BIO 201 Connect Chapter 2

Weight of proton or neutron

1 amu

What is the avg. background radiation a person receives?

2.4 mSv per year

How much is fatal Sv?

5 Sv or more

nonpolar covalent

Covalent bond in which electrons are equally attracted to both nuclei. May be single or double. Strongest type of chemical bond.

Sievert (Sv)

SI unit of radiation dosage, takes account type & intensity of radiation and biological effect

van der waals force

Weak, brief attraction due to random disturbances in the electron clouds of adjacent atoms. Weakest of all bonds.

bones/teeth consist of?

calcium, phosphate, magnesium, fluoride, sulfate

mutagenic

causing mutations in DNA

Why are electrolytes important?

chemical reactivity, osmotic effects, electrical effects on nerve and muscle tissue

antioxidant

chemical that neutralizes free radicals

nucleus

composed of protons and neutrons

polar covalent

electrons are more attracted to one nucleus than to the other, may result in slightly positive or negative regions in molecule

ionizing radiation

high energy radiation emitted by radioisotopes ejects electrons from atoms, converting atoms to ions

minerals

inorganic elements extracted from soil by plants and passed up the food chain to humans and other organisms

colloids

mixtures of protein and water (albumin in blood plasma)

Possible effects from electrolyte imbalance?

muscle cramps, brittle bones, coma, cardiac arrest

radioactivity

process of decay

ionic bond

relatively weak attraction between an anion and a cation. Easily disrupted in water, as when salt dissolves

double covalent

sharing of 2 electron pairs. Often occurs between carbon atoms, between carbon and oxygen and between carbon and nitrogen

single covalent bond

sharing of one electron pair

covalent bond

sharing of one or more pairs of electrons between nuclei

electrolytes

substances that ionize in water (acids, bases, or salts) & form solutions capable of conducting electricity

atom

the number of protons in it's nucleus

physical half-life

time required for 50% of its atoms to decay to more stable isotope

biological half life

time required for half of it to disappear from the body

carcinogenic

triggering cancer as a result of mutation

Radioisotopes

unstable isotopes

Free radicals

unstable, highly reactive chemical particles with an odd number of electrons

hydrogen bond

weak attraction between polarized molecules or between polarized regions of the same molecule. Easily disrupted by temperature and pH changes