Science Section 1 Flashcards
What is Environmental Science?
The study of the impacts of human activities on environmental systems
what is an environment?
the sum total of all the conditions and living and nonliving factors that surround an organism
What is an environmental indicator?
a measure that reflects the environmental health of a system.
What are the six main environmental indicators of the Earth’s health?
1 Biological diversity
2 Human population growth
3 Food Production
4 Resource consumption
5 Global temperature and atmospheric greenhouse gas levels
6 Pollution levels
What is biological diversity? (in terms of the whole planet)
diversity of genes, species, habitats, and ecosystems on Earth
What is a species?
a group of organisms that is distinct from other groups in morphology (body type), physiology, or biochemical properties. Individuals within a species can breed and produce viable offspring.
How many known species are there on Earth?
approximately 1.8 million
How many species likely exist on Earth in total?
ten times as many as are currently discovered
What percent of species that were once present on Earth are now extinct?
99.9%
What is the normal background extinction rate?
two mammal extinctions per 10,000 species per one hundred years
What is the current extinction rate (mostly due to human activity)
as many as 40,000 species per year may be going extinct
What types of species have a much greater impact on their ecosystem than their population size would suggest?
keystone species
What can extinction of keystone species cause?
a cascade of extinctions of species dependant on them
When did the Earth’s global population reach 8 billion people?
November 2022
How many people are born and die every day?
Roughly
378,000 infants born
148,000 people die
230,000 new inhabitants on Earth each day, or almost a million new people on Earth every four days
