Where do these metals originate? Science students were tasked with completing the Venn diagram to distinguish between natural occurrences and occurrences due to human activities. There was great debate among the students. Can you help them out? Where should these metals be placed and
why?
A) Heavy metals occur naturally in underground rocks and soils and leach into groundwater.
B) Human activities such as mining and construction can release large amounts of heavy metals into nearby ground water sources.
Increased urbanization and the associated human activities are to blame for an increased levels of heavy metals, in our waterways.
Heavy metals occur both naturally and as a result of human activities. They occur natural in rocks and soil and are the by-products of
D)
a multitude of human activities

what have scientists found to be the most efficient and effective way to insert new sequences into an individual? a-scientists have created genetically altered foods that release dna during digestion. b-scientists use viruses to insert specific gene sequences. c-scientists irradiate genes so that they can be absorbed through the skin.

volcanoes (an event in the geosphere) release a large amount of particulate matter into the atmosphere. these particles serve as nuclei for the formation of water droplets (hydrosphere). rainfall (hydrosphere) often increases following an eruption, stimulating plant growth (biosphere).

all these collisions do one thing, and that thing is explained in the last option. when dusst, rocks and ice collide, they harden and form giant layers of rocks or hard ice.

d)   to harden materials to form different parts of earth’s layers

hope it ,

bioteacher101