SCS 7th Grade Science-Section 1 What is Life?

organisms

Any living thing

cell

The smallest/basic unit of structure and function within an organism.

microscope

A tool that uses lenses to magnify small objects

Unicellular

uni" means one or single.
A single-celled organism
Example- bacteria

Multicellular

Multi" means many.
Organisms composed of many different cells.
Example - A human body

water

The most abundant chemical in cells

carbohydrates

A cell's main source of energy

proteins and lipids

The building materials of cells

nucleic acids

Genetic material that gives chemical instructions about how each cell should function.

stimulus (stimuli)

A change in an organism's surroundings that cause it to react. Something that causes a cell to react
Example- loud noise, light, explosion, roller coasters.

response

An action or change in behavior based on a stimulus. Example- You experience fear and scream when someone jumps out at you.

development

The process of change that occurs during an organism's life to produce a more complex organism.

reproduction

The ability to produce offspring that are similar to the parents

spontaneous generation

The incorrect idea that living things can be produced from nonliving sources.

controlled experiment

an experiment in which a scientist carries out tests changing only one variable at a time

autotroph

auto"-means self "troph"-means feeder
organisms that make their own food in orderto cary out their cell's functions. Example- plants

heterotroph

hetero" -means other "troph"- means feeder
organisms that get their energy from eating food produced by other sources. Example humans and animals.

living space

a place/space where an organism gets food water and shelter in order to survive.

homeostasis

maintaining or keeping a stable internal condition within a cell so that it can survive and be healthy

Louis Pasteur

Scientist of the 1800's that proved that proved spontaneous generation was false. He experimented with mold growing on beef broth.

Francesco Redi

Scientist of the 1600's that proved spontaneous generation was false. He experimented with maggots growing on raw meat.