Bio

science

the study of the natural world

scientific method

the technique used to study the natural world

5 steps of scientific method

make an observation


1. Define a Question to Investigate. As scientists conduct their research, they make observations and collect data. ...
2. Make Predictions. Based on their research and observations, scientists will often come up with a hypothesis. ...
3. Gather Data. ...
4. Analyze the Data. ...
5. Draw Conclusions.

hypothesis

a testable statement that predicts the results expected from a research study; often written as if... then statement

example of hypothesis

If parsley is grown in varying moisture levels, then the parsley grown in dry conditions will grow best.

data

information you observe or record

qualitative data

is observed but not measured (descriptions); ex: type of car, food choices

quantitative data

data are numbers (measurements); ex: age, weight

survey or an experiment

we can test a hypothesis by a

in a survey, we collect data about conditions that \______ or about events that \_______.

already exists, already happened

examples of surveys

what students ate for breakfast

examples of an experiment

grow parsley in various conditions

examples of ways to analyze data include

calculation, graph, and table

science only deals with the physical world and things that can be

observed and measured

scientists cannot tell us answers to questions that have to deal with

spiritual, orality, or meaning of life

human and can make mistakes

scientific studies may hav errors- scientists are

bias

scientist may also have a influenced \____, which is what they want to happen or already think will happen.

example of bias

Hershey funding a study of benefits of chocolate

atoms

all matter is composed of tiny particles

nuetrons, protons, and electrons

atoms are composed of

nucleus

the center of the atom is called; also the control center of a cell which controls a persons DNA

neutron

have no charge (neutral) and are found in the nucleus of an atom

protons

have a charge of +1 and are found within the nucleus of an atom

electrons

have a charge of -1 are found orbiting the nucleus

molecule

consists of two or more atoms bonded together

ionic bond

when an atoms gives up one or more electrons to another atom

ion

charged atoms or molecules

example of a molecule

Na Cl (table salt)

covalent bond

atom shared electrons

example of covalent bonds

O2 (oxygen gas) O\=O

energy

the ability to do work; cells need this for many essentail processes

kinetic energy

energy of motion

motion

all particles have a certain amount of kinetic energy and are thus in constant

diffusion

the net movement of atoms or molecules from an area of high concentration to an area of lower concentration

examples of diffusion

drop of food dye in water; small spreading

potential energy

energy of position (stored energy)

created or destroyed

energy can change forms but cannot be

1st law of thermodynamics

energy cannot be created or destroyed

enzyme

is a protein that helps reactions get started; essentail for life

acid

has a pH is less than 7

neutral

a substances with a pH of 7

base

has a pH that is greater than 7

lipids, proteins, carbohydrate, and nucleic acids

the four main groups of important biological molecules include

carbohydrates

sugar such as glucose (blood sugar) and sucrose (table sugar)

glycogen (how animals store sugar), starch (how plants store sugar), and cellulose (forms structural features of plants, like the cell wall)

larger carbohydrates

lipids

generally do not mix well with water; animal store excess energy (calories) in the form

Amino acids

proteins are made up of building blocks called

protein

a long chain of amino acids folded together; can only function in that specific shape

nucleic acids

include DNA (deoxyribonucleic acid) and RNA (ribonucleic acid acid)

DNA

contains the organisms genetic code, which directs all of the cell's activities

RNA

carries information from DNA and uses it to guide protein synthesis

cells

all living organisms are composed of one or more

unicellular

organisms composed of just one cell are called

examples of unicellular

bacteria, amoeba, and yeast

multicellular

organisms composed of many cells are called

examples or multicellular

plants, animals, and people

eukaryotic and prokaryotic

the two major classifications of cells are

eukaryotic cells

have a membrane-bound nucleus and membrane-bound organelles

examples of eukaryotic cells

plants, animals, protists, and fungi

prokaryotic cells

have no true nucleus and no membrane-bound organelles

examples of prokaryotic cells

bacteria

cell membrane

all cells have one; separates the inside of the cell from the surrounding environment

phospholipids

the major component of all cell membranes; form the cell membrane steroids like cholesterol and certain hormones

phospholipids bilayer

the membrane is composed of two layers of these molecules

hydrophobic

water-fearing

hydrophilic

water-loving

cell wall

is a rigid structure located outside of the cell membrane which provides support and protection; animals and humans do not have this

nuclear membrane

surrounds the nucleus with a double membrane called

nucleolus

the site where the ribosomes are made

cytoplasm

includes everything inside the cell except the necleus

cytosol

the fluid part of the cytoplasm

mitochondria

break down sugar/food molecules to produce usable energy (ATP) for the cell

ribosomes

line up and connect amino acids to produce proteins

smooth ER

lacks ribosomes, helps produce steroid hormones and break down toxic substances

rough ER

dotted with ribosomes; modifies proteins and acts as a transportation network

golgi apparatus

like a post office; processes and packages cellular products

lysosomes

filled with digestive enzymes used to recycle cellular components, digests food, or destroys invading bacteria and viruses

cytoskeleton

system of fibers that give a cell structure and are important for movement

flagellum

a long, tubular extension of a cells membrane that aids in movement

cilia

short numerous extensions of cell membrane that aid in cell movement or in movement of fluids across a cell surface

chloroplast

contain the green pigment chlorophyll, which is important for photosynthesis

vacuoles

storage containers within the cell

central vacuole

holds water in plant cells

contractile vacuole

expels excess water from unicellular organisms

vesicles

small transport containers within the cell

semipermeable

that it is permeable to some substances but not to others

osmosis

diffusion of water across a semipermeable membrane is called

hypertonic fluid

causes cells to shrivel

hypotonic fluid

causes cells to swell and possible burst

isotonic fluid

for animal and human cells no change

homeostasis

the internal steady state that every organisms must maintain in order to live

Examples of homeostasis

pH, temperatures, and blood sugar

ATP (adenosine triphosphate)

the usable form of cellular energy

sun

the ultimate energy source for all things on Earth

photosynthesis

light energy is captured and used to make sugar molecules; examples: plants and algae

chemical equation for photosynthesis

light energy + CO2 + water -\> sugar + O2

chlorophyll

green pigment

light - dependent phase and Calvin cycle

2 phases of photosynthesis

light - dependent phase

Which of these two phases use light energy to produce ATP, NADPH, and O2?

Calvin cycle

Which of these two phases produce ATP, NADPH, and CO2 to form sugar (glucose)?