Naked mole rats were recently discovered to be able to survive 18 minutes of an anoxic (0% oxygen) environment without any difficulty. In 1976, the naked mole rat hemoglobin was studied and compared to that of mice and found to have higher oxygen affinity. The data below are representative of this study.

Table 1: Whole blood from each organism was assayed at pH 7.4 for oxygen affinity at two different temperatures. The P₅₀ is reported at each condition in the table.

Naked mole rats have a body temperature of 30-32°C, which is lower than the 37°C body temperature of most other mammals including Mus musculus.

A. Quickly look up data regarding the solubility of oxygen in water versus temperature. Does body temperature alone explain the greater oxygen binding capacity of Heterocephalus glaber compared to Mus musculus?

B. What do these p50 values indicate about the oxygen binding capacity of Heterocephalus glaber hemoglobin compared to Mus musculus hemoglobin?

C. Furthermore, the amount of 2,3-BPG in each organism’s bloodstream was assayed. [2,3-BPG] in Heterocephalus glaber was found to be 7.3mM and for Mus musculus, 7.4mM. Additionally, when hemoglobin from each organism was stripped of any ligands and then assayed for oxygen binding, the p50 for Heterocephalus glaber was found to be 8.0mmHg and the p50 for Mus musculus was found to be 11.3mmHg. What do these data tell you about the mechanism by which the affinity of each organism’s hemoglobin differs?

D. The protein sequence for the b-subunit of the naked mole rat hemoglobin is as follows:

HLSNE EKAAV TSLWG KVNVE ETGGE ALGRL LVVYP WTQRF FEHFG DLSSP SAIMG NPKVK AHGAK VLASF SEGLN HLDNL KGTFA KLSEL HCDKL HVDPE NFRLL GNVIV IVLAH HHGHD LTPTV QAAFQ KVVAG VAHAL GHKYH

Note that the actual structure of hemoglobin or the actual protein and mRNA sequences of other subunits of hemoglobin in the naked mole rat have not been studied. The mRNA information available is predicted from genome sequencing efforts, but has not been experimentally verified or studied.

What is the significance of the shaded amino acids? Hint, use your book. Are there any major differences in the two sequences that might explain the phenotype? Do not spend too much time agonizing over this.

Answer the question in regards to Botany;

Distinguish among the biological, morphological, and phylogenetic species concepts.

Distinguish between allopatric and sympatric speciation.

Briefly describe the processes of allopolyploidy, autopolyploidy, and recombination speciation.

1. Two homozygous strains of white-flowered bluebonnets are mated, the F1 offspring all have white flowers. The F1 plants are crossed to each other, 126 white-flowered and 33 blue-flowered plants were produced. Which of the following best describes the genotype of a homozygous blue-flowered plant?

2. From the F2 offspring in Question1, you cross two white flowered plants to each other. Half of their offspring have white flowers and half have blue flowers. What are the genotypes of the two white-flowered F2 plants?

The cell membranes of mammalian red blood cells are permeable to urea. If red blood cells are dropped into a solution of urea that is identical in osmotic pressure (isosmotic) to the cytoplasm of the cells, although the cells do not swell and burst as quickly as when they are dropped simply into pure water, they eventually swell and burst. Explain. Also discuss how you would design a solution into which red cells could be placed without ever swelling. (Hint: Think about whether urea will stay on the outside of the cells and the implications for osmotic pressures.)

Answer the Questions in regards to Botany;

How did Darwin’s observations and readings lead him to discover the theory of evolution by natural selection?

Describe the five conditions of a population in Hardy-Weinberg equilibrium.

Describe the following agents of change that cause deviation from Hardy-Weinberg equilibrium: mutations, gene flow, genetic drift, and natural selection.

Describe evidence for evolution.

Explain how the rate of glucose transport across cell membranes can be altered without a change in the external glucose concentration at which V1/2 and Vmax are measured. Explain what cellular changes can alter the external glucose concentration at which V1/2 is measured

Describe the chemical composition of each structures below. (Note that the chemical composition for many of the structures listed is a phospholipid bilayer.)

cell wall

chromatin

cytosol-

chloroplasts

chromoplasts

cytoskeleton

Golgi apparatus

leucoplasts

mitochondria

nuclear envelope

plasma membrane

peroxisomes

ribosomes

rough endoplasmic reticulum

smooth endoplasmic reticulum

tonoplast

PLEASE ANSWER ALL PARTS FULLY!

How did the Meselson & Stahl’s experiment allow the investigators to distinguish between the 3 overall methods of DNA replication? What approaches were used in investigating the enzymology of DNA replication, remembering that studying an essential function presents a particular challenge?

Your lab is studying gene expression of the tryptophan operon in the bacterium E. coli. In order to facilitate this study, you have cloned the Trp-operon, excised the five coding genes (TrpA, B, C, D, and E), and replaced them with a copy of the reporter gene GFP (green fluorescent protein). The resulting recombinant DNA was inserted into an F' plasmid, and used to transform a number of different strains of E. coli. For each of the scenarios listed below, predict what the bacterial colonies would look like, and explain why you would obtain these results.

a. A "wild type" strain of E. coli, transformed by the F' Trp/GFP reporter plasmid, is plated out on a selective medium lacking tryptophan.

b. A "wild type" strain of E. coli, transformed by the F' Trp/GFP reporter plasmid, is plated out on tryptic soy medium.

c. A trpR mutant strain of E. coli, transformed by the F' Trp/GFP reporter plasmid, is plated out on tryptic soy medium.

You discover a mutant yeast strain that cannot grow when provided with pyruvate as its sole carbohydrate, although it grows normally when given glucose as a carbon energy source; you call this the Pyr– trait. Wild-type yeast can grow well using either carbon source; you designate this the Pyr+ trait. You suspect that the mutant yeast have defective mitochondria.

A. Why is mitochondrial function critical for growing on pyruvate?

B. You want to determine whether the mutation responsible for the Pyr– trait is carried in the nuclear or mitochondrial genome. Your experiment is to mate Pyr– haploid cells to Pyr+ haploid cells and examine segregation of the trait in the progeny. After mating, the Pyr-/Pyr+ diploid cells can grow on pyruvate (Pyr+). You send these diploid cells through meiosis and examine the four haploid cells generated from a single diploid cell. If the mutation is in mitochrondrial DNA, will the four haploid cells probably be all Pyr–, all Pyr+, or a combination? What if the mutation is in nuclear DNA?

what would happen to the charge across the cell membrane outside cell potassium concentrations are greatly increased by KCL injection into the blood

In a population where skin color gene can be determined by 4 alleles B(black)=0.412561 o(olive) = 0.312450 y(yellow) = 0.112689 w(white) =0.123540. The gene for skin type can be determined by 3 alleles N(normal)=0.425789 d(dry)= 0.345689 x(oily)=0.214130. The gene for skin elasticity can be determined by 2 alleles E(elastic)= 0.456820 and e(non-elastic)= 500123. Assume Hardy-Weinberg equlibrium, what is the frequency of getting yellow, normal, elastic skin? (p² + 2pq + q² + 2pr + 2qr + r² = 1). ?