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Human Biology

Volume & Concentration Problem is asssessed.

I have 100mls of an antibiotic stock solution at a concentration of 6mg/ml. I would like a final volume of 10mls of the antibiotic at a concentration of 1.5mg/ml. How much of the stock solution do I need to obtain this?

Dilution Series

I am looking for a detailed solution and explanation. I give you 10mls of an overnight culture of Micrococcus luteus at a concentration of 4.7 x 10^7 CFU/ml. Diagram a dilution series by using tubes containing 9ml nutrient broth (NB) and fixed-volume 1ml pipettes (won't measure any more or less than 1ml).

Dilution Series

Perform a 2-fold serial dilution using 4 tubes containing 1ml of NB each and a 20ml broth culture of Bacillus subtilis; use the same B. subtilis culture and perform a 2-fold serial dilution using 4 tubes containing 2ml of NB each; repeat in a similar fashion using 4 tubes containing 0.5ml each.

Dilution Series

I give you a very expensive strain of E. coli containing 10^12 CFU/ml and tell you that I need exactly 10ml of the same E. coli culture at a concentration of 10^4 CFU/ml (I don't want any excess culture). Using a dilution series, how would you get the correct concentration and volume of bacteria? Make this a realistic scenario.

Reproductive strategies, the human population, population growth

Identify the two most extreme types of reproductive strategies and make a distinction between the traits that would characterize these extremes. Give an example of an organism that illustrates each strategy. Identify the major problems anticipated with the increase in the human population in the 21st century and explain why i

Define and identify the relationship that the following have with stress

I started to answer these could you please help me ? C. Define and identify the relationship that the following have with stress: Epinephrine: A hormone secreted by the adrenal medulla. Epinephrine plays a central role in the short-term response to stress reaction. It is the physiological response to threatening excitemen

The combination of atoms in molecules

The combination of atoms in molecules depends in large measure on the a) Number of neutrons b) Placement of electrons in the shells c) Presence of organic matter in the environment d) Proton configuration of the nucleus

Help with micro question

Can you please confirm my choices for the below question? 1. A denatured protein is one that a. Has lost its three dimensional structure. b. Has reverted to a carbohydrate. c. Lacks amino acids. d. Lacks covalent bonds. My choice is (D) 2. Ions and atoms of an element differ in the a. Number of electrons they posse


1. IS THIS SCIENCE? Promotional materials for a sports drink say that "water is not enough" for people who are exercising and that it's important to instead consume a liquid that contains flavoring, carbohydrates, potassium and sodium. Do you think that consuming a sports drink after exercise can help maintain homeotasis? E

Topic: Smoking( see full description)

Topic: Smoking The topic must relate to the human body and contain in the following: 1. Introduction stating issue/problem and opinion/stance on this issue. 2. Main body- history/background supporting documentation, opposing Opinions, pros/cons. 3. Summary 4. Bibliography (at le

Muscle biopsies and functions of the cytoskeleton

3. If muscle biopsies (sample of tissue) were taken from the legs of a world-class marathon runner and a typical couch potato, which would you expect to have higher density of mitochondria? Why? How would the density of mitochondria in a muscle biopsy from the biceps of a weight lifter compare with those of the runner and th

Provide solution

Consider the consequences if a large meteor were to impact with Earth. What characteristics would be essential for survival ? What types of characteristics would be detrimental? What would have to be preserved in order to establish a diversity of life? What are the implications on evolution? What is your predic

'What would the world be like if solid water (ice) was denser than liquid water?

One of the science fiction magazines is having a call for conference topics. You decide to submit the following topic: ''what would the world be like if solid water (ice) was denser than liquid water?" Create a brief synopsis and include a brief discussion on the following issues: how you think the world would be diffe

Role of fungi in forests

If all the fungi were removed from our Pacific Northwest Forests how would that change our forests? (brief but thorough)


Can you tell me two similarities and two differences between the fMRI scan and an animal model?


What is a 'target' and how does it exert an effect on axons at a distance? Can you give me examples of targets and the area of the cells that is targeted?

Serial dilution problem

You have decided to determine how many microbes are living on the lettuce in the salad bar at your favorite restaurant. You place 1 gram of lettuce and 99 mls of water in a blender and blend the mixture. This is sample A. You then transfer 1 ml of this dilution into to another that contains 9 mls of water. This becomes sampl

Circulatory and Lymphatic System

Lymphatic system 1. Bean shape lymphatic organs found along lymphatic vessels are called... a. lymph nodes b. medullary cords c. germinal centers d. cistema chili 2. In innate immunity a. each exposure is very specific b. previous exposure are remembered c. each exposure elicits approximately the same type of respon

Identifying unknowns

If we are given a mixed broth tube with 2 unknowns, how will you isolate it? How will you know when it's isolated? Is it fair to say, that "Using sterile technique, I would preform the streak plate method. Once I can see, the 2 separate colonies in quadrant 4 of streak plate, I would put one of each colony into their own ag

Gulf of Mexico problem

(See attached file for full problem description with proper symbols) 1A. An island in the Gulf of Mexico is approximately circular, with a radius of 5 kilometers. There is no emigration or immigration. In a mark-recapture study of an anole population, 115 anoles were captured, marked, and released. In a second capture, 175 s

On Energy

Can you help put me on the right track with these? Many biological reactions proceed at far too slow a rate to make them metabolically effective. Is it the presence of enzymes that lowers the activation energy so that these reactions can take place? If not, then what? ATP is considered a short-term form of energy for a

Sugar is explored.

This job provides me with a simple explanation for how eating too much sugar makes us fat.

Rigor mortis

1. After death, the muscles of the body become very stiff and inextensible. This phenomenon is referred to as rigor mortis, and the muscles are said to be in a state of rigor. (a) Explain the biochemical basis of rigor mortis, in terms of the interaction of actin and myosin; ie, where in the contraction cycle is the

Problem Set

1 FSH stimulates the production of estrogen in this gland. 2 Functions in setting biological rhythms. 3 Produces and secretes testosterone. 4 Produces glucocorticoids. 5 Facilitates maternal behavior in mammals. 6 This hormone stimulates the release of two hypothalamic hormone. 7 A surge in this hormone triggers ovul

A test of semantic similarity is simulated.

1a) In a test of semantic similarity and at a target stimulus duration of D -10ms, which of the words 'bird' and 'fish' would be the most likely choice (give approximate %) in response to presentation of the target word 'hen'? This job explains the answer with reference to figure 4.3 below. 1b) In a test of semantic simila


If a patients suffers a complete transection at T12 of the spine what would be the resulting effect on their arms and legs?


1.What is the three main types of microbiological culture media? Why are Petri dishes inverted after they cool? 2.Which are of a streak plate will contain the greatest amount of growth? The least amount of growth? Why?

Ulcerative colitis

Gas sample taken from the lumen of the large instestine of person suffering from the disease ulcerative colitis were founf to contain 100 times the level of NO as compared to those taken from controls. What does this tell you about the probable nature of the disease?

What is a superantigen?

Looks at what superantigens are and why they are produced by some pathogens. Inlcudes examples.