Biology = the Study of Life

Studying Life Chapter 1.3

Biology = The Study Of Life

Characteristics of Life • Every living thing, although different, shares the same 8 characteristics – ______– Obtains and uses ______– Responds to stimuli / Adapts to the environment – ______– Grows and develops – Has the same universal ______– Maintain an internal steady environment- called______– As a group, living things change over time

Has Cells • Cell – The ______living part of an organism • Organism can consist of 1 cell or ______of cells • Cells carry out specific functions that allow organism to survive

Obtains and Uses Energy • All organisms must have ______to live • Ultimate source of energy is the ______• Organisms either use the sun or other organisms for energy • ______– The sum of all the chemical reactions which an organism carries out for its life processes

Responds to Stimuli /Adapts to the Environment • Stimulus – Any change in the environment that causes a ______• Response – The reaction of an organism to a ______

Reproduces • Ability to create new offspring and continue the species – ______reproduction • New organism has one parent – ______reproduction • New organism has two parents – ______• The ability to reproduce • Only characteristic that is necessary for the continuation of life Growth and Development • Growth – Increase in ______of an organism • Development – Change or ______of an organism

Universal Genetic Code • DNA – ______– Contains the directions for inheritance of traits

Maintains Internal Environment • Homeostasis – Maintenance of an ______, despite what is happening in the external environment • Works like a thermostat in a house

Evolution • Change over time • Individual organisms cannot evolve, but groups of organisms can

Levels of Organization

Biosphere The part of Earth that contains all ecosystems Biosphere

Ecosystem Community and its nonliving surroundings

Hawk, snake, bison, prairie dog, grass, stream, rocks, air Community Populations that live together in a defined area

Hawk, snake, bison, prairie dog, grass Population Group of organisms of one type that live in the same area Bison herd

Individual Organism living thing

Groups of Tissues, organs, Cells and organ systems Brain Nervous tissue Nervous system Smallest Cells functional unit of life Nerve cell

Groups of Molecules atoms; smallest unit of most chemical compounds Water DNA

Chapter 1.4: Tools and Procedures

The Metric System • Most scientists use the metric system when collecting data and performing experiments – Also called the SI system

àWhy – decimal system of measurement scaled on the multiples of ______– easy to use – everyone else uses the metric system

Measurements in the Metric System • Length is measured in à

• Mass is measured in à

• Volume is measured in à______if liquid or à ______if solid

• Temperature is measured in degrees à

The Microscope • Any device that produces ______images of structures that are too small to see with the unaided eye

The Light Microscope vs. The Electron Microscope • Light Microscopes àfocuses ______rays to magnify image àcan magnify up to ______

Example: The Compound Light Microscope • Uses ___ lenses and allows light to pass through specimen • Can study ______organisms, no smaller than 2um. • Uses ______to make images easier to see and 3D

• Electron Microscopes àfocuses beams of ______to magnify image àproduces images ______greater than C.L.M. àcan’t observe ______specimen àslides must be in a vacuum

Examples:  Scanning Electron Microscope (SEM) • Electrons travel across the ______

 Transmission Electron Microscope (TEM) • Electrons travel ______a thin sample of a specimen

Review Questions

• Name an organism and give an example of how they demonstrate 5 of the 8 characteristics of life – 1. – 2. – 3. – 4. – 5.

• Using a Venn Diagram, show the differences and similarities between a compound microscope and an electron microscope.