect of gold. Gold discovery in nearby Coloma brought countless people west with hopes of richer days and better choices for their families. In collaboration with a local merchant Sam Brannan, John Sutter and his family founded the city of Sacramento in 1848. In April of 1849, the population of the area was estimated at 150 people. By October of the same year, the population grew to a whopping 6,000 people (Wiegand, 1998). In mid-October of 1850 it is reported that a riverboat named the “New World” arrived in the area with a single passenger carrying the deadly cholera disease. As a result of exposure to cholera, reports indicated that within three weeks 800 people died of the disease. Many of those that perished are buried in a common grave located at the Old City Cemetery located at 1000 Broadway Street in Sacramento. Approximately 80 physicians were working during the time of the cholera outbreak, and 17 died from cholera within a year after initial exposure (Old City Cemetery, 2005). What type of outbreak is this? Explain and include aspects of how exposure occurred, description of whether it is epidemic, pandemic, or endemic, type of exposure etc.

(a)The total water potential of an algal cell is -1.7MPa and solute potential within the cell is -2.6 MPa. The algal cell is placed in a large volume of 0.95 Molar sucrose solution at 20 celcius. will the water potential of the algal cell change? If so, what will be the new water potential? If solute potential does not change , what will be the new pressure potential?

(B) After the algal cell had equilibrated to the 0.95 Molar sucrose solution, it was then transferred to a larger volume of a 0.4 Molar NaCl solution at 30 celcius.What will be the new water potential of the algal cell after equilibrium? If solute potential does not change,, what will be the new pressure potential?

1. What are the intracellular junctions in plants and what do they do?

2.What are the intracellular junctions in animals and what do they do?

3.Why does a larger cell have to work harder to bring materials in and out of the cells.

4.Please draw a animal and plant cell with all organelles and write down what each
organelle does.

1. what is a saturated vrs unsatured phospholipid and what does it do
2.What is a alpha linkage and a beta linkage and which one would you find in Glycogen, Starch, and Cellulose?
3.How do cows digest Cellulose?
4.How are bacteria cells different than eukaryotic cells

5.What organelle(s) does the bateria and eukaryotic cells have in common?

6.What are the roles of the Cytoskeleton

7.Are the membranes separate in eucaryotes organelles?
8. How are rough and smooth ER different.

Discuss the Neutral Theory and describe how it has contributed to our understanding of evolutionary processes.

Assume you are analyzing the cell division process (mitosis and cytokinesis) in two individuals - a 10 year old male human and a 50 year old male human. Contrast the purpose of cell division and the locations where you would find cell division in these two individuals.

In the original implementation of PSI-BLAST, the algorithm performed a multiple sequence alignment and deleted all but one copy of aligned sequence segments having ≥ 98% identity. In a recent modification, the program now purges segments having ≥ 94% identity. What do you think would happen if this percentage were adjusted to ≥ 75% identity. How could you test this idea in practice?

(b) The following data was obtained from a study of an ecosystem in which 10 different species were randomly identified and their heights measured. As a Research Assistant for Plant Ecology Laboratory, determine:

(i) Mean height of all species combined

(ii) Variance as a measure of variability in plant height

(iii) Standard deviation

SPECIES HEIGHT(cm)

1. Beech (Fagus spp.) 300 cm

2.Hackberry (Celtis occidentalis) 90cm

3. Southern red oak (Quercus faclcata) 80 cm

4. Dogwood (Comus florid) 600 cm

5. Longleaf Pine (Pinus palustris) 2,450

6. Magnolia (Magnolia sp.) 1,250

7. Red Maple (Hacer rurua) 710

8. Shortleaf Pine (Pinus echinata) 1,350

9. Sweetgum (Liquidamba styracilua) 1,210

10. Wax Myrtle 1,150

11. Cabbage palmetto (Sabal palmetto) 60

12. Live oak (Quercus rubra) 2,055

13. Water oak (Q. nigra) 1,925

14. Scarlet oak (Q. coccinea) 1,075

15. Bald cypress (Taxodium distichum) 996

16. Black hickory (Carya sp.) 878

17. Black oak (Q. macrocarpa) 1,225

18. Wild Blackberry (Prunus serotina) 1,027

19. Eastern Cottonwood (Populus deltoides) 800

20. Virginia pine (Pinus virginiana) 1,330

c) Given the data as indicated above,

(i) Is this a predominantly terrestrial or aquatic ecosystem? Why?

(ii) Would you consider this a mixed hardwood/pine ecosysyetm?

(iii) Which plant species form the overstory of this ecosystem?

(iv) Is this a stable community?