Unit 1 Welcome to Biology!

Essential Questions 1. What is science? 2. What is an organism and how is it related to biology? 3. What characteristics do all living things share? 4. Why do you need to know chemistry to study biology? 5. What are the 4 substances all organisms are made of and what are they used for? 1. What is science? 2. What is an organism and how is it related to biology? 3. What characteristics do all living things share? 4. Why do you need to know chemistry to study biology? 5. What are the 4 substances all organisms are made of and what are they used for?

What is Science? Science is a way of studying something and making rules about it. What is Biology? Biology is the study of living things Examples: humans, animals, plants, bacteria, insects, fungus

Scale of Life Biosphere –All parts of the Earth where there is life Ecosystems –Community of living things in an area, along with nonliving things Organisms –An individual living thing –Species: distinct form of life Cells: –life’s basic unit of structure and function DNA –Chemical responsible for inheritance Biosphere –All parts of the Earth where there is life Ecosystems –Community of living things in an area, along with nonliving things Organisms –An individual living thing –Species: distinct form of life Cells: –life’s basic unit of structure and function DNA –Chemical responsible for inheritance

3 Domains of Life Archea Bacteria Eukarya –Animalia –Plantae –Protista –Fungi Archea Bacteria Eukarya –Animalia –Plantae –Protista –Fungi

Characteristics of Life All Living Things…

…Require Energy Need energy to carry out activities, like metabolism and movement Usually ATP Need energy to carry out activities, like metabolism and movement Usually ATP

… Try to keep a balance Homeostasis: Maintain internal balance Ex. sweating Homeostasis: Maintain internal balance Ex. sweating

…Reproduce Reproduce either sexually or asexually

… Pass Information to Offspring Inherit traits from parents

…Are Made of Cells Cells are the basic components of all living things Single-celled or multi- cellular Cells are the basic components of all living things Single-celled or multi- cellular

… Respond to Stimuli Respond to stimuli in their environment

… Adapt and Evolve Adapt to particular environments and evolve over time

2-2 Basic Chemistry Most of the processes in life are chemical All organisms are made of the same basic building blocks The world is made of many different substances –Hundreds of thousands are known –All are made up of atoms combined in different ways Most of the processes in life are chemical All organisms are made of the same basic building blocks The world is made of many different substances –Hundreds of thousands are known –All are made up of atoms combined in different ways

Atoms atom: smallest possible particle of an element –cannot be broken down by chemical means Subatomic particles – proton: single unit of positive electrical charge (+) – electron: negative electrical charge (-) – neutron: electrically neutral = no charge An element’s physical and chemical properties depend on the number and arrangement of its subatomic particles –Ex. Shiny luster of copper metal atom: smallest possible particle of an element –cannot be broken down by chemical means Subatomic particles – proton: single unit of positive electrical charge (+) – electron: negative electrical charge (-) – neutron: electrically neutral = no charge An element’s physical and chemical properties depend on the number and arrangement of its subatomic particles –Ex. Shiny luster of copper metal

Elements Matter: anything that occupies space and has mass Element: pure substance that cannot be broken down into other substances by chemical means –Ex. gold(Al), carbon(C), oxygen(O) –25 essential to life 96% of our body is made of: oxygen, nitrogen, carbon, hydrogen Compound: 2 or more elements –Ex. Carbon dioxide(CO 2 ), water(H 2 O) Matter: anything that occupies space and has mass Element: pure substance that cannot be broken down into other substances by chemical means –Ex. gold(Al), carbon(C), oxygen(O) –25 essential to life 96% of our body is made of: oxygen, nitrogen, carbon, hydrogen Compound: 2 or more elements –Ex. Carbon dioxide(CO 2 ), water(H 2 O)

Chemical Bonds the force holding 2 atoms together –Ionic Bonds –Covalent Bonds molecule: group of atoms that form the smallest unit of a substance that can retain its chemical properties the force holding 2 atoms together –Ionic Bonds –Covalent Bonds molecule: group of atoms that form the smallest unit of a substance that can retain its chemical properties

Ionic Bonds ionic bond: an atom transfers an electron to another atom – ex. NaCl ion: atoms that have become electrically charged as a result of gaining or losing electrons ionic bond: an atom transfers an electron to another atom – ex. NaCl ion: atoms that have become electrically charged as a result of gaining or losing electrons

Covalent Bonds covalent bonds: two atoms share electrons –Number of bonds formed= additional in highest level covalent bonds: two atoms share electrons –Number of bonds formed= additional in highest level

2-3 Macromolecules macromolecule: large molecules that are made up of small molecules All organisms are made of 4 major types –Carbohydrates –Lipids –Proteins –Nucleic Acids organic molecule: contain carbon macromolecule: large molecules that are made up of small molecules All organisms are made of 4 major types –Carbohydrates –Lipids –Proteins –Nucleic Acids organic molecule: contain carbon

Carbohydrates carbohydrate: organic compound made up of sugar molecules Sugars contain carbon, hydrogen and oxygen –Ratio 1C:2H:1O –Glucose= C 6 H 12 O 6 carbohydrate: organic compound made up of sugar molecules Sugars contain carbon, hydrogen and oxygen –Ratio 1C:2H:1O –Glucose= C 6 H 12 O 6

Simple Carbohydrates Sugars –Glucose, fructose, sucrose –Excess glucose is converted to fat for storage –Candy, fruit sugar Sugars –Glucose, fructose, sucrose –Excess glucose is converted to fat for storage –Candy, fruit sugar

Complex Carbohydrates Simple carbohydrates linked together to form long chains Starches: wheat, rice, corn, potatoes Glycogen: stored form of glucose in muscles and liver of animals Cellulose: support in plants; “fiber” Simple carbohydrates linked together to form long chains Starches: wheat, rice, corn, potatoes Glycogen: stored form of glucose in muscles and liver of animals Cellulose: support in plants; “fiber”

Lipids lipids: class of compounds that is hydrophobic (water- fearing) Fats and oils –Protect organs, insulation, prevent skin from drying out, act as a boundary that surrounds and contains the aqueous contents of your cells –Twice the energy of carbs Waxes –Waterproofing (leaves) Steroids –Cholesterol, estrogen, testosterone lipids: class of compounds that is hydrophobic (water- fearing) Fats and oils –Protect organs, insulation, prevent skin from drying out, act as a boundary that surrounds and contains the aqueous contents of your cells –Twice the energy of carbs Waxes –Waterproofing (leaves) Steroids –Cholesterol, estrogen, testosterone

Proteins protein: a polymer constructed from a set of just 20 kinds of monomers called amino acids. –responsible for almost all of an organism’s functioning –Muscles, hair, structural parts of cells, cartilage and bone, enzymes, hormones protein: a polymer constructed from a set of just 20 kinds of monomers called amino acids. –responsible for almost all of an organism’s functioning –Muscles, hair, structural parts of cells, cartilage and bone, enzymes, hormones

Nucleic Acids DNA: dexoyribonucleic acid RNA: ribonucleic acid Carry genetic info DNA makes up chromosomes DNA: dexoyribonucleic acid RNA: ribonucleic acid Carry genetic info DNA makes up chromosomes