Teratogens affect the fetus and not the mother because teratogens are "environmental exposures" done by the mother. It is an agent that can disturb the development of an embryo of fetus such as drugs or ingestion of harmful substances such as smoking and drinking. What happens is that the toxins are being ingested by the fetus through the umbilical cord where they are being supplied by oxygen and nutrition and instead of providing nutrients harmful substances are being ingested by a growing fetus.
The aboveground infrastructure—pads and access roads—are built, setting up the land for the next step: drilling. From start to finish, everything from traffic plans and designated access roads to noise barriers and safety procedures is carefully planned and monitored according to state and local laws.
STEP 2: DRILLING
First the drill rig is brought to the location—maybe 20 or 30 truck loads—and put together. Now It’s time to build the infrastructure necessary to unlock the oil and natural gas trapped more than a mile below the ground. A well is drilled straight down into the ground beneath the pad. The first stage is to drill what is called the surface hole down to a depth of 100 feet below the deepest known aquifer. A steel casing is then
Answer:
Why is it important to learn about stem cells and stem cell research?
Researchers hope stem cell studies can help to: Increase understanding of how diseases occur. By watching stem cells mature into cells in bones, heart muscle, nerves, and other organs and tissue, researchers may better understand how diseases and conditions develop.
How does stem cell research affect society?
Research with embryonic stem cells may lead to new, more effective treatments for serious human ailments and alleviate the suffering of thousands of people. Diseases such as juvenile diabetes, Parkinson's disease, heart failure and spinal cord injuries are examples.
