Chapter 1-2+ some of 3: Exam 1 Flashcards
All forms of matter are composed of…
Chemical elements-substances that cannot be split into simpler substances by ordinary chemical means
What are the abbreviations elements are given called?
Symbols
What makes up 96% of body weight?
Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N) CHON
What are units of matter of all chemical elements called?
Atoms
What does an Atom consist of?
A nucleus, which contains positively charged protons and neutral (uncharged) neutrons, and negatively charged electrons
Where do electrons spend most of their time?
Shell
How many electrons can each shell hold?
The first nearest to the nucleus, 2, the second shell, 8, the third shell 18, and the fourth shell 18, and so on
What is the neutral element rule?
The number of electrons in an atom of a neutral element always equals the number of protons
What is the mass number of an atom?
The total number of protons and neutrons
What are Isotopes?
Same number of protons but different numbers of electrons
What are unstable isotopes called?
Radioactive isotopes
What is a radioactive isotope?
Nuclei decay to form a simpler and thus more stable configuration. Can be used to study both the structure and function of particular tissues
What is atomic mass?
Average mass of all its naturally occurring isotopes and reflects the relative abundance of isotopes with different mass numbers
What is included in atomic mass?
Ions, molecules, free radicals, and compounds
What happens when an atom gives up or gains electrons?
It becomes an ion
What is a cation?
Positive charge
What is an anion?
Negative charge
What is a molecule?
When two or more atoms share electrons
What is a free radical?
Electrically charged atom or group of atoms with an unpaired electron in its outermost shell
What is a compound?
A substance/molecule made of two or more different elements
Octet Rule:
8 valence electrons for each atom to fulfill the valence shell
The atoms of a molecule are held together by forces of attraction called…
Chemical bonds
Ionic bonds…
When the force of attraction holds ions having opposite charges together-opposites attract
Carbon Compounds:
- Reacts to one or several hundred other carbon atoms to form large molecules of many shapes
- Do not dissolve easily in water
- Used for building body structures
- Held together by covalent bonds
- Decompose easily, good source of energy
When two monomers join together…
Dehydration synthesis
Macromolecules break down into monomers…
Hydrolysis
What are isomers?
Molecules that have the same molecular formula but different structures
What provides the most of energy needed for life?
Carbohydrates, which includes, sugars, starches, glycogen, and cellulose
What are the three major groups of carbohydrates?
monosaccharides, disaccharides, and polysaccharides
The simple sugars
Monosaccharides and disaccharides
Monosaccharides:
Contain three to seven carbon atoms and include glucose, a hexose that is the main energy supplying compound of the body
Disaccharides:
Formed from two monosaccharides by dehydration synthesis, can be split back into simple sugars by hydrolysis
What produces Sucrose?
Glucose and fructose
What are the largest carbohydrates?
Polysaccharides, and they may contain hundreds of monosaccharides
The principle of polysaccharide in the human body is…
Glycogen, stored in the liver and skeletal muscles
Contains carbon, hydrogen, and oxygen…
Lipids
Lipids have:
Fewer polar covalent bonds and thus are mostly insoluble in polar solvent such as water ( they are hydrophobic)
Acidic+basic=
Zwitterion
What forms triglycerides?
Fatty acids, and provide cellular energy
Fatty acids can be _, with only single covalent bonds, and unsaturated, with _ or more double covalent bonds
Saturated, one
Glycose is to..
Humans
Starches is to…
Plants
Provides protection, insulation, and energy
Triglycerides
At what temperature can a triglyceride become a solid or oil?
Room temperature
Triglycerides provide more than _ as much energy
Twice as much energy as a carbohydrate or protein
True or False: Triglycerides storage is virtually unlimited
True
What makes up a triglyceride?
Glycerol and Fatty Acids
