Living Things and the Environment SECTION 1-1

Objectives What does an organism get from its environment? What are the two parts of an Organism’s habitat? How is an Ecosystem organized?

What is biology? The study of life. What do biologists do? Biologists fall into many categories: Macro-biologists: study multicellular organisms Microbiologists: study single-celled organisms Biochemists: study chemistry of living things Naturalists: study/describe nature Field Biologists: collect data “in the wild” Laboratory Biologists: perform lab experiments Doctors/Health Care Professionals

Do you think like a biologist? Hawaiian Green Sea Turtle (threatened species) Turtles and Human Beach-goers This is the turtle’s habitat; I am the visitor here. What would this turtle be doing if I were not here? How does this turtle fit in the local food web?

What is ecology? The study of how living things interact with each other and with their environment is called ecology.

Mexican prairie dog (Cynomys mexicanus)

Native to Mexico, diurnal, herbivorous, social rodent

Endangered due to agricultural practices (treated as a pest, habitat use by humans)

Which living and nonliving factors can you identify?

Nonliving Factors: Abiotic

Abiotic Factor The nonliving parts of an ecosystem are called abiotic factors.

Biotic Factors The living parts of an ecosystem are called biotic factors.

Biotic Factors An organism interacts with both the living and nonliving things in its environment.

Abiotic and biotic factors are the two parts of an organism’s habitat.

What does an organism get from its environment? All the living and nonliving things that interact in a particular area make up an ecosystem.

Ecologists, scientists who study ecology, look at how all the biotic and abiotic factors in an ecosystem are related.

Ecologists study how organisms react to changes in their environment.

How is an Ecosystem organized? Organisms Populations Community Ecosystem

Organisms A species is a group of organisms that are physically similar and can reproduce with each other to produce fertile offspring.

Populations All the members of one species in a particular area are referred to as a population.

Community All the different populations that live together in an area make up a community.

The smallest unit of organization is a single organism, which belongs to a population of other members of its species.

The population belongs to a community of different species.

Ecosystem The community and abiotic factors together form an ecosystem.

Living things constantly interact with their surroundings, responding to changes in the conditions around them.

Review

How was the prairie dog ecosystem organized? Ecological Organization The smallest level of organization is the organism. The largest is the entire ecosystem.

Living Things and the Environment Biotic and Abiotic Factors Salt is an abiotic factor found in some environments. To see how the amount of salt affects the hatching of brine shrimp eggs, varying amounts of salt were added to four different 500-mL beakers.

Living Things and the Environment Factors in a Prairie Habitat A prairie dog interacts with many biotic and abiotic factors in the prairie habitat.