Biology Test 1 Notes 1-3

Chapter 1

Basic Properties of Life

  1. Order → cells, tissues, organs, organ systems

  2. Reproduce

  3. Growth + development (controlled by DNA)

  4. Process energy (chemical)

  5. Respond to stimuli

  6. Regulate internal environment (homeostasis)

  7. Evolutionary adaptation

Organelle

  1. Mitochondria

  2. Lysosomes

  3. Smooth ER

  4. Rough ER

  5. Vacuoles

  6. Golgi apparatus

  7. Ribosomes

  8. Nucleus

Hierarchy of Organization

  1. Biosphere - all environments on Earth where organisms live

  2. Ecosystem - the living organisms within a biosphere & their physical components with which they react

  3. Community - all the living organisms on a particular area

  4. Population - particular species of organism

  5. Organism - any living thing

  6. Organ System - a group of organs performing similar functions

  7. Organ - a group of tissues performing the same function

  8. Tissue - a group of similar cells performing the same function

  9. Cell - the basic unit of life

  10. Organelle - small organs found within the cell with particular functions

Molecule - made up of atoms that are held together by chemical bonds

Types of Cells

Prokaryotic

  • Develops first

  • Smaller of 2 types

  • No membrane bound

  • Nucleus

  • Asexual reproduction

  • Single cell

  • Bacteria

Eukaryotic

  • Membrane bound nucleus

  • Sexual & Asexual reproduction

  • Single and Multicellular

  • Plants, animals, algae

Interaction of Living Organisms with their environment

  1. Producers - make food through photosynthesis

    6Co2+6H2O → C6H12O6+6O2

  2. Consumers - carnivores, herbivores, omnivores

  3. Decomposers

Biotic Factors - living factors (trees, animals)

Abiotic Factors - without life (sand, rocks, water, air)

Dynamics in a Ecosystem

  1. Recycling of Materials

  2. One way energy flow - sunlight is converted into energy by producers → eaten by consumers → exits as heat

Genes - units of heredity that transmit information, genes are grouped in chains

Chromosomes - made up of DNA

DNA → double helix made up of nucleotides

Diversity of Life

Biodiversity

Forest - trees, snakes, deer, rabbit, fungi

Taxonomy - study of classification

Domains

Bacteria - prokaryotes ( most diverse and wide spread) always unicellular

  • Cocci - round

  • Bacillus - elongated

  • Spirillum - corkscrew

Archaea

  • Psychrophiles - found in extreme cold

  • Thermophiles - found in extreme heat

  • Methanogens - produce methane gas (found in the bottom of swamps, ponds, lakes and in our digestive tract)

  • Halophiles - found in extremely salty areas

Eukarya - nucleus that is membrane bound

  • Multicellular (humans)

  • Unicellular (profist, algae)

Evolution - a change over time

Natural Selection - best traits are passed from one generation (survival of the fittest)

Chapter 2 - Chemical Bases of Life

Solids - Liquids - Gases

Element - anything that cannot be broken down into another substance and still retain the properties of the original element

Atomic particles - p+n = atomic mass, p = atomic number

  • Protons(+) - inside nucleus

  • Neutrons(+-) - found in nucleus

  • Electrons(-) - found in orbit outside nucleus

Ions result when you change the number of electrons

Isotopes result when you change the number of neutrons

Different elements are made when you change the number of protons

Valence electrons - one electron found in the outer shell

Noble gases - don’t react with any element because their outer shell is full

Chemical Bonds

How are chemical bonds formed?

  • Covalent bonding - sharing electrons

  • Ionic bonding - atom either gains or loses electrons

  • Hydrogen bonding

Covalent Bonds

  1. Single

  2. Double

  3. Triple

Ionic Bonds

Properties of Water

  1. Strong cohesion (holding together of molecules of one molecule

  2. Adhesion - elements of different kinds

  3. Can form ice (floats because molecules are further apart than water)

  4. Called solvent of life

  5. Moderates temperature

Solvent - substance that does the dissolving

Solute - substance being dissolved

Chemical reaction - changes one substance into another

Ex: 2H2 + O2 ←→ 2H2O

Buffers - substances that minimize change in pH

Acid - substance that has a pH lower than 7

Base (Alkaline) - substance that has a pH greater than 7

Chapter 3 - Molecules of a Cell

Anything that contains carbon is considered organic.

Hydrocarbons - substances that contain hydrogen and carbon

Functional Groups necessary for life

First five are polar and hydrophilic

Hydrophobic - Methyl

  1. Hydroxyl - Hydrogen bonded to O2 ( If bonded to carbon → alcohol)

  2. Carbonyl - Carbon double bonded to O2

  3. Carboxyl - Carbon + Oxygen + Hydroxyl

    black carbon, white hydrogen, red oxygen

  4. Amino - hydrogen, carbon, nitrogen double bonded to hydrogen

    Amino acids are the building blocks of proteins

  5. Phosphate - O2 + Phosphorus

    Energy transfer (DNA, RNA)

  6. Methyl - CH3

Classes of Molecules

Carbohydrates (CHO)

  1. Simple sugars (mono/sacchar/ides) sacchar - sugar

  2. Disaccharides sucrose

  3. Polysaccharide -

    • starches (plant energy)

    • Glycogen - (animal energy)

    • Cellulose - plant cell wall

    • Chitin - exoskeleton of insects, crustaceans

Lipids - don’t dissolve in water

  1. Fats - saturate and unsaturated

  2. Phospholipids - make up the majority of the cell membrane (heads are hydrophilic tails are hydrophobic)

  3. Steroids - natural or artificial (found in cell membrane)

  4. Proteins -

    • Structural amino acids - provide support (hair, connective tissues)

    • Connective tissues muscles

    • Transport - hemoglobin (loves oxygen, carbon-monoxide)

    • Signaling devices (insulin)

    • Catalyst - regulate body functions

    • Immunological - used in defense of foreign objects

    • Nucleic acids - DNA RNA