Biology test study guide

Ecosystem

Ecosystem

a biological community of
interacting organisms and their physical
environment

Food chain

a simple diagram that shows one way energy flows
through an ecosystem

Food web

a more complex diagram that consists of many
overlapping food chains

Nutrient density

a measure of the nutrients in a food compared with the energy the food provides

Matter

anything that has mass and takes up space/everything around you

Mass

the amount of matter in an object

Volume

the amount of space something takes up

Atoms and what they're made of:

Atoms are building blocks made up of protons, neutrons, and electrons

Elements

the alphabet in the language of molecules

Molecule

the general term used to describe any atoms that are connected by chemical bonds

Macromolecule

larger molecules that can work together

Solids

a state of matter that keeps its shape, the particles attach to one another and vibrate

Liquids

a state of matter that conforms to the shape of a container in which it is held, the particles are close to each other and flow

Gases

a state of matter in which particles are usually very far apart from one another, move very quickly, and aren't attracted to one another

Physical changes with example

a change to the physical properties of a substance
Ex: ice melting into water, then boiled into water vapor

Chemical changes and example

when one chemical substance is transformed into one or more different substances
Ex: cooking or baking

Nuclear energy

energy found in atoms

Thermal energy

the movement of molecules

What type of energy is energy in atoms?

Nuclear energy

Potential energy

stored energy

1st law of thermodynamics

Energy cannot be created or destroyed, the amount of energy in the universe is constant

Energy

the ability to do work or produce heat

Work

when a force acts on something causing it to move

Heat

a transfer of energy by thermal interactions

Internal energy of a system

the sum of that systems kinetic and potential energy

Law of conservation of matter

matter cannot be created or destroyed in a chemical reaction

Reactants

starting materials in a chemical reaction

Products

the result in a chemical reaction

What are the biological processes of life?

growing, offspring, survival, digestion, metabolism, heat, wastes, hair, etc.

How much energy is passed on when an organism consumes another?

10%

How much energy is lost when an organism consumes another?

90%

How energy flows through an ecosystem:

the sun -- producers -- primary consumers -- secondary consumers

positive delta E

gaining energy from the surroundings to a system. Work is done ON the system or heat is transferred TO the system from its surorundings

negative delta E

losing energy from the system to the surroundings. Work is done BY the system or heat is transferred FROM the system to the surroundings

Explain the difference between a food chain and web:

A food chain is a diagram that shows ONE way energy flows through an ecosystem, while a food web shows MULTIPLE

Do scientists prefer food chains or webs? Why?

foods webs; they're more realistic as energy flows in many ways in the real world

What are the effects of having too little/too much of a nutrient?

You cannot survive. Symptoms: fatigue, muscle cramps, disease, weight fluctuations, hair loss, depression, heart abnormality, etc.

How does matter move through an ecosystem:

matter cycles through different organisms. Chemicals travel through ecosystems and are released as heat.

Gas

a state of matter in which the atoms are very far apart, move quickly, and aren't attracted to each other

Liquid

a state of matter that conforms to the shape of the container their in; the atoms are close to each other and flow

Solid

a state of matter that keeps its shape; the atoms vibrate against one another very quickly

System

What you're studying

Surroundings

everything outside the system that allows the amount of energy in that system to change

Endothermic reactions:

reactions that absorb heat energy

Exothermic reactions:

reactions that release heat energy

Balance chemical equations

the amount of reactants and products need to be balanced in chemical equations on either side

Calcium

maintains bones and teeth; deficiencies can be caused by parathyroid glands; symptoms include muscle cramps, numbness, abnormal heart, tooth decay and gum disease

Iron

a component of hemoglobin, a protein in red blood cells that carry oxygen; deficiency symptoms are pale skin, fatigue, restless leg syndrome, dizziness, bruising. caused by periods, pregnancy, poor diet

Iodine

deficiency symptoms include dry skin, thin hair, weight gain, fatigue, brain frog, irregular periods. Caused by poor diet and soil

Magnesium

symptoms include osteoporosis, high blood pressure, nausea, clogged arteries, diabetes, heart disease

Vitamin A

stabilizes metabolism, promotes cell division, healthy eyes, skin, and immune system. Symptoms: night blindness, skin irradiation, stunted growth, eye conditions

Vitamin D

comes from sunlight, symptoms: hair loss, pale skin, bone pain, sleep issues, depression, no appetite. 42% of US population suffers from it

What type of energy is the movement of molecules?

thermal

What type of energy is stored in the bonds of molecules?

Chemical