Questions
Sickle-cell anemia is frequently described as affecting only Africans or people of African descent; it’s considered...

Sickle-cell anemia is frequently described as affecting only Africans or people of African descent; it’s considered a “racial” disease that doesn’t affect other populations. How would you explain to someone that this View is incorrect?

In: Biology

Answer the question in regards to Botany; Distinguish among the biological, morphological, and phylogenetic species concepts....

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.

In: Biology

Why are the principles of segregation and independent assortment key to understanding inheritance? How do these...

Why are the principles of segregation and independent assortment key to understanding inheritance? How do these principles differ from the theory of blending inheritance?

In: Biology

1. Two homozygous strains of white-flowered bluebonnets are mated, the F1 offspring all have white flowers....

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?

A/A; B/B

A/A; b/b

a/a; b/b

A/A; b/b or a/a; b/b

there are not enough data to tell

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?

A/A; B/B and a/a; b/b

A/A; b/b and a/a; B/b

a/a; b/b and A/A; B/b

A/A; b/b and A/a; b/b

there are not enough data to tell

In: Biology

The cell membranes of mammalian red blood cells are permeable to urea. If red blood cells...

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.)

In: Biology

Answer the Questions in regards to Botany; How did Darwin’s observations and readings lead him to...

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.

In: Biology

Explain how the rate of glucose transport across cell membranes can be altered without a change...

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

In: Biology

Describe the chemical composition of each structures below. (Note that the chemical composition for many of...

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

In: Biology

PLEASE ANSWER ALL PARTS FULLY! How did the Meselson & Stahl’s experiment allow the investigators to...

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?

In: Biology

Your lab is studying gene expression of the tryptophan operon in the bacterium E. coli. In...

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.

In: Biology

List and describe five distinct properties of biological membranes.

List and describe five distinct properties of biological membranes.

In: Biology

You discover a mutant yeast strain that cannot grow when provided with pyruvate as its sole...

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?

In: Biology

what would happen to the charge across the cell membrane outside cell potassium concentrations are greatly...

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

In: Biology

In a population where skin color gene can be determined by 4 alleles B(black)=0.412561 o(olive) =...

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). ?

In: Biology

Describe an example of where fossils have been used to reconstruct the behavior of extinct animals.

Describe an example of where fossils have been used to reconstruct the behavior of extinct animals.

In: Biology