What Is Life? Chapter 1
Characteristics of Living ThingsLife Comes From Life
Needs of Living ThingsLiving, Non-living & Dead
Characteristics of Living Things: All living things… Are made of
cells. Have the Ch
emicals of Life.
Use Energy. Are able to g
row and develop.
Will respond to a stimulus.
Are able to reproduce.
Cellular Organization Cells: The basic unit of
structure and function in an organism.
Organism: A living thing that shares all of the characteristics of living things.
Unicellular: single celled organisms (bacteria)
Multicellular: Many celled organisms
Chemicals of Life Water (most abundant) Carbohydrates (energy
source) Proteins & Lipids
(building materials) Nucleic Acids (genetic
material)
Carbohydrates: The main source of
energy for living things. Sugar and starch Fruits
Proteins: Eggs, meat, fish, beans,
nuts and poultry. Made up of Amino Acids. Needed for the growth
and repair of body structures.
Hair and muscles. Provide energy.
Nucleic Acids: The blue prints of organic
chemicals. Large compounds. Help to make proteins. DNA and RNA are Nucleic
Acids.
Energy Use: Metabolism: The chemical
reactions performed by a living organism. Needed for growth, to store energy, and repair cells.
Ingestion: How a living thing takes in or produces food.
Digestion: The process of breaking down food into simpler substances.
Energy continued: Respiration: The process
of a living thing taking in food to produce energy.
Excretion: The removal of waste products.
Response:
Stimulus, (Stimuli: plural): The signals to which an organism reacts.
Response: The action or movement or change caused by a stimulus.
Growth & Development Growth: the process of
becoming larger. Development: the
process of change that occurs during an organism’s life to produce a more complex organism.
Reproduction:
Sexual Reproduction: requires two parents. Most multicellular organisms reproduce this way.
Asexual Reproduction: reproduce with only one parent. Bacteria, yeast and some plants reproduce this way.
Changing an old theory: Spontaneous Generation:
Before the 1600’s people believed that life could spring from non-living things.
Francesco Redi: an Italian doctor in 1668 helped to disprove Spontaneous Generation.
Louis Pasteur Mid-1800’s French Chemist Proved that Spontaneous
Generation was not true. He compared bacterial
growth in boiled and un-boiled broth.
Pasteurization
Needs of Living Things:
Food Water Living Space Stable Internal Conditions
Food Autotroph: a kind of living
thing that can make it’s own food. Auto means “self” and troph means “feeder”.
Heterotrophs: a kind of living thing that cannot make their own food. Hetero means “other”. They must obtain energy by feeding on others.
Stable Internal Conditions Homeostasis: To maintain
a stable internal condition. Organisms must be able to keep the conditions inside their bodies stable, even when conditions in the surroundings change.
Living Things: Have all 6 characteristics
of living things or have the potential to (seeds).
Cells Chemicals of Life Use Energy Respond to their
surroundings Grow and Develop Reproduce
Non-living Things: Do not have all of the 6
Characteristics of living things. It may have some, but not all!
It may never have been alive (rock), OR
It may have been alive once (tree), but went through a chemical or physical process and was changed (chair).
Dead: It once was alive, but no
longer is. It may still have cells or
chemicals of life, but they no longer function.
The End
Created by Mrs. Scibelli
Science Explorer From Bacteria to Plants