Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
63 Cards in this Set
- Front
- Back
What is chemistry? |
The science that deals with matter's composition and properties. Used to understand normal and abnormal body function.
|
|
What is matter?
|
The stuff from which the universe is made. Takes u space and has weight. Can be in different states - solid, liquid or gas.
|
|
What are elements?
|
92 are found in nature. Identified by names, chemical symbols and by a number. They are described and organized on the periodic table
|
|
What are atoms?
|
Smallest subunits of elements. Cannot be broken down or changed by ordinary chemical and physical means. Consists of electrical particles.
|
|
What are atoms constructed from?
|
A nucleus which is composed of protons and neutrons, and electrons which orbit around the nucleus.
|
|
What are the charges of protons,neutrons and electrons?
|
-positive
-neutral -negative |
|
How is the atomic number of an element determined?
|
It is equal to the number of protons in an atom's nucleus, also represents the number of electrons orbiting the nucleus.
|
|
What are energy levels?
|
Regions around an atom's nucleus where the electrons orbit.
|
|
How many electrons can be in the first energy level?
|
2
|
|
How many electrons can fit in the 2nd energy level?
|
8
|
|
When is the atom most stable?
|
When it's energy levels are filled with electrons.
|
|
An atom will form ________ _______ with other atoms to fill its outermost energy level.
|
Chemical bonds.
|
|
What is an ion?
|
A charged atom
|
|
What is a cation?
|
A positively charged ion
|
|
What is an anion?
|
A negatively charged ion
|
|
When is an ionic bond formed?
|
When one atom transfers electrons to another atom.
|
|
What are electrolytes?
|
Compounds that separate into ions in a solution. Term used to refer to ions themselves.
|
|
What do ions do in the body?
|
Play important physiologic roles in body. Homeostatic maintains proper ion concentration. Ions conduct electric currents in body fluid. Measurement of a tissue's electrical activity is used to diagnose disease.
|
|
What is a covalent bond?
|
Forms when 2 atoms share electrons.
|
|
What is a nonpolar covalent bond?
|
Electrons are shared equally.
|
|
What is a polar covalent bond? |
Electrons are shared unequally, has positive and negative ends of the atom. |
|
What is a hydrogen bond? |
Often occur between different molecules, the positively charged hydrogen portion of a polar molecule is drawn to the negatively charged portion of another polar molecule. |
|
What is intermolecular? |
A weak bond formed between 2 molecules. |
|
What is intramolecular? |
A bond formed between different portions of a large molecule, within a molecule. |
|
What are molecules? |
Combination of atoms. Chemicals composed of 2 or more atoms held together with a bond. |
|
What is a chemical reaction? |
When chemicals react when mixed, and are fundamentally changed and make new substances. A process by which atoms or molecules form new combinations. |
|
Reactants |
Atoms/molecules present before the reaction takes place. |
|
Products |
The resulting new atoms/molecules after a chemical reaction. |
|
What are compounds? |
Chemicals composed of 2 or more different atoms bonded together. A molecule of a compound is the smallest possible unit of that compound. |
|
what is a mixture? |
A blend of 2 or more chemicals, elements, or ions. |
|
Homogenous |
Component substances cannot be distinguished from each other and remain evenly distributed; uniform. |
|
Heterogenous |
A no uniform mixture. |
|
Solvent |
A substance in which something is dissolved |
|
Aqueous solution |
a solution in which water is the solvent |
|
Solute |
a substance that is dissolved in a solvent |
|
Solution |
Homogenous mixture of a solute dissolved in a solvent |
|
Suspension |
Heterogenous mixture that will separate unless shaken |
|
Colloid |
Heterogenous mixture in which suspended particles remain distributed because of their small size. (Not moving) |
|
What is the importance of water in the body? |
most abundant compound in the body critical in all physiologic processes deficiency (dehydration) threatens health participates in body's chemical reactions universal solvent as almost everything dissolves in water. |
|
Hydrophilic |
Water loving substance, readily mixes with water |
|
Hydrophobic |
Water repellant, does not readily mix with water |
|
What is an acid? |
A substance that donates hydrogen ions "proton donors". Releases electrons leaving just the protons. Positively charged. |
|
What is a base/alkali? |
a substance that donates hydroxide ions and accepts hydrogen ions. "Proton acceptors" |
|
What is a salt? |
A substance formed by a reaction between an acid and a base. It's a neutralization reaction. |
|
What is the pH scale? |
Measures the relative concentrations of hydrogen and hydroxide ions in a solution. Scale from 0 (most acidic) to 14 (most basic) |
|
What is the normal range of pH of body fluid? |
7.35 - 7.45 |
|
What is a buffer? |
Chemicals that prevent sharp changes in H+ Concentration. Important in maintaining a relatively constant pH in body fluids |
|
What are isotopes? |
forms of an element that have the same atomic number but different atomic weight. Different atomic weight because of different number of neutrons. Can be stable or unstable (radioactive) |
|
What is radioactivity? |
emission of atomic particles from an isotope. |
|
What are the uses of radioactive isotopes? |
Used in the treatment of cancer - radiation penetrates and destroys tumor cells used in diagnosis - X-Rays penetrate tissue and produce an image on film |
|
How many elements does living matter contain? |
26 of 92 elements are present in living matter |
|
What are the 4 elements that make up 96% of body weight? |
Hydrogen Oxygen Carbon Nitrogen |
|
How many elements are present in 4% of the body weight? |
9 elements |
|
What are organic compounds? |
Chemical compounds found in living things. built on the element Carbon. |
|
What are the main types of organic compounds? |
Carbohydrates Lipids Proteins Nucleotides |
|
What are carbohydrates? |
Sugars. types are monosaccharides, disaccharides and polysaccharides. |
|
What are the types of lipids in the body? |
Triglycerides, phospholipids, and steroids |
|
What are triglycerides? |
Simple fat composed of glycerol and 3 fatty acids. insulate body, protect organs, and stores energy. |
|
What are phospholipids? |
Complex lipid containing phosphorus. main component of cell membranes |
|
What are steroids? |
Contains rings of Carbon atoms. regulates body function |
|
What are proteins? |
Contain nitrogen (and sometimes sulfur and phosphorus). Found as structural materials and metabolically active compounds. Are both structural and functional. Composed of chains of amino acids held together by peptide bonds. |
|
What are enzymes? |
functional proteins, proteins that speed up or catalyze chemical reactions. work on specific substrates. Are not used up or changed in a chemical reaction. Work via lock-and- key mechanism. Only denaturalizes in harsh conditions (ex: extremes in tempuratues or pH) |
|
What are nucleotides? |
Composed of a nitrogenous base, a sugar, and a phosphate group. Is building blocks of DNA and RNA one type is a component of ATP. |