1.3: Studying LIFE VOCABULARY: –Biology –DNA –Stimulus –Sexual reproduction –Asexual reproduction –Metabolism –Homeostasis –Biosphere –Evolve

What are some characteristics of living things? What does it mean to be “ALIVE”? 1) Living things are ORGANIZED.

Made up of cells –UNICELLULAR: one celled –MULTICELLULAR: many celled

2) Living things are based on a universal genetic code:

● ASEXUAL = one parent; cell division, cloning, budding, regeneration 3) Living things REPRODUCE.

● SEXUAL = two parents; sperm and egg 3) Living things REPRODUCE.

Growth: increase in size & formation of new structures (could be at the cellular level) Development: cells increase in number and become different (differentiate)

Heat Light Pressure Sound Gravity Examples: A plant seed only germinates when there is sufficient water and temperature. Plant roots grow down. Plant leaves grow towards sunlight.

HOMEOSTASIS: process by which organisms keep their internal conditions relatively stable –Example: How do humans maintain the same body temperature? too hot… we sweat too cold… we shiver

7) Living things require ENERGY. All living things use energy: make their own energy or consume energy –PHOTOSYNTHESIS: using light energy to make “food” energy –METABOLISM: combination of chemical reactions through which an organism builds up or breaks down materials Photosynthesis Uses Metabolism

8) ADAPTATION & EVOLUTION ● ADAPTATION: any structure, behavior, or internal process that enables an organism to respond to stimuli and to better survive in a particular environment

8) ADAPTATION & EVOLUTION ● EVOLUTION: change over time –A group of organisms can change over time –Even though an individual develops, their inherited traits do not change leg bone in a whale

Branches of Biology Diversity of life is so great, biology is separated into branches –ZOOLOGY: study animals –MICROBIOLOGY: study bacteria –BOTANY: study plants –ETHOLOGY: study animal behavior –PALEONTOLOGY: study life from the past

Biosphere > Ecosystem > Community > Population > Organism > Organ Systems > Organs > Group of Cells (Tissues) > Cells > Molecules > Atoms > Protons, Neutrons, Electrons

How do we study living organisms? Key Concepts: –What measurement system do most scientists use? –How are light microscopes and electron microscopes similar? How are they different? Vocabulary: –Metric system –Microscope –Compound light microscope –Electron microscope –Cell culture –Cell fractionation

Metric System Length: –Meters Mass: –Grams Volume: –Liters Temperature: –ºCelsius

kilohectodeka(g, m, or L) decicentimilli SCALE = multiples of 10

Analyzing Biological Data The simple way to record data ● Make a table… ● Then make a graph –Graphs make patterns easier to recognize and understand

GRAPH = visual representation of data 1) DESCRIPTIVE title 2) x and y axis labeled 3) units for both the x and y axis 4) scale is evenly and correctly spaced for data 5) legend / key when appropriate Organizing Data Data is organized and presented in tables, charts, and graphs.

LINE GRAPH: best for displaying data that CHANGE. –Independent Variable: x-axis –Dependent Variable: y-axis

BAR GRAPH: useful when you want to compare data for several individual items

MICROSCOPES! Light Microscopes Electron Microscopes

MICROSCOPES COMPOUND LIGHT MICROSCOPE: most common scope Advantages: get higher magnification than with a dissecting scope. Drawbacks: the light comes from below so sample must be very thin so you can see –Useful for viewing single cells –Usually view dead things with this microscope. Limit of resolution: if you magnify beyond this point, the object will be blurry.

EYEPIECE LOW-POWER OBJECTIVE HIGH-POWER OBJECTIVE STAGE STAGE CLIPS BASE MIRROR LAMP IRIS DIAPHRAGM COURSE ADJUSTMENT FINE ADJUSTMENT ARM COURSE ADJUSTMENT FINE ADJUSTMENT ARM

DISSECTING MICROSCOPE: used to view dissection or small live (sleeping) animals such as fruit flies. Advantages: can view samples that are alive; large field of view Drawbacks: magnification is not as high as other microscopes.

SCANNING ELECTRON MICROSCOPE (SEM): used to see very small “stuff” Advantages: can study very small objects such as viruses and individual molecules; limit of resolution is 1000x that of a light microscope. Drawbacks: done in a vacuum, so object must be dead; also very expensive!

PINHEAD Face of an ant!

Laboratory Techniques ● Cell Culture: -a group of cells develops from a single original cell. ● Cell fractionation & Centrifugation: -used to separate the different parts of a cell 1) Cells are blended 2) Added to a liquid and placed in a tube 3) Centrifuge at 20,000 revolutions per minute 4) Spinning separates the cell parts by density.

In comparing differences in sea level from decade to decade, a scientist should use what type of graph? a)Bar graph b)Pie Chart c)Line graph

On that graph, what would be on the x-axis? On the y-axis? X-axis = time in decades Y-axis = sea level in kilometers

Welcome to BIOLOGY! BIOLOGY!