Horses have 64 chromosomes and donkeys 62. The sterile hybrid between a horse and donkey is called a mule. In 1985 a mule named Krauss gave birth to foal named Blue Moon who was also a mule, and then in 1987 to another mule foal named White Lightning. Krauss was routinely pastured with other mules and horses but not donkeys. Explain this unusual occurrence.

4. Termination of replication in prokaryotes

5. Which of the following statements regarding r RNA is correct:

a) The most common of all RNA structures

b) It comes in the form of a single-chain molecule

c) It comes in the form of a double-stranded molecule

d) The structure contains a large number of loops, loops and bubbles

e) It comes in the nucleus of the cell

6. The characteristics of m RNA synthesis are:

a) takes place in the nucleus of the cell

b) takes place in the cytoplasm of the cell

c) nucleotides are linked by phosphodiester bonds

d) takes place on the DNA coding strand

e) energy from the hydrolysis of pyrophosphate is required for the process of m RNA biosynthesis

7. Leucine - zipper proteins

8. Lac operon

9. The significant difference between prokaryotes and eukaryotes is as follows:

a. Prokaryotes do not have DNA, as genetic material, while eukaryotes have

b. Prokaryotes do not have ribosomes, while eukaryotes have

c. Prokaryotic cells are not membrane-bound, whereas eukaryotic ones are

d. Eukaryotic DNA floats freely in the cell, while prokaryotic DNA is located in the cell nucleus

e. Nothing is true

You have ordered a set of enzymes that includes a protease, a DNase, and a RNase. Unfortunately, the company that you ordered them from failed to label the tubes with the specific enzymes and they are only labeled A, B and C. In your lab you have two strains of bacteria that are transformable. Strain Q is prototrophic but sensitive to the antibiotic streptomycin and strain R is auxotrophic for tryptophan but resistant to streptomycin. How might you devise an experiment to determine which tube contains DNase?

Glucose are stored as glycogen in muscle cells, from which it can again be mobilized during exercise.
a) Write down the partial reactions as well as the net yield for the conversion of glucose-6-phosphate to glycogen and for the conversion of glycogen to glucose-6-phosphate.
b) Calculate the energy required for the consumption of the total process of converting glucose-6-phosphate to glycogen and back to glucose-6-phosphate expressed as energy-rich phosphate bonds (ATP equivalents).
ΔG0’ for the reaction: ATP + H2O → ADP + Pi = –30.5 kJ∙mol-1.
c) Calculate ΔG’ for the reaction at 25 °C and pH 7, when [ATP] = 5 mM, [ADP] = 0.5 mM and [Pi] = 1.0 mM.
Phosphocreatin constitutes a small extra storage of energy within muscle cells, and is formed from phosphorylation of creatin. The reaction is catalyzed by creatine kinase and ΔG0’ for the reaction is +2.3 kJ∙mol-1 (progressing towared the formation of phosphocreatin).
d) Calculate how much phosphocreatin formed relative to creatin at equilibrium in the creatin kinase catalyzed reaction (assuming the same temperature, pH and concentrations of ATP and ADP as indicated in the previous question).

The protein synthesis in pro- and eukaryotic species resembles each other to a large degree. In both pro and eukaryotic cells, mRNA is used as template for incorporation of the correct amino acids in the growing polypeptide chain.
a) List the main differences between mRNA from prokaryotic and eukaryotic species
b) In contrast to prokaryotic cells, eukaryotic cells has spliceosomes, what function do they have? and list the main steps in the reaction
c) How many different codons code for amino acids?
d) Explain why the number of different tRNA molecules is lower, than the number of different codons?

The transport of Potassium across a eukaryotic membrane can happen by either a passive or an active transport. The active transport is used when Potassium has to move against the concentration gradient that is from a low concentration outside cells to a high concentration inside cells. Ion channels mediate the passive transport and these transport ions from a high concentration to a low concentration.
The Potassium channel is very selective for the transport of Potassium.
a) Explain how the selectivity of the potassium channel is ensured and why the smaller ion lithium will not be transported through the potassium channel.
The gene encoding the Potassium channel in eukaryotes is transcribed into a pre-mRNA.
b) List the three elements in a pre-mRNA in eukaryotes that is not found in a prokaryotic mRNA?
c) RNA polymerase II is responsible for the transcription of the gene encoding the Potassium channel; the carboxyl-terminal domain of the RNA polymerase II has a special function, describe the function?
d) Give the post-translational modification, which is responsible for the regulation of the activity of the carboxyl-terminal domain of RNA polymerase II.

The protein synthesis can be divided in three phases: initiation, elongation and termination.

a. Describe the initiation phase as it takes place in bacteria.

b. The initiation phase in pro- and eukaryotes begin differently, when it concern the recognition of mRNA, describe these differences.

c. tRNA transport amino acids to the ribosome. Which part of the tRNA molecule form a covalent link to the amino acid? And what is the name for the general class of enzymes that catalyse the formation of a covalent bond between tRNA and aminoacids?

d. Describe the mechanism which ensure that only the amino acid threonine is attached to threonyl-tRNA.

What do LDL receptor (LDLR) cytoplasmic domain mutations that cause familial hypercholesterolemia reveal about the receptor-mediated endocytosis (RME) pathway? Based on your knowledge of the entire endocytic process of LDL, are there other proteins in the pathway that if mutated might cause hypercholesterolemia? Explain how and why a mutation in a different protein in the pathway could cause disease. For a person who is homozygous for the NPXY mutation in their LDLR, can you think of a way to fix this individuals uptake of cholesterol?

for each generation, take 6 of the 10 alleles and give three to the deme on your left and three to the deme on your right. Conversely, add in three alleles from the deme on your left and three alleles from the deme on your right. Note that this requires that the entire class samples in unison.

Q8) How did the addition of gene flow affect genetic variation in your deme? Which model of gene flow (infinite island model or stepping stone) is most consistent with the pattern we simulated in class?

Why was Don Johanson's finding of the "First Family" so significant for resolving questions about Australopithecus afarensis?   

4. Together with a specific set of proteins, snoRNAs direct the meth- ylation or pseudouridylation of rRNAs. Does the snoRNA function as a scaffold, guide, ribozyme, blocker, decoy, and/or alterer of protein function or stability?

The following statement is FALSE.

Both eukaryotes and prokaryotes require a promoter region for gene translation.

(a) Identify the incorrect word(s).

(b) RE-WRITE the statement correctly.

i need help

During strenuous activity, the demand for ATP in muscle tissue is vastly increased. In rabbit leg muscle or turkey flight muscle, the ATP is produced almost exclusively by lactic acid fermentation. ATP is formed in the payoff phase of glycolysis by two reactions, promoted by phosphoglycerate kinase and pyruvate kinase. Suppose skeletal muscle were devoid of lactate dehydrogenase. Could it carry out strenuous physical activity; that is, could it generate ATP at a high rate by glycolysis? Explain.

Discuss the pros and cons of lactate production in active muscle. Why is lactate produced? What happens to the lactate?

The transformation of glucose to lactate in myocytes releases only about 7%
of the free energy released when glucose is completely oxidized to CO₂ and H₂O. Does this mean that anaerobic glycolysis in muscle is a wasteful use of glucose?

Question 6:

Calculate the genotypic frequencies that you would expect if the population is in Hardy-Weinberg equilibrium.

(Remember, that we are preparing to use the Chi-square goodness-of-fit test to determine if this population is in fact in Hardy-Weinberg equilibrium).

Round your answer to three decimal places and submit your answer in the correct format (e.g. 0.062).

(a) The frequency of the SS genotype is:

(b) The frequency of the Ss genotype is:

(c) The frequency of the ss genotype is:

The total number of leopards in this population is 284.

For reference:

S = dominant allele for brown pigmentation

s = recessive allele for red pigmentation (erythrism)

the frequency of the S (dominant) allele in this population: 0.916

the frequency of the s (recessive) allele in this population: 0.084