Daily NEET MCQ- June 6, 2022 - NEET MCQ

Instantaneous velocity describes the velocity of an object at a given time instant. Average speed is the speed at which the object travels throughout the time period and not an instant. Speed is a scalar quantity; hence it cannot show the direction of motion.

The function for velocity can be derived by differentiating the equation with respect to t. v = 2(t-4) is the required function. When t = 5, v = 2(5-4) = 2.

The instantaneous velocity will increase with time. If the motion is accelerated, no matter if the acceleration is constant, or variable, the instantaneous velocity will increase. Variation of acceleration describes how to change in velocity is changing.

Prior to World War II, many naturally occurring chemicals such as nicotine were used as pest controlling substances for major crops in agricultural practices. This was achieved by planting tobacco plants in the crop fields.

During World War II, DDT was found to be of great use in the control of malaria and other insect-borne diseases. Therefore, after the war, DDT was put to use in agriculture to control the damages caused by insects, rodents, weeds, and various crop diseases. However, due to adverse effects, its use has been banned in India.

These days, the pesticide industry has shifted its attention to herbicides. During the first half of the last century, this shift from mechanical to chemical weed control had provided the industry with flourishing economic market.

Megasporangium in Gymnosperms is also called as Nucellus. It contains megaspores or macrospores which gives rise to a female gametophyte or archegonium after mitosis.

In cycas, the type of root present is called coralloid root. Coralloid roots are short and irregularly branched. They exist in symbiotic association with cyanobacteria that help them in fixation of Nitrogen.

Gymnosperms range from small shrubs to tall trees. In fact, red wood tree is the tallest tree in the world. They are evergreen, perennial and woody trees and are mostly found in California.

Phanerogams contain specialized reproductive organ and don’t follow cryptogamae. Phanerogams are classified as Gymnosperms and Angiosperms based on the type of seed they produce. Gymnosperms have naked seeds and Angiosperms have covered seeds. Angiosperms bear fruit whereas Gymnosperms don’t.