It's called your Petella, although I don't know if that's how it's spelled.
Living organisms obtain many of their requirements by diffusion. They also get rid of many of waste materials in this way. For example, Plants need carbon dioxide for photosynthesis. This diffuses from the air into the leaves through the stomata. It does this because there is a lower concentration of carbon dioxide inside the leaf as the cells are using it up. Outside the leaf in the air, there is a higher concentration. Carbon dioxide molecules therefore diffuse into the leaf down this concentration gradient :)
I hope u understood!
Your answer is...
<em>A benign tumor is a noncancerous group of cells that does not spread any harmful substances to the impacted area nor anything at all. It is safe compared to Malignant tumors and typically cause no harm to the body.</em>
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Benign tumor:
Although it is noncancerous, if it is applying pressure to any vitals such as the blood vessels or nerves, it causes an obstruction. Thus ending up having to require treatment occasionally but not in all cases. It is considered a "good" tumor since it does not cause any pain or any problems when it doesn't apply pressure.
Malignant Tumor:
A Malignant Tumor is known as cancerous, or just cancer. These can be spread around the affected area of tissue or throughout the body. It is uncontrollably spread and disease ridden tumor that destroy the body tissue of the person. If this moves into the bloodstream, it can lead up to spreading within the lymph nodes, causing even more damage.
Answer: could you tell me the methods and its discription?
<h2>Differential test</h2>
Explanation:
A differential test helps to distinguish that which species lack or have the particular biochemical process,the three differential test media are:
1) Blood agar: Blood Agar is an enriched medium which is used to culture those bacteria or microbes that do not grow easily
- It is also required to detect and differentiate haemolytic bacteria, especially Streptococcus species
- It is also a differential media in allowing the detection of hemolysis (destroying the RBC) by cytolytic toxins secreted by some bacteria, such as certain strains of Bacillus, Streptococcus, Enterococcus and Staphylococcus
2) Eosin methylene blue agar (EMB): It is a selective and differential medium used to isolate fecal coliforms
- Eosin methylene blue are pH indicator dyes which combine to form a dark purple precipitate at low pH; they also serve to inhibit the growth of most Gram positive organisms
- Sucrose and lactose serve as fermentable carbohydrate sources which encourage the growth of fecal coliforms and provide a means of differentiating them
3) Mannitol Salt Agar (MSA): It is a selective and differential medium
- The high concentration of salt (7.5%) selects for members of the genus Staphylococcus, since they can tolerate high saline levels
- Organisms from other genera may grow, but they typically grow very weakly
Three examples of tests which are done on colonies are:
1) Catalase test: Catalase is an enzyme that breaks hydrogen peroxide (H2O2) into H2O and O2
- Hydrogen peroxide is often used as a topical disinfectant in wounds, and the bubbling that is seen is due to the evolution of O2 gas
- A small amount of growth from the culture is placed onto a clean microscope slide
- Few drops of H2O2 onto the smear is added
- A positive result is the rapid evolution of O2 as evidenced by bubbling
- A negative result is no bubbles or only a few scattered bubbles
2) Indole test: The main requirement for a suitable indole test medium is that it contain
s a sufficient amount of tryptophan
- Tryptone broth is commonly used
- The tube of tryptone broth with a small amount of a pure culture is inoculated
- Incubation is done at 35°C (+/- 2°C) for 24 to 48 hours
- To test for indole production, 5 drops of Kovács reagent is directly added to the tube
- A positive indole test is indicated by the formation of a pink to red color in the reagent layer on top of the medium within seconds of adding the reagent
- If a culture is indole negative, the reagent layer will remain yellow or be slightly cloudy
3) Urease test: Urease is a constitutively expressed enzyme that hydrolyzes urea to carbon dioxide and ammonia
- The urease test identifies those organisms that are capable of hydrolyzing urea to produce ammonia and carbon dioxide
- Urease test media contain 2% urea and phenol red as a pH indicator
- An increase in pH due to the production of ammonia results in a color change from yellow (pH 6.8) to bright pink (pH 8.2)
- Urea broth is a highly buffered medium requiring large quantities of ammonia to raise the pH above 8.0 resulting in a color change
