Environmental Biology
for Engineers and Scientists
D.A. Vaccari, P.F. Strom, and J.E. Alleman
© John Wiley & Sons, 2005
Chapter 4 – The Cell
Chapter 5 – Energy and Metabolism
Figure 4-1. Example prokaryotic cell structure
cell membrane
ribosomes
cell wall
cytoplasm
flagellum
granules
nucleoid
thylakoid membrane
Figure 4-2. Diagram
of a plant cell and an
animal cell.
[From Schaum’s
Biology]
Figure 4-3. Plasma membrane structure.
[Schaum’s “Human Anatomy and Physiology”]
Figure 4-4. Chromosome structure in eukaryotes. [Based on P&H.]
Scaffolding protein
Chromosome
Helical coil
Histone protein
DNA double helix
Figure 4-5. The
stages of mitotic
division
[Schaum’s Biology]
Figure 4-6. Example life cycle of sexual organisms.
Mitosis
SOMATIC CELLS
Diploid
GERM CELLS
Diploid
Mitosis
Meiosis
ZYGOTE
Diploid
GAMETES
Haploid
Fertilization
Figure 4-7. Meiosis: Crossing over and independent assortment of chromosomes.
Interphase: replication
One diploid cell
Meiosis I: crossing over and first division
Meiosis II: alignment and second division
Four haploid cells
Adenosine triphosphate (ATP) structure,
showing the high-energy phosphate bonds.
NH2
N
N
H
N
O
HO
P
OH
O
O
P
OH
O
O
P
O
CH2
O
OH
H
H
H
H
OH
OH
N
H
Figure 5-1. Typical behavior of single substrate-enzyme
reactions. [Based on Baily and Ollis]
(a)
(b)
0.25
0.35
rmax = k*Et
S = 1.5
0.25
r (mmols/L/s)
r (mmol/L/s)
0.30
S = 1.0
0.20
0.15
0.10
S = 0.5 mmol/L
0.05
0.00
0.20
0.15
0.10
r = r max/2
0.05
S = Km
0.00
0.0
0.2
0.4
Et (mmol/L)
0.6
0.0
1.0
2.0
S (mmols/L)
3.0
Figure 5-2. Substrate activation and inhibition.
r (mmol/L/s)
0.12
0.10
0.08
Inhibition
0.06
0.04
Activation
0.02
0.00
0.0
1.0
2.0
S (mmol/L)
3.0
4.0
Figure 5-3. Effect of pH on enzyme activity for various ranges of pKa.
1.2
pK: 4 - 10
[E] / [E]t
1.0
5-9
0.8
6-8
0.6
6.75 - 7.25
0.4
0.2
0.0
1
2
3
4
5
6
7
pH
8
9
10
11
12
13
Figure 5-4. Effect of temperature on hydrogen peroxide decomposition by catalase.
(a) E = 3.5 kcal/mol, ΔHd = 55.5 kcal/mol, ΔSd = 168 kcal/(mol-K), β = 258 mm3/min.
(b) Exponential fitted to equation in (a) at 20 and 25 deg C, r20 = 185.8 mm3/min, θ = 1.024 .
[Based on Baily and Ollis]
rmax  k  [E]t 
  T  exp( E / RT)
r  r20  
1  exp( S d / R )  exp(  H d / RT)
400
(b)
350
r (cu mm/min)
300
250
(a)
200
150
100
50
0
0
20
40
T (deg C)
60
80
T  20
Glycogen
or starch
All NADH2 and FADH2 produced go to the CYTOCHROME SYSTEM
Glycolysis
Glucose (C-6)
Figure 5-5.
2 ATP
CO2
(Nine
steps)
Glycolysis,
fermentation, and
the Krebs cycle.
Inputs and outputs
from each cycle
are shown, as well
as connections
with metabolism
of other
biochemical
compounds.
Transition to Krebs Cycle
4 ATP
2 NADH2
Each
Pyruvate x 2 (C-3)
Acetaldehyde (C-2)
pyruvate
Each
Fermentation
pyruvate
NADH2
NADH2
CoA-SH
Lactic Acid (C-3)
Fats
Acetyl-CoA
Oxaloacetic
Acid (C-4)
NADH2
Citric
Acid (C-6)
Malic Acid
Amino
Acids
Isocitric acid
KREBS CYCLE
Fumaric acid
CO2
FADH2
Succinic acid
-Ketoglutaric
acid (C-5)
Succinyl-CoA
(C-4)
ATP
GTP
CO2
NADH2
NADH2
Figure 5-6. Mitochondrion structure, showing membrane structure, division into
inner and outer compartments (e.g. Smith et al)
Figure 5-7. The cytochrome electron transport system, with relationship to
glycolysis and the Krebs cycle (based on Vander, et al and Martini, et al).
Cytoplasm
Glycolysis
Pyruvate
O2
Glucose
ATP
H2 O
Outer mitochondrial membrane
CO2
Inner mitochondrial membrane
ADP
+Pi
Outer compartment
Inner compartment
FAD
H2 O
Krebs
Cycle
NAD
NADH2
FMN
2e-
2H+
2H+
FADH2
2H+
CoQ
H+
2e- Cyt
b
Cyt
c
2H+
2H+
Cyt 2ea3
Cyt
a
2H+
ATP
synthase
Figure 5-8. Structure of a chloroplast. [Schaum’s Biology]
Figure 5-9. Photosynthetic apparatus.
[Schaum’s Biology]
Figure 5-10. Structure of chlorophyll a and chlorophyll b.
R
O
N
Chlorophyll a : R = CH3
N
O
Mg
N
O
N
O
O
Chlorophyll b : R = CHO
Figure 5-11. Absorption spectrum of chlorophyll and of a green leaf, and action
spectrum for rate of photosynthesis versus wavelength. [Baily and Ollis]
Standard electrode potential, mV
Figure 5-12. Noncyclic photophosphorylation.
-800
-600
-400
-200
0
200
400
600
800
1000
1200
1400
1600
NADPH
P430
NADP
2e-
Cyclic photophosphorylation
ATP ADP
P700
Z
Cyt b563
Photosystem
I
1/2O2
2eH2O
P680
Two
photons
Two
photons
Photosystem
II
2H+
12ATP
12 Molecules of
3-Phosphoglycerate
(C-3)
6 Molecules
of CO2
(Photorespiration)
12ADP
The Calvin Cycle
O2
12 Molecules of
1,3-diphosphoglycerate
(C-3)
6 Molecules of
Ribulose 1,5-diphosphate
(C-5)
12 NADPH
Figure 5-13.
CO2
fixation.
10 molecules
PGAL
12ADP
[Based on
Raven]
12 Molecules of
Glyceraldehyde
3-phosphate
(PGAL) (C-3)
12ATP
2 molecules
PGAL
Carbohydrate Synthesis
(glucose, sucrose, starch)
12 NADP