The main constituent of alcohol is Ethanol and the concentration of ethanol in a sample can be determined by back titration with acidified potassium dichromate. Reacting the sample with an excess of potassium dichromate, all ethanol is oxidized to acetic acid. One major application for this reaction is in old police breathalyzer tests. When alcohol vapor makes contact with the yellow dichromate-coated crystals, the color changes from yellow to green. The degree of the color change is directly related to the level of alcohol in the suspect’s breath.

Correct Option: A

The main constituent of alcohol is Ethanol and the concentration of ethanol in a sample can be determined by back titration with acidified potassium dichromate. Reacting the sample with an excess of potassium dichromate, all ethanol is oxidized to acetic acid. One major application for this reaction is in old police breathalyzer tests. When alcohol vapor makes contact with the yellow dichromate-coated crystals, the color changes from yellow to green. The degree of the color change is directly related to the level of alcohol in the suspect’s breath.

AIDS viruses have single stranded RNA. It is composed of two copies of positive single-stranded RNA that codes for the virus’s nine genes enclosed by a conical capsid composed of 2,000 copies of the viral protein. The single-stranded RNA is tightly bound to nucleocapsid proteins.

Correct Option: A

AIDS viruses have single stranded RNA. It is composed of two copies of positive single-stranded RNA that codes for the virus’s nine genes enclosed by a conical capsid composed of 2,000 copies of the viral protein. The single-stranded RNA is tightly bound to nucleocapsid proteins.

Wavelength of light between 400 nm and 700 nm is most effective for photosynthesis. This light is called photosynthetically active radiation (PAR). Comparatively more photosynthesis occurs is red and blue regions though others have significant net photosynthesis. Light has maximum efficiency in red and minimum in blue region. In both these regions light is absorbed by chlorophyll. Red light favours more carbohydrate accumulation while blue light favours more protein synthesis.

Correct Option: A

Wavelength of light between 400 nm and 700 nm is most effective for photosynthesis. This light is called photosynthetically active radiation (PAR). Comparatively more photosynthesis occurs is red and blue regions though others have significant net photosynthesis. Light has maximum efficiency in red and minimum in blue region. In both these regions light is absorbed by chlorophyll. Red light favours more carbohydrate accumulation while blue light favours more protein synthesis.

If we look at the dermis, the layer on the skin beneath the epidermis (outer layer), and a certain type of cell within this layer, called a fibroblast, we find that the fibroblasts in the soles and palms secrete higher levels of a protein known as dickkopf 1, or DKK1, than the fibroblasts in the dermis at other body sites. It is believed that the rich source of DKK1 in these areas affects the epidermal layer above it and creates the physical characteristics of thickened, paler skin. DKK1 thickens the epidermis by increasing the number of skin cells and their density. Three genes affected by DKK1 – keratin 9, a KLEIP and a-catenin – have been found to cause this thickening. Keratin 9 reinforces the skin against physical impact, aKLEIP aids in cell division (multiplying) and makes cells smaller and, finally, a reduction in a-catenin is also possibly involved in cell contraction (making the cells more compact).

Correct Option: D

If we look at the dermis, the layer on the skin beneath the epidermis (outer layer), and a certain type of cell within this layer, called a fibroblast, we find that the fibroblasts in the soles and palms secrete higher levels of a protein known as dickkopf 1, or DKK1, than the fibroblasts in the dermis at other body sites. It is believed that the rich source of DKK1 in these areas affects the epidermal layer above it and creates the physical characteristics of thickened, paler skin. DKK1 thickens the epidermis by increasing the number of skin cells and their density. Three genes affected by DKK1 – keratin 9, a KLEIP and a-catenin – have been found to cause this thickening. Keratin 9 reinforces the skin against physical impact, a KLEIP aids in cell division (multiplying) and makes cells smaller and, finally, a reduction in a-catenin is also possibly involved in cell contraction (making the cells more compact).

Cloves are the aromatic dried flower buds of a tree in the family Myrtaceae. The clove tree is an evergreen that grows to a height ranging from 8–12 m, having large leaves and sanguine flowers in numerous groups of terminal clusters. The flower buds are at first of a pale colour and gradually become green, after which they develop into a bright red, when they are ready for collecting.

Correct Option: C

Cloves are the aromatic dried flower buds of a tree in the family Myrtaceae. The clove tree is an evergreen that grows to a height ranging from 8–12 m, having large leaves and sanguine flowers in numerous groups of terminal clusters. The flower buds are at first of a pale colour and gradually become green, after which they develop into a bright red, when they are ready for collecting.