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Fig. 10-3a
Leaf cross section
Vein
Mesophyll
Stomata
Chloroplast
CO2
O2
Mesophyll cell
5 µm
Fig. 10-3b
Chloroplast
Outer
membrane
Thylakoid
Stroma
Granum
Thylakoid
space
Intermembrane
space
Inner
membrane
1 µm
Concept Map - Photosynthesis
Fig. 10-4
Reactants:
Products:
12 H2O
6 CO2
C6H12O6
6 H2O
6 O2
Oxidation & Reduction
The Splitting of Water
• Chloroplasts split H2O into hydrogen and
oxygen, incorporating the electrons of hydrogen
into sugar molecules
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
When light strikes an object:
• Transmitted
• Absorbed (primarily red & blue light)
• Reflected (green light)
3 major events occur during
photosynthesis
1. Absorption of light energy
2. Conversion of light energy to chemical
(ATP & NADPH)
3. Storage of chemical energy in sugars
These events occur during:
-light rxn. (events 1,2)
-dark rxn. (event 3)
Photosynthetic Pigments: The Light Receptors
• Pigments are substances that absorb visible light
• Different pigments absorb different wavelengths
• Wavelengths that are not absorbed are reflected
or transmitted
• Leaves appear green because chlorophyll reflects
and transmits green light
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 10-7
Light
Reflected
light
Chloroplast
Absorbed
light
Granum
Transmitted
light
Fig. 10-6
10–5 nm 10–3 nm
103 nm
1 nm
Gamma
X-rays
rays
UV
106 nm
Infrared
1m
(109 nm)
Microwaves
103 m
Radio
waves
Visible light
380
450
500
Shorter wavelength
Higher energy
550
600
650
700
750 nm
Longer wavelength
Lower energy
Fig. 10-5-4
CO2
H2O
Light
NADP+
ADP
+ P
i
Light
Reactions
Calvin
Cycle
ATP
NADPH
Chloroplast
O2
[CH2O]
(sugar)
• There are two types of photosystems in the
thylakoid membrane
• Photosystem II (PS II) functions first (the
numbers reflect order of discovery) and is best at
absorbing a wavelength of 680 nm
• The reaction-center chlorophyll a of PS II is called
P680
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
The Nature of Sunlight
• Light is a form of electromagnetic energy, also
called electromagnetic radiation
• Like other electromagnetic energy, light travels
in rhythmic waves
• Wavelength is the distance between crests of
waves
• Wavelength determines the type of
electromagnetic energy
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
• The electromagnetic spectrum is the entire
range of electromagnetic energy, or radiation
• Visible light consists of wavelengths (including
those that drive photosynthesis) that produce
colors we can see
• Light also behaves as though it consists of
discrete particles, called photons
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 9-2
Light
energy
ECOSYSTEM
Photosynthesis
in chloroplasts
CO2 + H2O
Organic
+O
molecules 2
Cellular respiration
in mitochondria
ATP
ATP powers most cellular work
Heat
energy
• C6H12O6 + 6 O2  6 CO2 + 6 H2O + Energy
• Energy = (ATP + heat)
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
The Stages of Cellular Respiration:
A Preview
• Cellular respiration has three stages:
– Glycolysis (breaks down glucose into two molecules
of pyruvate)
– The citric acid cycle (completes the breakdown of
glucose) or Krebs Cycle
– Oxidative phosphorylation (accounts for most of
the ATP synthesis) or ETC
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 9-6-3
Electrons carried
via NADH and
FADH2
Electrons
carried
via NADH
Citric
acid
cycle
Glycolysis
Pyruvate
Glucose
Oxidative
phosphorylation:
electron transport
and
chemiosmosis
Mitochondrion
Cytosol
ATP
ATP
ATP
Substrate-level
phosphorylation
Substrate-level
phosphorylation
Oxidative
phosphorylation
Concept 9.2: Glycolysis harvests
chemical energy by oxidizing
glucose to pyruvate
• Glycolysis (“splitting of sugar”) breaks down
glucose into two molecules of pyruvate
• Glycolysis occurs in the cytoplasm and has two
major phases:
– Energy investment phase
– Energy payoff phase
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
• In alcohol fermentation, pyruvate is converted
to ethanol in two steps, with the first releasing
CO2
• Alcohol fermentation by yeast is used in
brewing, winemaking, and baking
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings
Fig. 14-15b
1st generation
(grandparents)
2nd generation
(parents, aunts,
and uncles)
Ww
ww
ww
Ww ww ww Ww
Ww
Ww
ww
3rd generation
(two sisters)
WW
or
Ww
Widow’s peak
ww
No widow’s peak
(a) Is a widow’s peak a dominant or recessive trait?
Fig. 14-15c
1st generation
(grandparents)
Ff
2nd generation
(parents, aunts,
and uncles)
FF or Ff ff
Ff
ff
ff
Ff
Ff
Ff
ff
ff
FF
or
Ff
3rd generation
(two sisters)
Attached earlobe
Free earlobe
(b) Is an attached earlobe a dominant or recessive trait?
Fig. 14-3-3
EXPERIMENT
P Generation
(true-breeding
parents)
F1 Generation
(hybrids)

Purple
flowers
White
flowers
All plants had
purple flowers
F2 Generation
705 purple-flowered
plants
224 white-flowered
plants
Table 14-1
Fig. 14-4
Allele for purple flowers
Locus for flower-color gene
Allele for white flowers
Homologous
pair of
chromosomes
Fig. 14-5-3
P Generation
Purple flowers
Appearance:
Genetic makeup:
PP
Gametes:
White flowers
pp
p
P
F1 Generation
Appearance:
Genetic makeup:
Purple flowers
Pp
1/
2
Gametes:
1/
2
P
Sperm
F2 Generation
P
p
PP
Pp
Pp
pp
P
Eggs
p
3
1
p
Fig. 14-6
3
Phenotype
Genotype
Purple
PP
(homozygous)
Purple
Pp
(heterozygous)
1
2
1
Purple
Pp
(heterozygous)
White
pp
(homozygous)
Ratio 3:1
Ratio 1:2:1
1
Fig. 14-7
TECHNIQUE

Dominant phenotype, Recessive phenotype,
unknown genotype:
known genotype:
PP or Pp?
pp
Predictions
If PP
Sperm
p
p
P
Pp
Eggs
If Pp
Sperm
p
p
or
P
Pp
Eggs
P
Pp
Pp
pp
pp
p
Pp
Pp
RESULTS
or
All offspring purple
1/2
offspring purple and
1/2 offspring white
The Law of Independent Assortment
• Mendel derived the law of segregation by following
a single character
• The F1 offspring produced in this cross were
monohybrids, individuals that are heterozygous for
one character
• A cross between such heterozygotes is called a
monohybrid cross
Copyright © 2008 Pearson Education Inc., publishing as Pearson Benjamin Cummings
Fig. 14-8
EXPERIMENT
YYRR
P Generation
yyrr
Gametes YR

F1 Generation
yr
YyRr
Hypothesis of
dependent
assortment
Predictions
Hypothesis of
independent
assortment
Sperm
or
Predicted
offspring of
F2 generation
1/
4
Sperm
1/ YR 1/
2
2 yr
1/
4
1/
2
YR
1/
4
Yr
1/
4
yR
1/
4
yr
YR
YYRR YYRr
YyRR
YyRr
YYRr
YYrr
YyRr
Yyrr
YyRR
YyRr
yyRR
yyRr
YyRr
Yyrr
yyRr
yyrr
YR
YYRR
Eggs
1/
2
YyRr
1/
4
Yr
Eggs
yr
YyRr
3/
4
yyrr
1/
4
yR
1/
4
Phenotypic ratio 3:1
1/
4
yr
9/
16
3/
16
3/
16
1/
16
Phenotypic ratio 9:3:3:1
RESULTS
315
108
101
32
Phenotypic ratio approximately 9:3:3:1
Fig. 14-8a
EXPERIMENT
YYRR
P Generation
yyrr
Gametes YR

F1 Generation
yr
YyRr
Hypothesis of
independent
assortment
Hypothesis of
dependent
assortment
Predictions
Sperm
or
Predicted
offspring of
F2 generation
1/
4
Sperm
1/
2
YR
1/
2
1/
4
Yr
yR
1/
4
yr
YR
YYRR YYRr
YyRR
YyRr
YYRr
YYrr
YyRr
Yyrr
YyRR
YyRr
yyRR
yyRr
YyRr
Yyrr
yyRr
yyrr
YR
YYRR
Eggs
1/
2
1/
4
yr
1/
4
1/
2
YR
YyRr
1/
4
Yr
Eggs
yr
yyrr
YyRr
3/
4
1/
4
yR
1/
4
Phenotypic ratio 3:1
1/
4
yr
9/
16
3/
16
3/
16
1/
16
Phenotypic ratio 9:3:3:1
Fig. 14-8b
RESULTS
315
108
101
32
Phenotypic ratio approximately 9:3:3:1
• Using a dihybrid cross, Mendel developed the law of
independent assortment
• The law of independent assortment states that each pair of alleles
segregates independently of each other pair of alleles during
gamete formation
• Strictly speaking, this law applies only to genes on different,
nonhomologous chromosomes – not to linked genes – gene on
same chromosome
• Genes located near each other on the same chromosome tend to
be inherited together
Copyright © 2008 Pearson Education Inc., publishing as Pearson Benjamin Cummings
Extending Mendelian Genetics for a
Single
Gene
• Inheritance of characters by a single gene may
deviate from simple Mendelian patterns in the
following situations:
– When alleles are not completely dominant or
recessive
– When a gene has more than two alleles
– When a gene produces multiple phenotypes
Copyright © 2008 Pearson Education Inc., publishing as Pearson Benjamin Cummings
Degrees of Dominance
• Complete dominance occurs when phenotypes of
the heterozygote and dominant homozygote are
identical
• In incomplete dominance, the phenotype of F1
hybrids is somewhere between the phenotypes of
the two parental varieties
• In codominance, two dominant alleles affect the
phenotype in separate, distinguishable ways
Copyright © 2008 Pearson Education Inc., publishing as Pearson Benjamin Cummings
Fig. 14-10-3
P Generation
Red
CRCR
White
CWCW
CR
Gametes
CW
Pink
CRCW
F1 Generation
Gametes 1/2 CR
1/
CW
2
Sperm
1/
2
CR
1/
2
CW
F2 Generation
1/
2
CR
Eggs
1/
2
CRCR
CRCW
CRCW
CWCW
CW
Inheritance of Sex-Linked Genes
• The sex chromosomes have genes for many
characters unrelated to sex
• A gene located on either sex chromosome is called
a sex-linked gene
• In humans, sex-linked usually refers to a gene on
the larger X chromosome
Copyright © 2008 Pearson Education Inc., publishing as Pearson Benjamin Cummings
• Sex-linked genes follow specific patterns of
inheritance
• For a recessive sex-linked trait to be expressed
– A female needs two copies of the allele
– A male needs only one copy of the allele
• Sex-linked recessive disorders are much more
common in males than in females
Copyright © 2008 Pearson Education Inc., publishing as Pearson Benjamin Cummings
Fig. 15-7
XNXN
Sperm Xn

XnY
Sperm XN
Y
Eggs XN
X N X n X NY
XN
X NXn XNY
(a)
XNXn

XNY
XNXn
Sperm Xn
Y

XnY
Y
Eggs XN XNXN XNY
Eggs XN
X NX n X NY
XnXN XnY
Xn
XnXn XnY
Xn
(b)
(c)
Fig. 14-11
Allele
IA
IB
Carbohydrate
A
B
i
none
(a) The three alleles for the ABO blood groups
and their associated carbohydrates
Genotype
Red blood cell
appearance
Phenotype
(blood group)
IAIA or IA i
A
IBIB or IB i
B
IAIB
AB
ii
O
(b) Blood group genotypes and phenotypes
•Rh factor is a protein called an antigen on RBC
•An antigen is any substance that the body considers "foreign" and
thus stimulates the body to produce antibodies against it.
•Rh factor, like the blood types A, B, and O, is inherited from one's
parents.
•A simple blood test can determine blood type, including the
presence of the Rh factor.
•About 85 percent of white Americans and 95 percent of African
Americans have the Rh factor and are known as Rh-positive.
•Those without the Rh factor are Rh-negative.
Extending Mendelian Genetics for
Two
or
More
Genes
• Some traits may be determined by two or more
genes
Copyright © 2008 Pearson Education Inc., publishing as Pearson Benjamin Cummings
Polygenic Inheritance
• Quantitative characters are those that vary in the
population along a continuum
• Quantitative variation usually indicates polygenic
inheritance, an additive effect of two or more
genes on a single phenotype
• Skin color in humans is an example of polygenic
inheritance
Copyright © 2008 Pearson Education Inc., publishing as Pearson Benjamin Cummings
Fig. 14-13

AaBbCc
AaBbCc
Sperm
1/
Eggs
1/
8
1/
8
1/
8
1/
8
1/
1/
8
1/
1/
8
8
1/
8
1/
64
15/
8
1/
1/
8
8
8
1/
8
1/
8
1/
8
8
1/
Phenotypes:
64
Number of
dark-skin alleles: 0
6/
64
1
15/
64
2
20/
3
64
4
6/
64
5
1/
64
6
DNA – A Historical Perspective
• 1865 – Gregor Mendel – “Father of Heredity”
• 1869 – Johann Miescher (Swiss biochemist) – isolates DNA from WBC
• 1902 – Walter Sutton – American Geneticist – Columbia U. Theory of the
Chromosome
• 1928 – Frederick Griffith – British Bacteriologist – discovers transformational
factor
• 1944 – Oswald Avery et al. - Canadian-born American physician – shows that
the transformational factor was not a protein but DNA
• 1952 – Alfred Hershey & Martha Chase – provide conclusive evidence that
DNA is the transformational factor
• 1952 – Rosalind Franklin & Maurice Wilkins – use x-ray diffraction to analyze
DNA
• 1953 – James Watson & Francis Crick construct double helix model of DNA
Fig. 16-6
(a)
(b)
Fig. 16-8
Fig. 16-5
Sugar–phosphate
backbone
5 end
Carbon 1 –
bonds to
nitrogen base
Nitrogenous
bases
Purines
Thymine (T)
Pyrimidines
Carbon 3 –
bonds to next
nucleotide
Adenine (A)
Carbon 5 –
bonds to
phosphate group
Cytosine (C)
DNA nucleotide
Phosphate
Sugar (deoxyribose)
3 end
Guanine (G)
#1.
TECHNIQUE
5 µm
#2
Key
Maternal set of
chromosomes
Paternal set of
chromosomes
Two sister chromatids
of one replicated
chromosome
Two nonsister
chromatids in
a homologous pair
Centromere
Pair of homologous
chromosomes
(one from each set)
#3
Key
Haploid gametes (n = 23)
Haploid (n)
Egg (n)
Diploid (2n)
Sperm (n)
C.
A.
D.
B.
E.
Mitosis and
development
Multicellular diploid
adults (2n = 46)
Prophase I
Metaphase I
C.
Anaphase I
Sister chromatids
remain attached
B
Homologous
chromosomes
separate
Homologous
chromosomes
Fragments
of nuclear
envelope
Microtubule
attached to
kinetochore
D
#5
A.
B.
#6
SUMMARY
Property
Mitosis
Meiosis
DNA
replication
A. When does this happen???
Occurs during interphase before meiosis I begins
Number of
divisions
One, including prophase, metaphase,
anaphase, and telophase
B. How many divisions??
Pairing of
homologous
chromosomes
Does not occur
C. Exactly when does this occur?
Number of
daughter cells
and genetic
composition
Two, each diploid (2n) and genetically
identical to the parent cell
D. # of daughter cells??
Role in the
animal body
Enables multicellular adult to arise from
zygote; produces cells for growth, repair,
and, in some species, asexual reproduction
Produces gametes; reduces number of chromosomes by half
and introduces genetic variability among the gametes
7.
Possibility 2
Possibility 1
Two equally probable
arrangements of
chromosomes at
metaphase I
Metaphase II
Daughter
cells
Combination 1 Combination 2
Combination 3 Combination 4
#8. Enzymes involved in DNA Replication
& Transcription
Enzyme
Function
A.
“molecular zipper” – unwinds double helix;
breaks hydrogen bonds that holds base pairs
together
B.
“molecular swivel”- relieves overwinding
stress on DNA strands by working ahead of
helicase and breaking, swiveling and rejoining
small sections of the DNA molecule
C.
Using a parent DNA strand, adds free-floating
nucleotides (A, T, G, & C’s) covalently to the
new strand being constructed.
D.
“molecular glue” – joins fragments of the
New DNA strand together
E.
Uses one strand of DNA as a template to
construct mRNA – adds free-floating
nucleotide
F.
Fixes mistakes on DNA molecule
There are several different mechanisms (or modes) of
natural selection that involve changes in niches.
These mechanisms include directional selection,
disruptive selection, and stabilizing selection.
State which of these is involved in each of the following
examples and predict the change (if any)
produced by each.
a.Most giraffes in an area are the same height. Adult
giraffes much taller or shorter than this height are
unusual. The type and typical height of the
vegetation does not change.
In an area, some chipmunks have lightcolored fur and some have dark fur, but
the largest number have medium-colored
fur. The ground is usually a mediumbrown color in winter, however, the
climate drastically changes, and snow
becomes unusually frequent and heavy.
Most grasshoppers in an area are
medium-green in color. There are a
smaller number of them that are light
green and some are brownish. A
predator is introduced into the area and
it has a preference for medium-green
grasshoppers.