What Was Needed to Develop in Earth's Atmosphere to Protect

question 31

Multiple Choice

What was needed to develop in Earth's atmosphere to protect organisms from the harmful effects of ultraviolet radiation?

• A) weather patterns
• B) a nitrogenous layer
• C) a greenhouse effect
• D) an ozone layer
• E) reflective clouds

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Definitions:

Bacteria

Microscopic, single-celled organisms that inhabit virtually all environments, including soil, water, organic matter, and the bodies of plants and animals.

Ectopic Pregnancy

A pregnancy in which the fertilized ovum is implanted in any tissue other than the uterine wall. Most ectopic pregnancies occur in the fallopian tubes. Also known as a tubal pregnancy.

Vagina

In females, a flexible, muscular organ that begins between the legs and extends diagonally toward the small of the back. It encompasses the penis during sexual intercourse and is the pathway (birth canal) through which an infant is born.

Unsafe Sexual Practice

Sexual activities that increase the risk of sexually transmitted infections (STIs) and unwanted pregnancies due to the absence of protective measures.