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Human Biology

An overview of spinal cord injuries is presented.

Discuss some of the challenges, possibilities and goals for treating spinal cord injuries. Please include the pros and cons behind treatment options (for example, stem cells as well as the information at the Christopher Reeve Foundation site).

Decline of synapses in the prefrontal and visual cortex

In the prefrontal cortex, what ages show the greatest rate of decline in synapses (can you give approx. number of synapses per age)? Same question for the visual cortex? What accounts for this synaptic rearrangement and why does it occur when it does?

Mice Genetic Experiment: Hypothesis Testing

One can create "knockout" mice that are missing a specific gene through a process called gene targeting. An investigator created such a mouse for a cell surface receptor expressed by the vast majority of B and T lymphocytes called Mel-14. After creating mice homozygous for this mutation (termed Mel-14-/-), she compared the numbe

Growth curve

Starting with four bacterial cells per milliliter in a rich nutrient medium, with a 1-hr lag phase and a 20-min generation time, how many cells with there be in 1L of this culture after 1 hour? After 2 hours? After 2 hours if one of the initial four cells was dead? Graph these growth curves with appropriate labels.

Discussion on various endocrinology questions.

This solution discusses four endocrinology questions: 1. List the four mechanisms involved in the regulation of aldosterone secretion. 2. Mr. Sanchez makes an appointment to see his doctor for pain in his abdominal area. Tests and x-rays reveal kidney stones as well as bones with a moth-eaten appearance. Further questionin

Duel-receptor vs. Altered Self models in T cells

The two proposed models of T-cell recognition are the Duel-receptor and Altered Self theories. We now know that thanks to the experimentation done by J.W. Kappler, the Altered Self model is the correct of the two. But suppose back before this was known, what sort of experiment could we maybe do in order to differentiate betwe

areal density and mean spacing

The area fraction associated with membrane proteins in the red blood cell (diameter = 8 µm) membrane is roughly 23%, while the lipids themselves take up roughly 77% of the membrane area. a.Approximately how many phospholipids make up the red blood cell membrane? b.How many membrane proteins would you estimate are in the r

Graft Versus Host Disease in twins debate

Please use at least 300 words to answer the following questions, and include references as part of your solution. Does Graft Versus Host Disease ever occur between identical twins? If so, what is the reasoning?

L. monocytogenes

1.) Discuss the zero tolerance policy for L. monocytogenes in the U.S. relative to the control policies in other countries.

E.Coli overview

1.) Summarize the characteristics of the strains of E. coli that are intestinal pathogens.

Transposition of the great vessels

What are the physiological consequences of this defect for Maria, a newborn baby, who needs surgery because she was born with an aorta that rises from the right ventricle and a pulmonary trunk that issues from the left ventricle, a position that is called transposition of the great vessels.

please help me understand the following dilution schemes

Consider the following dilution scheme: A. 1oomL lake water B. 5mL lake water into 45 mL diluent 0.1 ml - colonies TNTC C. 1mL from B into 9ml diluent 0.1 ml - colonies 425 D. 0.5mL from C into 4.5 mL diluent 0.1 ml - colonies 58 E. 2mL from D i

Biology Lab - Serial Dilutions and CFUs

One mL of yogurt was added to 99mL sterile diluent. Decimal (1/10) dilutionswere then made, and one-tenth mL was plated in duplicate on plate count agar. After incubation, the following colony counts were made: Dilution colony count using the data, calculate the # of cfu's per gram of the yogurt (1mL of yogurt = 0.4g) init

Characteristics of Inflammation

Is all inflammation the same or are there degrees of inflammation? And does inflammation differ if you have more bad (meaning pathogenic) bacteria hanging around?

Fungi as Human Pathogens

(1) Fungi as human pathogens (2) Fungi and their symbiotic role (3) Fungi in commercial applications.

Could someone please help with the following,please provide sources

(1) There are two circuits of blood flow to the body. Describe these two circuits in general terms. Beginning with the heart, which side of the heart pumps blood to each of the circuits? (2) A separate circuit involving the coronary blood vessels serves the heart. Describe the vascular route of coronary circuit, and suggest

Health Science

Your success at investigating the pattern of unusual student absences has led to your team being put in charge of the entire Health Department investigation. Your boss, the Director, has been working with school principals and parents and has sent you the following e-mail: http://science.education.nih.gov/Supplements/NIH6/inquir

Blood pressure regulation

Regulation of blood pressure including preload, afterload, hormones, and blood vessel arrangement. This is a Word document (.doc).

Antibiotic classes are reviewed

List of common antibiotic classes, mechanism of action, and examples. This is best used to review for a test. This is a Word document (.doc).

Rapid Population Growth and Consequences

World population growth is an often discussed topic. At one time, there was a fear of overgrowth and the book, The Population Bomb warned of doom and gloom. What are some key issues with a rapidly growing population?

Carbon Footprint and Nomadic Cultures

The carbon footprint left by people living in highly developed nations is astoundingly high. Some cultures, on the other hand, leave little, if any, carbon footprint. For instance, Nomadic cultures on many continents follow herds of migratory animals (e.g., the !Kung San of the Kalahari). Such people never settle permanently, an

Pathogenesis and skin micro flora (microbiata)

Many bacteria colonize human skin; these organisms are called the normal microbiata. Based on your knowledge of human skin, why do you think that these bacteria do NOT usually cause skin infections, yet can quickly cause infection when the skin surface is broken, as in a wound?

Characteristics of Selective and Differential Media.

Selective and Differential Media are both used in microbiological and clinical settings to aid in the identification of bacterial groups. List two specific media that have both selective and differential characteristics and specify the selective and differential agents in the media. Also describe how the results are interprete