biology midterm

biology

biology

the study of life

scientific method

1.) Make observations

2.) Ask questions

3.) Perform research

4.) Create hypothesis

5.) Test your hypothesis (by conducting an experiment)

6.) Analyze results and draw conclusion

7.) Present findings

quantitative data

• numbers (quantity)

• Easily measured

qualitative reasoning

• observation that can not be measured, for ex.) texture, color, shape, etc. (quality)

• Not easily measured

SI units/metric system

Length = meters (m)

Volume = liters (L)

Mass = grams (g)

Time = seconds (s)

Temperature = degrees Celsius (℃)

metric system vs. English system

The metric system operates in units of 10, making it more precise and more accurate

metric conversions - both ways

Kilo/ K

I

Hecto/h

I

Deca/ da

I

Base Unit

m/g/L

I

Deci/d

I

Centi/c

I

Milli/m

Examples)

1.) 15.8 dm = 0.158 dam

2.) 5.67 mL = 0.00567 L

3.) 1,862 hg = 1,862,000 dg

observation vs. inference

Observation = use senses to gather

• Info gathered = data

Inference = created from your data and observations based on what you see

hypothesis

possible explanation for observations gathered and tested through a controlled experiment

• If..., then

controlled experiment

• How we test our hypothesis

• Only change one variable

control vs. experimental group

Control group - exposed to all of the same conditions except for the independent variable

• "Normal" conditions

• "Placebo"

• ex.) plant exposed to sunlight

Experimental group - being observed and changes in response to the independent variable

• ex.) groups exposed to different colored lights

independent variable

• what is changed/ manipulated

• being tested

• ex.) light color on flowers

dependent variable

• what changes in response to the independent variable

• what is measured

• usually last sentence of description

• ex.) plant height

variables vs. constants

Variables - any characteristics that can take on different values, such as height, age, temperature, or test scores

Controlled - only change one variable

Constant - a variable that remains the same across all groups

conclusion

summary of results saying what they found that they then share to the rest of the science community

Graphing Data/ Placement of independent and dependent variables on graph

Independent variable - x axis

Dependent variable - y axis

Microscope Types

Compound light microscope (what we use) - can see bother living and non-living things

• requires a stain

Electron Microscopes - only can observe non-living things

Transmission electron microscope - can see internal structure of a cell

Scanning electron microscope - produces 3D images

homeostasis

• maintaining stable internal conditions

• ex.) sweating, shivering

evolution/adaptation

• occur over multiple generations

• ex.) Darwin's finches/ rattlesnakes and feral hogs

metabolism

the chemical reactions in the body's cells that change food into energy

Characteristics of all living things

1.) Cells

2.) Maintain homeostasis

3.) Adapt or evolve over time

4.) Reproduction

5.) Growth and development

6.) Genetic material

7.) Require energy

8.) Respond to stimuli

9.) Organization

Levels of organization in biology

1.) Atom

2.) Molecule

3.) Organelles

4.) Cells

5.) Tissues

6.) Organ

7.) Organ system

8.) Organism

Parts and charge of an atom

• Protons = positive charge (+)/ located in the nucleus

• Neutrons = neutral (no charge)/ located in the nucleus

• Electrons = negative charge (-)/ located on the outer orbits

Determine the number of p,n.e of a neutral atom or an ion

• Equal number of protons and electrons

• the number of neutrons does not matter