What is biology- study of life

Life

-6 characteristics

Virus is not living

Smallest part of any organism/ element Atom indivisible but can be converted into diff forms of

energy

Element Oxygen …substance that can’t be broken down into simpler substances

3 forms of oxygen O3.. O.. O2.. H2O

Atomic # oxygen- 8

Mass oxygen- 16

Atomic number characterizes all elements

7 nitrogen

6 carbon

Atomic number- bottom left (mass number top)

#protons and neutrons- atoms (cells surround nucleus) K, L, M cells

1st cell- 2 electrons

2nd cell- 8 electrons

Electrons negative charge. Protons positive charge

Deficiency/ valance- whatever is left in the shell (how much more it can hold.)

Oxygen has a -2 charge. 2 defeciency

Hydrogen deficiency can have a plus or minus

Carbon mass- 12—6 protons 6 neutrons L cell 4. Vacancy of 4 what determines what’s positive or neg.

Change on an element depends on its ability to give up or accept an electron

Alpha particles Beta Rays Gamma Rays

x- rays- manmade- take particle . accelerate particle. Energy from particle is an x- ray

Radioactive Elements- unstable elements normal neutrons. Nitrogen unstable. Needs to give up. Isotope

same protons diff neutrons

ATOM- Element- Isotope- Radioactive Elements

Alpha (- energy +) Gamma Rays 4x

Major- oxygen need it to breathe,

Hydrogen. Sodium,

Minor elements : zinc,

Radioactive isotope gives off energy

Compounds- union of two or more elements

Held together by bonds ^^

Covalent bonds- share of elements

Ionic bonds- held together by separate charges (– and +) NaCl