1.1 What is Biology? Pages 3-10

Biology- Greek Word Bios- life Logos- study Means study of life Learning about living organisms around you

Biologists study interactions among living things No man is an island We live with other organisms, Ex. E. coli in your intestines help digest your food Depend on other organisms for living Ex. Plants give us wheat to eat & Oxygen to breath

Characteristics of Life

Characteristics of Living Things Organisms- possess all the characteristics of life Five characteristics

Which are organisms?

1. Living things are organized All living things have cells Cells- building blocks of living organisms Small organisms have one cell (unicellular)

Multicellular can exist on tissue, organ, or organ system level sponge worm Big organisms build cells and form tissues, which form organs, which form organ systems (Multicellular) Multicellular can exist on tissue, organ, or organ system level

                                          

2. Living things can reproduce Reproduction- production of offspring A species can’t continue if they do not replace themselves Species- group of organisms that can breed and produce fertile offspring Ex. Humans are Homo sapiens 4th-whole slide

Types of Reproduction Two Types Sexual Reproduction- two cells from different parents unite to produce the first cell of a new organism Asexual Reproduction- new organism has a single parent Usually organism divides in half to form 2 new organisms Or a portion of an organism splits to form new organism

Which type of Reproduction?                                                           1 2

Living things are based on a genetic code Asexual reproduction results in offspring and parent having identical traits (1 parent) Sexual Reproduction results in traits varying from parent and offspring (2 parents) Directions for inheritance are based on DNA (genetic code)

3. Living things change during their life Growth- increase in the amount of cells and formation of structures (size) The smaller the organism, the less changes Development- changes in an organism’s lifetime (structure or function)

4. Organisms adjust to their environment Ex. Sarah is hot, so she turns on the A/C She responded to a stimulus Stimulus- causes an organism to adjust to its environment Response- reaction to the stimulus 2nd-whole slide

Organisms maintain a constant internal environment called homeostasis Ex. Body temperature 98.6°F

Organisms maintain homeostasis with energy Energy- obtained by food, unit is the Calorie Organism do work to obtain this food Plants make their own, animals consume plants or other animals

5. Living things adapt and change over time Adaptation- organism changing to better survive in their environment Adaptations are inherited from parents

Mimicry monarch Viceroy

Evolution-simply “change over time” Adaptation over long periods of time(thousands to millions) of years is called evolution Evolution-simply “change over time” A VERY long time!!!