Unit 1 Biology packet: Biology Basics

What is a fact?

an objective, verifiable observation (example: water boils at 100C)

What is a principle?

a statement based on repeated experimental observation that describes an aspect of the world (example: greenhouse effect)

What is a law?

a broad concept or principle that describes patterns in nature and are often accepted as facts (example: Newton’s laws of motion)

What is a theory?

an explanation of an observed phenomenon and organizes facts and research from scientists to explain why but never becomes a fact or law (example: evolutionary theory)

What is science based on?

experimentation

What is the best glassware for measuring?

graduated cylinders

What is the curved line on a graduated cylinder called?

meniscus

What is the best glassware for performing small chemical reactions?

test tubes

What are used for growing bacteria cultures?

Petri dishes

What are the steps to an investigative process sequence?

1. ask a question

2. conduct background research

3. construct a hypothesis

4. test the hypothesis in an experiment

5. analyze the data

6. draw conclusions and communicate them

What is an observation?

a description of something you can see, smell, tough, taste, or hear and is not an opinion (must be objective)

What is an inference?

a guess about an object or outcome based on your observations; you can make many inferences from a single observation

What can observations be?

either qualitative or quantitative

What is a qualitative observation?

describes qualities

What is a quantitative observation?

uses numbers to measure something

What is precise data?

how close your measurements are to each other (is this data consistent? Is the data specific?)

What is accurate data?

how close your measurement is to the correct/accepted value (is the data correct? Give the most accurate data)

What does conducting background research lead to?

defining the purpose/objective for the experiment

What is the overall goal of a scientific investigation?

to answer a question

What is the general path to defining a purpose?

our observations lead to questions, lead to research (what has already been found out about this question), leads to defining a purpose

What is a purpose/objective?

a statement that clearly shows what question you are trying to answer in your investigation

What is a hypothesis?

a testable prediction based on observations that describes a cause and effect relationship between variables

What is the format for a hypothesis?

“If (IV) then (DV) iv= independent variable= cause dv=dependent variable=effect

What is an independent variable?

what the experimenter will deliberately change or manipulate in the investigation; is usually on the x-axis of a graph; should be the only thing different between experimental groups

What is a dependent variable?

what changes in response to the independent variable; on the y-axis of a graph; usually represented by the data you collect in an investigation/what is measured

What should the materials include?

what you need to conduct the experiment; includes amounts, brands (if important), are as specific as possible, and are written as a bulleted list

What should the procedures include?

every step that was taken so that someone could replicate the experiment, starts with an action word, and is a numbered list

What is the experimental group(s)?

groups that are being tested

What are the control groups?

groups used for comparison with your experimental groups (the “normal” group)

What are constants?

the aspects of an experiment that are held constant/consistent to ensure that all aspects of trials are identical (minus the IV) and that any difference measured in the DV is caused only by the IV

What do results include?

the data collected during an investigation in an organized form, presented in an easy to read way, such as a graph

What do analyses include?

statements about what the data show, highlight any trends or patterns seen in the data and discuss any potential errors in the data

What does having as many repeated trials as possible do?

ensures the results aren’t by chance, eliminates any errors, and ensures the data is precise

How do you draw conclusions and communicate them?

make an explicit statement about whether your hypothesis was supported or rejected by your experimental data (may support or fail to support your prediction but data does not prove/disprove), describe any real world applications/uses for the information learned from the investigation

What is science?

leads to the advancement of knowledge, answers questions based on our observations

What is technology?

leads to the advancement of society, solves problems based on our needs, the application of scientific discoveries to meet human needs and goals through the development of products and processes

What is engineering?

applies scientific and mathematic principles to solve problems (science plus technology field)

What is problem identification?

clearly defines the problem or need

What is solution design?

brainstorm, research, sketch, and narrow down to the best design for product or process all within constraints such as: cost and time effectiveness, materials (availability, durability, environmentally conscience, etc). The perfect design is never possible but the benefits outweigh the risks

What is implementation?

build and test, continually making improvements

What is evaluation?

determine if you solved the problem and met all of the constraints of the project

What are the 4 steps to technological design?

1. problem identification

2. solution design

3. implementation

4. evaluation

What is matter?

anything that has mass and occupies space and is composed of atoms

What is an atom?

the smallest part of an element that still has the properties of that element

What are the 6 elements necessary for life?

C,H,O,N,P,S

What is a cell?

the most basic unit of life

What are atoms made of?

subatomic particles

Where are the subatomic particles located?

protons and neutrons in the nucleus and electrons in the electron cloud

Where is the majority of an atom’s mass?

in the positively charged nucleus

Where is the majority of an atom’s volume?

in the negatively charged electron cloud

What can we gather from the periodic table?

elements’ symbols, atomic number, average atomic mass, etc

What is an element’s atomic number?

the number of protons that can identify the element and equals the number of electrons in a neutral atom

What is average atomic mass?

the sum of protons and neutrons in the most common isotope of the element

What is an isotope?

2 or more forms of the same element, with different numbers of neutrons (written as the element’s name, mass number- protons + neutrons, or as the symbol)

What is the electron cloud divided into and how many electrons do they hold?

energy levels, or shells. The innermost level holds up to 2 electrons and the rest hold up the 8

What are the electrons in the outermost energy level called?

valence electrons

What does the group (columns) number of a periodic table tell?

how many valence electrons an atom has

What does the period (row) number of a periodic table tell?

how many energy levels an atom has

What do all atoms want/ what does that mean?

they want to be stable so they need full energy levels of electrons

How do atoms get full levels of electrons?

they form chemical bonds to make compounds

What is a compound?

2 or more atoms of different elements bonded together

What is a molecule?

2 or more atoms covalently bonded together

How do covalent bonds occur?

when nonmetallic atoms share electrons

How do ionic bonds occur?

when electrons are transferred from a metal to a nonmetal

What forms a cation?

when an atom loses an electron and becomes more positively charged

What forms an anion?

when an atom gains an electron and becomes more negatively charged

What is water?

a molecule made of 2 atoms of hydrogen covalently bonded to 1 atom of oxygen, is critical for all of life’s processes and has special properties because its polar

What is a polar molecule?

unequal distribution of charges, one side is more positive, one is more negative and dissolves in water

What is a non polar molecule?

no separation of charge, no positive or negative poles are formed, doesn’t dissolve in water

Why can a water molecule be attracted to each other?

it has hydrogen bonding

What holds water molecules together internally?

stronger covalent bonds

What holds different water molecules together externally?

weaker hydrogen bonds

What are the 5 properties of water?

1. cohesion

2. adhesion

3. high specific heat

4. less dense as a solid

5. water is a terrific solvent

What is cohesion?

the attraction between molecules of the same substance; tendency of molecules of the same kind to stick together, causes high surface tension

What is surface tension?

measure of how difficult it is to stretch or break the surface of a liquid/resist an external force

What is adhesion?

the type of attraction that happens between 2 different molecules, forms stronger bonds than cohesion

What is high specific heat?

the temperature of water does not change easily; it has to absorb more heat energy to increase overall temperature compared to other compounds

What are some of the benefits of water having a high specific heat?

it helps regulate cell temperatures in organisms, allows life to live in water, buffers large fluctuations in temperature which keeps Earth’s climate moderate

What does it mean if water is less dense as a solid?

ice is less dense than liquid water so it floats in liquid water (this means life can exist under frozen surfaces of lakes/polar seas)

What is a solution?

uniform mixture of two or more substances

What is a solute?

what gets dissolved

What is a solvent?

what does the dissolving

Why is water good at dissolving things?

it is polar

Why is water considered the universal solvent?

it dissolves more substances than any other liquid

What does hydrophilic mean?

has an affinity for water (water “loving”), usually dissolves easily in water (example: salt)

What does hydrophobic mean?

does not have an affinity for water (water “fearing”), does not dissolve in water (example: oil)

What are macromolecules?

large organic molecules that make up all living things

What are the 4 macromolecules?

carbohydrates, lipids, proteins, and nucleic acids

What are macromolecules made of structurally?

polymers made of monomers

What are monomers?

small basic sub units

What are polymers?

larger more complex structures made of monomers

What is a dehydration reaction?

builds a polymer by linking monomers (does this by removing a water molecule: both monomers have a hydroxy group, pull out OH from one and H from another to form water, oxygen to bond 2 monomers to form polymer)

What is hydrolysis?

breaks big polymers into smaller monomers by adding water, which breaks bonds

What is lysis?

breaking apart water

What is the main function of a carbohydrate?

short term energy storage

What are other uses of a carbohydrate?

structure, transport, signaling

What are carbohydrates found in?

sugars and starches

What are carbohydrates composed of?

C,H,O

What is the monomer of a carbohydrate?

monosaccharides (single sugar molecules)

What is the polymer of a carbohydrate?

polysaccharides (larger sugar molecules)