Answer:
The distance between them is changing at the speed of 10.16 m/hr
Explanation:
Consider the sketch attached below.
The question is simply asking to calculate the resultant of the two velocities.
To get the angle between them, we simply use the coordinates of the two vectors to determine the angle between them.
90 + 45 = 135°
from the cosine rule we have
= 
+ 
- 2abcosθ
= 
+
- 2 ×6×5×cos 135
= 103.426
c = 
c = 10.17 m/hr
Answer:
Option a is the one, that is true.
Sister chromatids separate in anaphase of mitosis and anaphase Il of meiosis
Explanation:
After the interphase in the cell division cycle, the mitosis process begins, which is composed of 4 phases, prophase, metaphase, anaphase and telophase. The prophase occurs when the chromatin is condensed and the mitotic spindle is formed, the metaphase the chromosomes align along the cell equator, in the anaphase the separation of the sister chromatids occurs and in the telophase finally the heterochromatin is converted into euchromatin and the envelope is formed nuclear cell.
Meiosis, which is the cell division of germ cells, also has the same phases but they occur on two occasions: prophase I, metaphase I, anaphase I and telophase I for meiosis I and for meiosis II, prophase II, metaphase II, anaphase II and telophase II. In the anaphase I the homologous chromosomes are separated, they are condensed in the prophase II while in anaphase II the chromatids are separated.
<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
Answer:
The rate of photosynthesis increases the intensity of light or concentration of CO2 increases, however, at a certain temperature, the rate can decrease due to enzyme denaturation.
Explanation:
Photosynthesis is a unique metabolic process specific to only some organisms. The photosynthetic process, however, cannot occur without some vital ingredients including light, Carbon dioxide (CO2) and optimum temperature.
An increase in the concentration of light (from sun) and CO2 (from atmosphere) increases the rate at which photosynthesis occurs i.e. more light, CO2 results in more photosynthetic process. However, an increase in TEMPERATURE also increases the photosynthetic rate but at a particular temperature, the enzymes that bring about the photosynthetic process can be denatured or damaged, hence, at an EXCESSIVE TEMPERATURE, photosynthesis can be inhibited.
