Biology—The Science of Life

Old Growth Forest

Vocabulary List for Chapter One

• Adaptation Development• Biology Energy• Cellular respiration Evolution• Chlorophyll Food Chain• Community Growth• Consumer Homeostasis• Decomposer Organism• Photosynthesis Producer• Reproduction

Biology• Bios is the Greek word for

life or way of life.• Biology is the study of life.• All life as we know it can be

found in the biosphere, which is the thin envelope of space surrounding Earth (about 12 miles) and projecting a short distance below Earth’s surface.

Biosphere

What distinguishes living things?• Living things reproduce

resulting in offspring.• Young organisms grow

and develop.– Growth is an increase in

the amount of living material in an organism.

– Development is the series of changes an organism undergoes in reaching its final, adult form. Life cycle of a butterfly

Living things continued• Living organisms maintain

homeostasis, the steady state of the internal operation of an organism regardless of external changes.

• When you get too hot, your body gets rid of the excess heat by perspiring.

• Because external factors change constantly, it’s imperative that organisms maintain homeostasis.

Living things continued (again)• Each function or life process

that an organism performs is vital to its existence. None is isolated from the others—they all come together and interact with each other to create a single, orderly living system. This precise organization is characteristic to all life forms.

Diatoms in Schuylkill water source in Pennsylvania

Organisms and Community

• While an organism is anything capable of carrying out life processes, a community is an assortment of life forms within a given place where all the organisms react and depend upon one another in a symbiotic relationship.

These fish eat parasites off of the shark and in return receive protection from other predators in a symbiotic relationship.

Food and Energy• Energy is the ability to do work.• Food provides energy.• Producers are members of the

community that make the food.• Most producers make food

using carbon dioxide (CO2) and water (H2 O) .

• Chlorophyll, found in plants, traps light from the sun and produces oxygen and glucose in this chemical reaction:

• 6CO2 + 6H2 O C6H12O6 + 6O2

Carbon cycle and photosynthesis

Consuming Food• Producers make food for

themselves and serve as food sources for other members of the community.

• Organisms that cannot make their own food are called consumers.

• Producers and consumers convert the energy in glucose through cellular respiration.

Cellular respiration

Food Chains

• Food and thus energy is passed from producers through a series of consumers. This passage is called the food chain.

• Different sets of organisms create different food chains.

Food chain

Decomposers

• Decomposers feed on the dead remains and waste products of living organisms.

• If it weren’t for the decomposers, nothing would decay and our environment would indeed be less than desirable! Decomposers