TECHNICIAN 2 IS CORRECT.
Wheel bearing is typically used for guiding and supporting shafts and sometimes axles. Wheel bearing has its own special grease, which is specifically designed for high friction surfaces. Most bearing wheels in cars and trucks are typically lubricated with NLGI {National Lubricating Grease Institute] Number 2. Effective lubrication is needed to ensure that a wheel bearing has a long life.
Answer:
Invasive plant species have an impact on the diversity of local species, they affect water availability and damage the quality of soil nutrients. Once an alien plant has invaded a habitat, it changes the conditions of that environment. It does so by changing the light, solar radiation and temperature levels in the invaded patches. The quality and availability of food, shelter, nest sites, basking sites and perches are changed for a number of animals.In a few cases, some benefits of alien plants have been reported. For example, they can provide fire wood for local communities or add resources for animal species. But these benefits typically do not surpass the negative effects.
Explanation:
This response is important because it enables the plant to increase its intake of carbon dioxide. Carbon dioxide is an important gas,during the process of photosynthesis, where plants use energy from sunlight to make simple sugars and release oxygen. This is also a way of absorbing carbon dioxide (a green house gas) from the atmosphere thus reducing its amounts.
Definition
A technique which is used to separate, DNA, RNA or protein pieces from each other under the influence of electric field on the basis of their molecular size is known as gel electrophoresis.
Explanation
This method is very reliable for separation of large size molecule (over 1 million Da). Materials which are required for gel electrophoresis include:
1. TAE stock buffer
2. 1% agrose gel
3. Nucleic acid loading dye
4. Ethidium bromide
Procedure:
First prepare a stock solution of TAE buffer by adding appropriate amount of TAE in distilled water. then prepare 1% agrose by adding 1X TAE, some amount of agrose in water and heating it in microwve oven to mix them will. then pour agrose gel on tray and fix comb in it and keep it untill agrose dry. Then remove comb and pour some quantity of nucleic acid along with loading dye and ethidium bromide in each well. EtBr is used for staining nucleic acid.
When sample is poured in all well also pour reference marker in one well for comparison. now connect it with voltage for 30-35 min. After this take gel and see it under UV. a large number of nucleic acid pieces will be seen on gel under UV. those pieces which have small molecular weight will cover more distance compared to those having larger molecular weight.
