AH

Biology Ch. 1 X

  • Biology is the study of life. It unifies much of natural science.

  • Life is constrained by the properties of chemistry and physics

  • science is becoming more interdisciplinary

  • Characteristics of all Living things

    1. Cellular Organization (prokaryote and eukaryote)
    2. Ordered Complexity (metabolic pathways)
    3. Sensitivity to Environment (react/adapt)
    4. Growth, Development, and Reproduction (fission)
    5. Energy Utilization (reactions in a cell- exergonic)
    6. Homeostasis (physiological responses that regulate normal conditions)
    7. Evolutionary Adaptation (change overtime)

  • Hierarchical organization of living systems

    • cellular level is the smallest
    • cell-tissue-organ-organ system-organism-population-community -ecosystem-biosphere
    • Population: particular species in a particular place
    • Community: interacting population
    • Ecosystem: community plus physical environment
    • Biosphere: all ecosystems together (Earth)Biosphere: all ecosystems together (Earth)

  • Nature of Science

    • aims to understand the world through observation and reasoning.
    • As Specific as possible
    • Inductive Reasoning: from specific ideas to general ideas

    ex: establishing a cell theory

    • Deductive Reasoning: from general to specific ideas

  • Independent Variable: the one that we change

  • Dependent Variable: result or what you measure

  • Scientific Theory- elevating conclusions to a level of theory

  • Evolution Theory: common ancestor an adapted

  • Biogenesis Theory: life only comes from life

  • Gene Theory: organisms have coded info that determine form, function and to some extent behavior

  • Darwin was not the first to propose evolution

  • Darwins contribution was a mechanism

  • Natural selection: is a mechanism for evolution; variation of a feature, certain versions are advantageous; it is heritable

  • We must have energy to exist

  • humans- food- sun- photosyntesis

  • Genome: entire set of DNA instructions

  • Gene: particular segment of DNA or discrete unit of inheritance

  • CENTRAL DOGMA

  • Reductionism: the general approach of biochemistry

  • Basic Research: teachers etc

  • Applied Research: research used from those teachers

Chapter 2

  • Atoms are composed of protons neutrons and electrons
  • APE MAN (Atomic Number, Element, Atomic Mass)
    • Electrons: negatively charged particles located in orbitals
    • Neutral atoms have the same number of electrons and protons
  • Ions: charged particle electrons change
  • Atomic Number: equal to the number of protons
  • Element: canā€™t be broken down into another substance by ordinary means
  • Atomic Mass: sum of protons and neutrons
  • Cations (cat eyes)
  • Anion (ant)
  • Isotopes: atoms of a single element that possess different numbers of neutrons
  • Radioactive isotopes are unstable
  • Nucleus is center of an atom ( DNA inside nucleus)

Electron Arrangement

  • energy levels

    KLM (k is inner) K-2 L-8 M-8

  • If an atom has a full outer shell it is non reactive

Redox

  • LEO says GER

Oxidation: lose electron

Reduction: gain electron

  • valence electrons: outer most shell
  • Inert: atoms outer most level is full
  • Octet rule: must have 8

CHON

  • carbon hydrogen oxygen nitrogen make up 96.3 % of body
  • Molecule: group of 2 or more atoms held together in a stable association
  • Compounds: molecule containing more than one element

all compounds are molecules but not all molecules are compounds

Bonds

  • Ionic bonds: formed by the attraction of oppositely charged ions
  • Loses an electron to have a positive charge
  • Gains an electron to have a negative charge

electrical attraction of water molecules can disrupt forces holding ions together

  • Covalent Bonds: form when atoms share 2 or more valence electrons
  • Strength of a covalent bond depends on number of bonds present

Electronegativity