Biolgoy Chapter 2 The Chemcial Composition Of Life

Question 1

Matter

Answer 1

Consists of chemical elements alone and in combinations called compounds

Question 2

Chemical bonds

Answer 2

Required to form molecules and for the molecules to have functions

Question 3

Chemical reactions

Answer 3

Make and break bonds

Question 4

Elements are defined

Answer 4

By the number of protons they have

Question 5

What are the subatomic particles for Proton, Neutron and electron

Answer 5

Proton: positive charge, Neutrons: no charge/Neutral Electrons: Negative charge

Question 6

Number of Subatomic Particles

Answer 6

Give lady each element it’s distinct characteristics

Question 7

Isotopes

Answer 7

All atoms of an element have the same number of protons but differ in number of neutrons

Question 8

Radioactive isotopes

Answer 8

Decay spontaneously, giving off particles and energy

Question 9

Radioactive tracers

Answer 9

Can be used to visualize cancer with imaging techniques

Question 10

Why would an isotope accumulate in cancerous cells?

Answer 10

Can be used to look at organ function like: kidneys and Gall bladder

Question 11

Radiometric dating

Answer 11

Determines how old something is based on the amount of daughter vs parent isotope

Question 12

Half life

Answer 12

Is the time it takes 50% of the isotope to decay from the parent into daughter form

Question 13

Compounds

Answer 13

Have properties that are distinct and different from the elements that compose them

Question 14

What percentage of 92 natural elements are essential to life

Answer 14

20-25%

Question 15

What makes up 96% of living matter

Answer 15

Carbon hydrogen, oxygen, nitrogen

Question 16

Trace elements

Answer 16

Are those required by an organism in only minute quantities

Question 17

What two elements that are toxic to most organisms

Answer 17

Arsenic and Lead

Question 18

Energy

Answer 18

Is the capacity to cause change

Question 19

Potential energy

Answer 19

Is the energy that matter has because of its location or structure

Question 20

Electron shell

Answer 20

Is an electrons state of potential energy which is also called energy level

Question 21

Orbital

Answer 21

Is the shape an electron makes in 3 dimensional space as it moves around the nucleus

Question 22

Moving closer to the nucleus

Answer 22

Releases energy

Question 23

Moving away from the nucleus

Answer 23

Requires energy

Question 24

Valence electrons

Answer 24

Are those in the outermost shell or valence shell

Question 25

The chemical behavior of an atom is mostly determined by the

Answer 25

Valence electrons

Question 26

Elements with a full valence shell are

Answer 26

Are chemically inert

Question 27

Molecule

Answer 27

When two or more elements are held together by chemical bonds which are held together by covalent bonds

Question 28

Electronegativity

Answer 28

How much an atom attracts the electrons within a covalent bond

Question 29

Non polar covalent bonds

Answer 29

Is when electrons shared evenly between two atoms

Question 30

A polar covalent bond

Answer 30

When one atom of an element holds onto the electron for longer than the other element

Question 31

Cation (ionic bonds)

Answer 31

Positive gave up the electron

Question 32

Anion (ionic bonds)

Answer 32

Negative took the electron

Question 33

ion

Answer 33

Is a charged atom

Question 34

Ionic bonds

Answer 34

Is the attraction between a cation and an anion they are usually found in salt

Question 35

Weak chemical bonds

Answer 35

Are indispensable and have many large biological molecules are held

Question 36

Hydrogen bond

Answer 36

Is a weak bond between a partially positive H+ and partially negative atom

Question 37

Molecules are composed of elements

Answer 37

Covalent my bonded together

Question 38

Compounds

Answer 38

Are molecules that contain at least two different elements

Question 39

Molecular shape determines

Answer 39

How biological molecules specifically recognized and respond to one another

Question 40

Reactants

Answer 40

Are the starting molecules of a chemical reaction

Question 41

Products

Answer 41

The final molecules of a chemical reaction

Question 42

Chemical equilibrium is

Answer 42

Reached when the forward and reverse reactions occurs at the same rate