Answer:
Active uptake (which I think you mean active transport) is important when the concentration gradient is against that of a certain substance, so it doesn't cross the membrane through diffusion or passive transport. It is sometimes necessary if a substance needs to move across a membrane but can't do so due to electrical charge or that there is a substance on the other side of the membrane preventing diffusion.
Explanation:
Dust in the atmosphere represents suspension. It is collaborating shaped during colliding and collapsing of the interstellar mediums this is influenced by the gravitational attraction of the atoms and particles in the entitles. Hence, there are three types of nebular namely, are classical nebula, diffuse nebula, planetary nebular and supernova remnants.
Answer: a) Bacteria
Example of a disease caused by bacteria –
Tuberculosis (TB) is a kind of respiratory disease caused by bacterium called Mycobacterium tuberculosis.
B) Fungi
Example of a disease caused by Fungi
Athlete's foot is a fungal disease caused by Trichophyton (hopefully this helped)
The decay of uranium isotopes is used to provide information about the age of Earth.
<h3>
Explanation:</h3>
Isotopes of Uranium U-232, U-233 , U-234 , U-235 , U-236 , U-238 are used as fuel in nuclear reactors or as explosives for nuclear weapons. Uranium 238 is not very radioactive and it constitutes for nearly 99.3% of natural uranium on Earth and has the longest lifetime: its period is 4.5 billion years, about the age of Earth.
Use of radiometric dating techniques help in defining the age of substances (natural or man-made) using the known decay rates of radioactive elements. Each element has an individual decay rate and half life time.
Two Uranium isotopes (U-238 and U-235) are used for radiometric dating. Both the isotopes have different decay rates and half life period. Both are unstable and radioactive. Since two different isotopes produce two different decay clocks (one as a reference to other), it is beneficial in accurately determining the age of samples. The age of earth (rocks or other natural elements) can be easily determined using Uranium isotopes.
Answer:
Water pollution is one of the most common type of pollution that leads to the deterioration of the water quality mainly due to the man-made interference. Direct and indirect pollution are two of its types. Direct pollution as the term suggests refers to the direct flow of pollutants in the water in contrast to the indirect pollution that accounts for the transport of pollutants eventually to the water body.
Explanation:
Direct pollution is characterized by the release of toxic fluid directly in the water body. The main source of this type of pollution are the toxic pollutants from the large factories. Some of the other sources includes solid waste from the household activities and waste from agricultural practice like fertilizers, and the waste generated by the waste water treatment plant.