Biology- “Study of Life”
Science - “to know”
The characteristics of life below is an overview for the year, they all are at least 1 or more chapters in the book
5 Main Characteristics of Life- (book has more)
1. Made of cells
3. Obtain and use energy- (eating/digest/excrete)
4. Grow and develop/repair- (goes along with #3)
5. Respond to environment/stimuli
1. Made of cells- smallest unit of life.
A. Single Celled- one cell- Paramecium- largest living single celled animal, Ostrich egg is largest single cell.
Ostrich egg = 25 chicken eggs by volume.
B. Multi-cellular- many cells.
2. Reproduce- making of new organisms (cells)
A. Asexual- (MITOSIS) 1 parent cell- 2 daughter cells, genetically identical. *** all cells except sperm/egg***
B. Sexual- (MEIOSIS) 2 cells combine to make 1 offspring genetically different- ½ # of chromosomes of original cell.
3. Grow and develop/repair
Metabolism- sum of all chemical reactions in an organism
All source of energy for life is SUN!
Anabolism- (PHOTOSYNTHESIS) small to big- making food- plants
Catabolism- (CELLULAR RESPIRATION)- ex. digestion, LARGE to SMALL- think catastrophe. (Big LARGE building, crumbles to SMALL rubble).
4. Obtain and use energy- “get food and use it to grow and repair”
5. Respond to the environment/stimuli-
Homeostasis- “same condition”- balance of body systems with environment.
Constant body temperature
The biological goal of organisms is to reproduce. Once “you” have passed your genes to future generations, this is your biological goal.
Genes- basic unit of heredity
Heredity- passing of traits to offspring. Study of this is called Genetics.
A change in the genetic code is called mutation
Mutation- change in code, can be harmful or helpful, most are NOT harmful. If organism is “better or more fit to survive”, then this is called evolution.
Evolution- change in a species over generations. Species- organisms that can reproduce and produce offspring- “kids” that can reproduce.
If an organism adapts- this “Survival of the Fittest” If the traits are selected naturally based on being “better” = Natural Selection.
Populations- Organisms/species that live together within an ecosystem.
Ecosystems- Area of Earth chemically and biologically connected.
The living Earth is called the Biosphere.