B looks like the best to me
What’s the rest of the question
Answer:
12:3:1
Explanation:
<em>The typical F2 ratio in cases of dominant epistasis is 12:3:1.</em>
<u>The epistasis is a form of gene interaction in which an allele in one locus interacts with and modifies the effects of alleles in another locus</u>. There are different types of epistasis depending on the type of alleles that are interacting. These include:
- Dominant/simple epistasis: Here, a dominant allele on one locus suppresses the expression of both alleles on another locus irrespective of whether they are dominant or recessive. Instead of the Mendelian dihybrid F2 ratio of 9:3:3:1, what is obtained is 12:3:1. Examples of this type of gene interaction are found in seed coat color in barley, skin color in mice, etc.
- Other types of epistasis include <em>recessive epistasis (9:3:4), dominant inhibitory epistasis (13:3), duplicate recessive epistasis (9:7), duplicate dominant epistasis (15:1), and polymeric gene interaction (9:6:1).</em>
Answer:
Explanation:
Carbon monoxide (CO) is a colourless, non-irritant, odourless and tasteless toxic gas. It is produced by the incomplete combustion of carbonaceous fuels such as wood, petrol, coal, natural gas and kerosene. Its molecular weight is 28.01 g/mol, melting point −205.1 °C, boiling point (at 760 mmHg) −191.5 °C (−312.7 °F), density 1.250 kg/m3 at 0 °C and 1 atm and 1.145 kg/m3 at 25 °C and 1 atm, and relative density (air = 1) 0.967 (1,2). Its solubility in water at 1 atm is 3.54 ml/100 ml at 0 °C, 2.14 ml/100 ml at 25 °C and 1.83 ml/100 ml at 37 °C.
The molecular weight of carbon monoxide is similar to that of air (28.01 vs approximately 29). It mixes freely with air in any proportion and moves with air via bulk transport. It is combustible, may serve as a fuel source and can form explosive mixtures with air. It reacts vigorously with oxygen, acetylene, chlorine, fluorine and nitrous oxide. Carbon monoxide is not detectable by humans either by sight, taste or smell. It is only slightly soluble in water, blood serum and plasma; in the human body, it reacts with haemoglobin to form carboxyhemoglobin (COHb).
The relationship of carbon monoxide exposure and the COHb concentration in blood can be modelled using the differential Coburn-Forster-Kane equation (3), which provides a good approximation to the COHb level at a steady level of inhaled exogenous carbon monoxide.
Conversion factors
At 760 mmHg and 20 °C, 1ppm = 1.165 mg/m3 and 1 mg/m3 = 0.858 ppm; at 25 °C, 1 ppm = 1.145 mg/m3 and 1 mg/m3 = 0.873 ppm.
<span>Natural selection is what allows a population to adapt because the animals that adapt are the ones that mate and pass along their genes. Without natural selection, evolution or adaptation would not be able to occur.</span>
