chapter 2: the chemistry of life bio 121. chemistry is relevant… (even if we don’t like it)
TRANSCRIPT
CHAPTER 2: The Chemistry of Life
BIO 121
Chemistry is relevant…(even if we don’t like it)
Understanding biology is impossible without an introduction to chemistry.
Learning Outcomes
• Explain the chemical nature of biological molecules
• Identify the primary elements in living organisms
• Describe the structure of atoms• Compare and contrast the different types of
bonds• Differentiate between atoms, molecules, and
compounds
Learning Outcomes
• Explain how the structure of water affects its chemical properties
• Explain how acids and bases affect pH• Explain how monomers are used to form
polymers• Compare and contrast the structure and
function of the four classes of biological molecules
2.1 Atoms Make Up All Matter
• Matter– Takes up space
• Energy– Ability to do work
Matter
Elements
All people (and things) are made up of matter
Everything is made up of matter…
• Matter? What’s the matter wit you?– Anything that takes up space and has
mass
• Many different forms of matter:– Rocks– Metals– Oils– Gases
2.1 Atoms Make Up All Matter
• A. Elements Are Fundamental Types of Matter– Element cannot be broken down– Periodic table– Bulk elements
• 25 elements essential to life• Minerals• Trace elements
Figure 2.2 The Periodic Table of Elements.
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
H
1
3
11
K
19
37
55
87
4
12
20
38
56
88
21
Y
39
La
57
Ac
89
Ti
22
Zr
40
Hf
72
Rf
104
V
23
Nb
41
Ta
73
Db
105
Cr
24
Mo
42
W
74
Sg
106
Mn
25
Tc
43
Re
75
Bh
107
Fe
26
Ru
44
Os
76
Hs
108
Co
27
Rh
45
Ir
77
Mt
109
Ni
28
Pd
46
Pt
78
Ds
110
Cu
29
Ag
47
Au
79
Rg
111
Zn
30
Cd
48
Hg
80
Uub Uut Uuq Uup Uuh
112 113 114 115 116
B
5
AI
13
Ga
31
In
49
Tl
81
C
6
Si
14
Ge
32
Sn
50
Pb
82
N
7
P
15
As
33
Sb
51
Bi
83
O
8
S
16
Se
34
Te
52
Po
84
F
9
Cl
17
Br
35
I
53
At
85
He
2
Ne
10
Ar
18
Kr
36
Xe
54
Rn
86
Bulk elements
Trace elementsPossibly essential trace elementsLi
Na
Rb
Cs
Fr
Be
Mg
Ca
Sr
Ba
Ra
Sc
Basic ingredients for all things
Elements
• Fundamental substance• Can’t be broken down into a simpler
substance• Examples include – Carbon, Oxygen,
Hydrogen, Calcium, Gold, Iron, Silver
Image Source:http://education.jlab.org/qa/pen_number.html
Elements essential for life:
• Carbon• Oxygen• Hydrogen• Nitrogen
• Calcium• Phosphorus• Potassium• Sulfur• Sodium• Chlorine• Magnesium
96% of living matter
2.1 Atoms Make Up All Matter
• B. Atoms Are Particles of Elements– Atom
• Protons– Atomic number
• Neutrons• Electrons
Atoms
• Smallest unit of matter that still retains all the properties of an element
• Made up of protons (+), neutrons and electrons (-).
• Neutrons and Protons form atomic nucleus (dense core)
• Electrons form a cloud around the nucleus moving at nearly the speed of light
Image Source: http://www.hk-phy.org/articles/laser/laser_e.html
Figure 2.3 Atom Anatomy.
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Electron (e)
Nucleus
6 protons (p)
6 neutrons (n)
6 total
2.1 Atoms Make Up All Matter
• C. Isotopes Have Different Numbers of Neutrons– Mass number
• Protons plus neutrons
– Isotope• 12C• 13C• 14C• Radioactive
CCarbon
Atomic numberElementSymbol
Atomic mass
6
12.0 112
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Question
• The mass number tells usA. The number of protons onlyB. The number of electrons onlyC. The number of protons and electronsD. The number of protons and neutrons