Opening Assignment Day 1
 Get a pen or pencil out to take a pretest on the
material we will learn this week.
Unit6: Reproduction,
Cell Division, Genetics, DNA &
Protein Synthesis
BY MRS. SHAW
6 Characteristics of ALL Living things
Made of
cells
Respond
to stimuli
Grow and
develop
Life
Need
energy
Evolve
Reproduce
6 Characteristics of ALL Living things
 Made of cells
 Reproduce
 Grow and Develop
 Respond to stimuli
 Need energy
 Evolve
Sun – Producers – Consumers - Decomposers
Why is reproduction required for the survival
of a species?
 Every living thing has a
lifespan – a beginning and an
end.
 If species could not reproduce
they would die off or
become extinct.
 Reproduction of species
also allows for variations to
occur so that organisms can
adapt to changes in their
environment.
Sexual vs. Asexual
Reproduction
Sexual Reproduction
 Involves two parent sex
Pollination
cells that combine to
create a zygote.
 Each parent cell adds
50% of the genetic
material to the
offspring.
 Each offspring is
genetically unique –
except for with identical
twins
Fertilization
Sexual Reproduction continued
Advantages
Disadvantages
 Genetic Variation!!!
 Takes more energy and
time.
 Requires two parents.
Asexual Reproduction
 Involves one parent
cell that divides to create
a two new daughter
cells.
 Each offspring is
genetically identical
to the parent cell.
Asexual Reproduction continued
Advantages
Disadvantages
 Faster
 No genetic variation!!
 Only requires one
parent, so less energy
needed
Asexual vs. Sexual Reproduction overview
SEXUAL
ASEXUAL
2
1
DNA of offspring:
unique or identical
Unique DNA
Identical DNA
Advantages
Genetic Diversity which
leads to increase in
chance of survival
Faster and requires less
energy
Disadvantages
Takes more time
and energy
No genetic diversity
Parents needed
Types of Asexual Reproduction
 Binary Fission: one cell
divides to make two cells
found in single celled
organisms. (prokaryotes)
 Budding: an offspring
grows out of the body of
the parent.
 Spore: a reproductive cell
capable of developing into
a new individual if
environmental conditions
are right.
Types of Asexual Reproduction continued
 Vegetative Reproduction:
Production of a new plant
from a stem or branch.
 Regeneration: piece of a
parent is detached then
grows into a new individual.
 Fragmentation: An
organism breaks up into two
or more pieces or fragments.
The fragments then grow
into new organisms.
Mitosis vs. Meiosis
MITOSIS = BODY CELLS
 Used in growth and repair
MEIOSIS = SEX CELLS
 ONLY used to create sex
cells
 Type of asexual
reproduction
 One parent cell divides to
make two identical
daughter cells with a full
set of chromosomes
(diploid)
 NOT the same as sexual
reproduction
 One parent cell divides to
make four daughter cells
with a half set of
chromosomes (haploid)
Mitosis vs. Meiosis
Meiosis vs. Mitosis overview
MEIOSIS
Starts with
MITOSIS
One diploid cell – one cell One diploid cell – one cell
with a full set of
with a full set of
chromosomes
chromosomes
Cell divisions in
process
2
1
Daughter cells
produced
4
2
Chromosomes in
daughter cells
Haploid – half set
Diploid – full set
production of sex cells –
egg or sperm
production of body cells
for growth and repair
Main Use
Opening Assignment Day 2
Create a venn diagram to compare and contrast
sexual and asexual reproduction.
Sexual
Asexual
Practice Question
Some organisms are capable of reproducing
asexually through processes such as budding or
parthenogenesis. What is an advantage of asexual
production for an organism?
A. It allows organisms to increase population rapidly.
B. It allows haploid cells to unite to produce a zygote.
C. It allows for greater genetic diversity within a species.
D. It allows crossing over to take place during replication.
Practice Problem
Sponges are important in aquatic ecology and they are capable of
reproducing both sexually and asexually. What is an advantage to
a species, such as the sponge, of being able to reproduce sexually?
A. Sexual reproduction increases genetic variation within a
species.
B. Sexual reproduction produces offspring that are genetically
identical to the parents.
C, Sexual reproduction allows the zygote to have twice the
number of chromosomes of the parent.
D. Sexual reproduction produces a genetically improved zygote
from the mutation of the parents' haploid gametes. Bottom of
Form
Mitosis
 Remember that Mitosis is a type of asexual
reproduction.
 Mitosis vocabulary:
 Interphase: the phase before mitosis begins when the DNA is
being replicated.
 Centromeres: the part of a chromosome that links sister
chromatids
 Cytokinesis: the separation of the daughter cells
Vocabulary
Chromatin: a loose mass of
genetic material composed of DNA
and proteins
Chromosomes: condensed form
of DNA wrapped around proteins
Chromatid: Chromatid is the
daughter strand of a duplicated
chromosome that is joined by a
single centromere.
Stages of Mitosis
PMAT
 Prophase: Chromatin
condenses into
chromosomes. Nuclear
envelope disappears.
 Metaphase:
Chromosomes align at
the equatorial plate
 Anaphase: Sister
chromatids separate,
centromeres divide
 Telophase: Chromatin
expands and cytoplasm
divides
Stages of Meiosis
 Meiosis has similar
phases as mitosis with
some exceptions
 Crossing over occurs in
Prophase 1 of Meiosis
 Cells divide twice
through 8 phases and the
process results in 4
haploid daughter cells
 Meiosis ONLY happens
to produce sex cells
(gametes)
Meiosis: Crossing Over
 In prophase I of meiosis, the
replicated homologous pair of
chromosomes comes together in
the process called synapsis, and
sections of the chromosomes are
exchanged.
 You can see that after crossing
over, the resultant chromosomes
are neither entirely maternal nor
entirely paternal, but contain
genes from both parents.
 Synapsis and crossing over occur
only in meiosis.
Video explanations
 http://highered.mcgraw-
hill.com/sites/0072495855/student_view0/chapter
2/animation__comparison_of_meiosis_and_mitosi
s__quiz_1_.html
 Then show “Unique features of Meiosis”.
Practice Problem
Mitosis and meiosis are processes that occur in an
organism during reproduction. Which of the
following is a result of mitosis?
A. two identical daughter cells
B. four haploid cells that have genetic variation
C. uncontrolled cell division in the form of cancer
cells
D. a single diploid cell that is genetically identical to
the parent cell
Practice Problem
Mitosis and meiosis are both processes involved in
reproduction. Which statement correctly compares
mitosis and meiosis?
A. Mitosis and meiosis both produce genetic variation within their
daughter cells.
B. Mitosis results in the production of two genetically identical diploid
cells and meiosis produces four haploid cells.
C. Mitosis and meiosis are both divided into only four distinct phases:
prophase, metaphase, anaphase, and interphase.
D. Mitosis results in the production of two genetically identical diploid
cells and meiosis produces four genetically identical haploid cells.
What happens when cells continue to divide?
 http://www.youtube.com/watch?v=lpAa4TWjHQ4
Opening Assignment Day 3
Create a venn diagram to compare and contrast
mitosis and meiosis – use your notes from the last 2
days
Mitosis
Meiosis
Practice Problem
A scientist is developing a potential treatment for cancer. She grows cells in
hundreds of petri dishes and exposes the dishes to environments that are
known to cause cancer. After exposure, the scientist determines that some of the
petri dishes have cancer cells.
What factor do all the petri dishes that contain cancer cells have in common?
A.
All the petri dishes with cancer cells have a disrupted cell cycle.
B.
All the petri dishes with cancer cells have been exposed to tobacco smoke.
C.
All the petri dishes with cancer cells could be treated successfully if they receive the
same treatment.
D.
All the petri dishes with cancer cells have genetically identical cells that make them
susceptible to cancer.
Practice Problem
If an experimental drug aims to prevent and inhibit the multiplication of
cancer cells, which of the following would be the best approach for scientists
to take in developing the anticancer drug?
A. The drug should focus on stimulating weakened cells to grow and divide.
B. The drug should prevent meiosis, but also increase mitosis in the cancer
cells.
C. The drug should stimulate the cells to continue to divide, but at an
increased rate.
D. The drug should interrupt the cell cycle and prevent cell division in the
cancer cells Bottom of Form
Reproductive System
The reproductive system is a collection
of organs that work together for the
purpose of producing a new life.
The major organs of the reproductive
system include the external genitalia
and internal organs, including gonads
that produce gamete, which is a cell
that fuses with another cell during
conception in organisms that reproduce
sexually..
The Endocrine system works with the
Reproductive system to produce
hormones, chemical messengers, that
help regulate most normal body
functions.
Sex & Growth Hormones
 Large scale body
changes

how do they work
turn genes on
 start new processes in
the body by turning
genes on that were lying
“dormant”

Reproductive hormones
Pineal gland
 Testosterone
from testes
 sperm production & secondary
sexual characteristics
 Estrogen
 from ovaries
 egg production, preparing
uterus for fertilized egg &
secondary sexual
characteristics

BOTH SEXES HAVE BOTH
HORMONES just in different
amounts. Males have more
testosterone than estrogen and
females have more estrogen than
testosterone
Male
reproductive
system
 Sperm production happens in the Testes
 over 100 million produced per day!
 ~2.5 million released per drop!
Male reproductive system
 Testes & epididymis
 sperm production &
maturation
 Glands
 seminal vesicles,
prostate, bulbourethal
 produce seminal fluid

nutrient-rich
Male reproductive system
 Testicles

produces sperm & hormones
 Scrotum

sac that holds testicles outside of body
 Epididymis

where sperm mature
 Vas deferens

tubes for sperm to travel from testes to penis
 Prostate, seminal vesicles,
Cowper’s (bulbourethal) glands

nutrient rich fluid to feed & protect sperm
Spermatozoa are male gametes, which contain haploid
DNA. Where are spermatozoa produced?
ovaries
penis
prostate
testes
Spermatogenesis is the process by which sperm develop
and mature. Which of the following sequences correctly
describes the anatomical path of spermatozoa from
formation to ejaculation?
testes, vas deferens, prostate, urethra
testes, urethra, prostate, vas deferens
prostate, vas deferens, testes, urethra
prostate, urethra, testes, vas deferens
Sperm cells are mobile and must travel through the
female reproductive tract to fertilize an egg. Which of the
following structures enables sperm cells to swim?
A. cilia
B. flagella
C. pseudopods
D. ribosomes
Which of the following is NOT a structure of the male
reproductive system?
A.
fallopian tubes
B.
seminal vesicles
C.
urethra
D.
vas deferens
Female reproductive system
Female reproductive system
 Ovaries

produces eggs & hormones
 Uterus

nurtures fetus; lining builds up each month
 Fallopian tubes

tubes for eggs to travel from ovaries to uterus
 Cervix

opening to uterus, dilates 10 cm for birthing baby
 Vagina

birth canal for birthing baby
Female reproductive system
Female hormones
 FSH & LH
 released from pituitary
 stimulates egg development & hormone release
 peak release = release of egg (ovulation)
 Estrogen
 released from ovary cells around developing egg
 stimulates growth of lining of uterus
 decreasing levels causes menstruation
 Progesterone
 released from “corpus luteum” in ovaries
 cells that used to take care of developing egg
 stimulates blood supply to lining of uterus
 decreasing levels causes menstruation
Which of the following statements about reproductive hormones is TRUE?
A. Only women produce progesterone.
B. Estrogen levels are highest during early pregnancy.
C. Reproductive hormones affect only the reproductive system.
D. Men and women produce both estrogen and testosterone.
In the male reproductive system, gametes are produced in the testicles.
Which of the following structures of the female reproductive system has the
same function as the testicles?
A. cervix
B. uterus
C. fallopian tubes
D. ovaries
Fertilization
Fertilization is when the
sperm becomes implanted
into the egg, this happens
in the fallopian tube.
Fertilization results in the
formation of a zygote.
The zygote starts
performing mitosis to grow
and eventually forms a
blastocyst.
The Blastocyst implants in
the uterus where it will get
the nourishment it needs to
continue maturing and
growing.
Placenta
 Food & gases diffuse across blood vessels
How does a Fetus develop?
 Brain and spinal cord start to form first but continue






developing throughout pregnancy (1st 5 weeks)
Then heart forms and starts beating (week 6)
Liver, kidneys, intestines, eyes, and nasal cavities (week 68) (ADD THIS TO NOTES: Week 8 is when the embryo
stage ends and the fetal stage begins.
Limbs and lymphatic system form around week 8
By week 9 most essential organs have begun to develop.
Facial features and teeth form by week 12.
After this every organ and system continue to mature and
develop.
Which of the following sequences correctly describes prenatal
development?
A. blastocyst implants in uterus, zygote forms, heart begins beating, lungs
can breathe air, sex organs become visible
B. blastocyst implants in the uterus, zygote forms, heart begins beating,
sex organs become visible, lungs can breathe air
C. zygote forms, blastocyst implants in the uterus, heart begins beating,
sex organs become visible, lungs can breathe air
D. zygote forms, blastocyst implants in the uterus, sex organs become
visible, heart begins beating, lungs can breathe air Bottom of Form
Which of the following correctly describes the function of
amniotic fluid as it relates to the development of a human
fetus?
A. It provides protection and moisture for the fetus.
B. It carries blood between the fetus and the mother.
C. It is where the first fetal blood cells originate.
D. It provides nutrition and oxygen for the fetus. Bottom
of Form
A normal human gestational period lasts forty weeks. Which of the
following explains why the eighth week of gestation is notable?
A. The gender of the fetus can be determined.
B. The embryo is approximately the size of a lime.
C. The embryo stage ends and the fetal stage begins.
D. Most organ systems are developed and functional.
Human fetal development
4 weeks
7 weeks
Human fetal development
10 weeks
Human fetal development
12 weeks
20 weeks
Human fetal development
 The fetus just spends much of the 2nd & 3rd
trimesters just growing
…and doing various flip-turns & kicks inside
amniotic fluid
Week 20
Human fetal development
 24 weeks (6 months; 2nd trimester)
fetus is covered with
fine, downy hair
called lanugo. Its skin
is protected by a
waxy material called
vernix
Getting crowded in there!!
 32 weeks (8 months)
The fetus sleeps 9095% of the day &
sometimes
experiences REM
sleep, an indication
of dreaming
Birth (36 weeks)
Intestine
Placenta
Umbilical
cord
Wall of
uterus
Bladder
Cervix
Vagina
Practice question
Folate is a crucial vitamin for proper development of the neural
tube, which eventually becomes the brain and spinal cord. Which of
the following might explain why neural tube defects occur more
frequently than other types of birth defects?
A. Folate is rarely found in common foods and must be
supplemented.
B. Since the nervous system forms so late, defects go undetected by
early ultrasounds.
C. The neural tube forms in the first three weeks, before most
women know they are pregnant.
D. The first and second trimesters of pregnancy use most of the
mother's folate supply, leaving a limited amount for neural tube
formation. Bottom of Form
Fetal Development
 Life’s Greatest Miracle
 http://www.youtube.com/watch?v=1w9o89KkX2A
 Skip to 7 min.
Sample Item 16 SC.912.L.16.17
Mitosis and meiosis are processes involved in cellular
reproduction. Which of the following describes an
event that results from mitosis but NOT
meiosis?
A. two stages of cell division
B. replication of cellular genetic material
C. daughter cells that are identical to the
parent cell
D. four daughter cells that are produced from
each parent cell
Sample Item 15 SC.912.L.16.13
A fertilized egg undergoes several stages before it is
successfully implanted. The diagram below shows
these stages as the fertilized egg travels through the
female human reproductive system.
In which of the following structures of the female
human reproductive system is the blastocyst
implanted during normal human development?
A. ovary
B. uterus
C. vagina
D. amniotic sac
Opening Assignment – Let’s see what you already know 
Copy and match the definitions on the left with the terms on the right.
___ 1. genotypes made of the same alleles
A. alleles
____ 2. different forms of genes for a single trait
____ 3. gene that is always expressed
____ 4. gene that is expressed only in the
homozygous state
____ 5. genotypes made of two different alleles
____ 6. the genetic formula for a trait
____ 7. the physical manifestation of a genotype
B. Phenotype
C. genotype
D. homozygous
E. recessive
F. heterozygous
G. Dominant
8. Which ones are dominant alleles? D e k L N n R S
9. Which ones are recessive alleles? M n d F G r k P
More review practice
Which combinations are . . . . . .
10. Homozygous dominant?
AA
Gg KK mm uu
Rr
TT
11. Homozygous recessive
ee
Ff
HH Oo qq
Uu ww
12. Genotypes in which dominant gene must show
AA
Dd EE ff
Jj
RR
Ss
13. Genotypes in which recessive gene must show
aa
Gg Ff
KK rr
Oo Tt
Part 2: Genetics – Punnett
Squares and Pedigrees
How are Heredity and Genetics related?
 Heredity :
the passing of traits
from parent to offspring
 Traits are controlled by
Genes.
 A Gene is a section on a
chromosome that has
genetic information for
ONE trait.
How are
Heredity and
Genetics
related?
SO what is GENETICS?
Genetics: The study of how traits are
inherited.
Gregor Mendel – the Father of Genetics
o First known geneticist and
“father of genetics”
o Was an Austrian monk
and was born in 1822
o Did most of his genetic
studies on pea plants
What did Mendel learn and how did
he learn it?
 He learned that when he
self pollinated a purple
flowered pea plant all the
offspring had purple
flowers.
X
=
X
=
 The same thing
happened when he self
pollinated a white flower
plant – all the offspring
were white.
What did Mendel learn and how did
he learn it?
 So, next he cross
pollinated a purple and
white flower plant.
 All the offspring turned
out purple.
 This led him to believe
that purple was a
dominant trait over
white for these plants.
What did Mendel learn and how did
he learn it?
 Next, he self pollinated
the “hybrid” purple
flower plant and what he
found was that about
25% of the time the
flowers produced were
WHITE!
Mendel’s Conclusions
1. He concluded that 2
genetic factors control
each inherited trait.
2. He also proposed that
when organisms
reproduce, each
reproductive cell
contributes one factor
for each trait.
What are ALLELES?
o Alleles are ONE FORM of a gene (there can be
more than one form)
o
Sex cells have one form of a gene on their chromosomes
o Body cells have two forms or ALLELES for a single
gene (you got one from Mom and one from Dad)
o One may be dominant over another. If this happens, the
dominant gene is the one expressed. If not, the recessive
trait is expressed.
Dominant vs. Recessive
Dominant traits
Recessive traits
 An allele that blocks
 An allele that is
another allele.
 Usually expressed
using a CAPITAL letter
 P = purple flower
P X p = Pp Purple Hybrid
blocked by another
allele.
 Usually expressed
using a LOWERCASE
letter
 p = white flower
Genotype vs. Phenotype
 Genotype is the
genetic formula of
the two alleles that
control the expression of
the trait.
 Pp = the genotype of
our offspring
 Phenotype is the
physical appearance
of the genotype.
 Purple flowers is the
phenotype of the
offspring.
Homozygous vs. Heterozygous
 Homo means SAME
 Hetero means DIFFERENT
 Homozygous means 2
 Heterozygous means 2
of the same alleles
 Two dominant capitals or
two recessive lowercase:
PP or pp
different alleles
 One dominant capital
letter and one recessive
lowercase letter: Pp
More Important Vocabulary
 P1 = Parent generation
 F1 = daughter generation or 1st generation of
offspring from the P1 generation
 F2 = daughter generation from the offspring of the
F1 generation.
Punnett
Squares
A model used to
predict possible
genotypes and
phenotypes of
offspring.
P1= AA & aa
F1= 100% Aa (genotype)
100% Red feathers
(phenotype)
Mom’s genotype
Dad’s genotype
What will all the offspring look like
(phenotype)?
 In guinea pigs, short hair, S, is
Let’s Practice
Complete the following
Punnett squares
dominant to long hair, s.
a. One guinea pig is Ss and one is
ss.
according to the
directions given. Then,
fill in the blanks beside
each Punnett square
with the correct
numbers.
Expected genotype and phenotype
possibilities:
Genotypes: ________________
Phenotypes:________________
 In guinea pigs, short hair, S, is
Let’s Practice
Complete the following
Punnett squares
dominant to long hair, s.
b. Both guinea pigs are
heterozygous for short hair.
according to the
directions given. Then,
fill in the blanks beside
each Punnett square
with the correct
numbers.
Expected genotype and phenotype possibilities:
Genotypes: ________________
Phenotypes:________________
 In rabbits, brown fur (F) is
Opening
Assignment
Get your
homework out
then do the
Punnett
square
problem to the
right
dominant over white fur (f).
 A heterozygous brown fur rabbit
is crossed with a homozygous
white fur rabbit.
 Draw a punnett square and
determine the genotypes and
phenotypes of the possible
offspring.
Practice 
1. B= Brown eyes b= blue eyes Mom= Bb Dad= BB
What are the eye color possibilities if they chose to have
children?
Genotypes
Phenotypes
More practice 
1. Curly hair is recessive, and straight hair is dominant. A
woman with curly hair marries a man who is homozygous
dominant for straight hair. Predict the outcomes for their
children.
Genotypes
Phenotypes
Other Patterns of Inheritance
 Incomplete dominance: when one allele is
not completely dominant over another and
their expression (phenotype) is a mixture of
the two.

Example: A black mouse is crossed with a white
mouse and the offspring have grey fur.
Codominance– existing together. Both
alleles are expressed.
Example: When you cross a black cat with a brown
cat their kittens may have black fur with white spots.
Other Patterns of Inheritance cont.
 Multiple alleles: A gene with more than two
alleles. Many genes exist this way.

For example: A rabbits coat color is determined by a
single gene that has at least four different alleles.
Other Patterns of Inheritance cont.
 Polygenic -0 when traits are controlled by
two or more genes.

For example: Human skin color is made from a
combination of many genes.
Other Patterns of Inheritance cont.
 Sex linked inheritance: The inheritance of a
trait (phenotype) that is determined by a
gene located on one of the sex chromosomes
Some diseases or traits are
found on the X or Y
chromosome only. So since
the male is the only one with a
Y chromosome, he is the only
one able to give the diseases
found on the Y and he will only
be able to give it to his male
offspring. (because if he has a
daughter than he has given his
X chromosomes and)
Sex linked traits
 http://www.khanacademy.org/science/biology/here
dity-and-genetics/v/sex-linked-traits
Sample Item 12 SC.912.L.16.2
Hemophilia is a sex-linked, recessive trait. Which of the
following describes the probability of hemophilia in
the offspring of a man who does not have hemophilia
and a woman who is a heterozygous carrier?
A. There is a 25% chance that their sons will have hemophilia.
B. There is a 100% chance that their sons will have hemophilia.
C. There is a 0% chance that their daughters will have
hemophilia.
D. There is a 50% chance that their daughters will have
hemophilia.
Opening Assignment
Copy and match the term
with the correct definition
1. Polygenic inheritance
2. Codominance
3. Sex linked Inheritance
4. Incomplete dominance
A. When both alleles are
expressed as a mixture
B. When both alleles share
dominance and are each
expressed
C. When a trait is
controlled by more than
one gene
D. When a genetic trait is
found on either the X or Y
chromosome
Draw a
Punnett
square to
figure it out
A hairline that comes to a point in the center of
the forehead is called a widow's peak. Having a
widow's peak is a dominant trait, while having
a straight hairline is a recessive trait. Cate, a
woman with a widow's peak, has two children
with James, a man with a straight hairline like
her father.
What is the probability that their next child
will have a straight hairline?
A.
B.
C.
D.
0%
25%
50%
75%
Four major blood phenotypes (A, B, AB, and O) are
determined by three alleles: A, B, and O. A person
with type A has a certain protein on their blood cells'
membranes. A person with type B has a different
protein appearing on their cells' membranes. Cells
from type AB have both proteins, but cells from type
O, which is recessive, has neither protein.
This example illustrates which of the following
phenomena?
A. codominance
B. complete dominance
C. partial dominance
D. polygenic inheritance
Pedigrees
A pedigree
shows
phenotypes of
genetically
related family
members and
can also be used
to help
determine
genotypes.
Add this to your notes 
Draw a Punnett
square to figure
it out
Colorblindness is a recessive, sex-linked
trait located on the X chromosome.
Gaspar is a colorblind man, and his wife
Stephanie is a carrier for colorblindness.
If they have a male child, what is the
probability that their son will be
colorblind?
A.
B.
C.
D.
0%
25%
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What are the
possible
parent
options?
There are three alleles for blood type: A, B
and O. Types A and B are co-dominant,
and O is recessive. Based on phenotypes
in the pedigree chart below, what is the
genotype of the father, Ricky?
A. AA
B. AO
C. AB
D. OO
Dihybrid
Crosses:
While a
MONOHYBRID
CROSS (Ee X EE)
shows the
probabilities of
what happens
when one trait is
crossed, a
DIHYBRID
CROSS shows
what happens
when two traits
are crossed.
 Dihybrid crosses = crossing 2
traits, fur color and tail length, in
a hamster
 E= brown fur e= white fur
 F = long tail
f = short tail
EeFF x eeFf
Add this to your notes 
Draw a
dihybrid
Punnett square
to figure it out
A goat that is heterozygous for long
hair (Hh) and curved horns (Cc)
mates with a goat that is
homozygous for short hair (hh)
and straight horns (cc). Which of
the following genotypes is
impossible for their offspring to
have?
A. HhCc
B. HHCc
C. hhCc
D. hhcc
FCAT EXPLORER is due 4/25 !!
Remember this program equals
3 separate quiz grades for this
semester!!
START OVER SPRING
BREAK!!!!
Fetal Development
 Life’s Greatest Miracle
 http://www.youtube.com/watch?v=1w9o89KkX2A
 Skip to 26.45 min.
Opening Assignment
 Get a pencil out and ready to take a pretest on Part 3
– DNA, RNA & Protein Synthesis.
Part 3: DNA
What is DNA?
 DNA or
Deoxyribonucleic acid is
a type of molecule that
determines the traits that
an individual inherits
 It is the blueprint of
instructions on how to
create proteins and every
type of cell in your body.
Where is DNA located?
In Prokaryotes
In Eukaryotes
 In Prokaryotes the DNA is
•In Eukaryotes the DNA is
located in the nucleus of
the cell in the
chromosomes.
loosely coiled in the
cytoplasm.
DNA
Structure
Function
 Nucleotide: a molecule
 DNA’s main function is
that consists of a sugar,
a phosphate, and a
base.
 Bases: adenine,
thymine, guanine,
cytosine
 Double helix structure
to provide the
instructions for
creating proteins.
 Proteins are the
chemicals that aid in
cellular processes.
DNA Replication
Transcription
Translation
 The process of making
 The process of making
mRNA from DNA.
 Remember mRNA
takes the instructions
for making a necessary
protein to the
ribosome.
a protein from RNA.
 This happens in the
ribosome.
What are Chromosomes?
Chromosomes are strands of DNA
coiled around proteins.
Genes, Alleles, Chromosomes & DNA . . . .
 How are these terms related?
 Alleles are singular forms of a gene. (single letter B or b)
 Genes have two alleles . . . one from each parent. (BB, Bb, or bb)
 Genes are sections of DNA that provide the instructions for a
specific trait.
 Chromosomes are coils of DNA wrapped around proteins, located
in the nucleus of eukaryotic cells.
Transcription vs. Translation
 https://www.youtube.com/watch?v=h3b9ArupXZg
Opening Assignment
1.
Explain the structure of a DNA molecule.
2. Which nucleotide bases pair together in DNA?
3. Are DNA in prokaryotes different than DNA in
eukaryotes?
Opening Assignment ANSWER
 Explain the structure of a DNA molecule. DNA is a
double helix structure made up of two rungs of
nucleotides each with a 5 carbon sugar, a phosphate
group, and a nitrogen base.
 Which nitrogen bases pair together in DNA?
Adenine pairs with Thymine and Cytosine pairs with
Guanine
DNA differences
DNA in Prokaryotes
DNA in Eukaryotes
DNA in Prokaryotes is less
complex and circular in
pattern made of a single
chromosomes
 DNA in Eukaryotes is
more complex and linear
in structure made of a
pairs of chromosomes
(One side from egg and
one from sperm)
More on DNA structure
The weak hydrogen bonds in between the nitrogen bases make it easy for
the double strand to be separated when DNA replication needs to occur.
Covalent bonds attach the sugar phosphaste backbone together and are a
stronger bond than the hydrogen bonds.
DNA to RNA to Protein
 Remember that DNA is a set of instructions to create
proteins. By itself, DNA does not do anything except
provide the instructions.
 The instructions are copied during a process called
transcription and carried out of the nucleus by a
molecule called Messenger RNA (mRNA).
DNA to RNA to Protein
 mRNA takes the copy to the Cytoplasm and
Ribosomes where the instructions will be read in a
process called translation and then proteins will be
made through a process called protein synthesis.
Amino Acids to Protein Molecules
 Remember that amino acids are the sub-
units of proteins!
 There are 20 different amino acids. Their
order in the protein molecule determines
its structure and function. Proteins may
serve e.g., as enzymes, hormones or
structural components of a cell.
 The final protein molecule may consist of
several hundred amino acids linked
together according to the instructions
encoded in the mRNA.
DNA, RNA and Protein Synthesis
 DNA vs. RNA
 https://www.youtube.com/watch?v=0Elo-zX1k8M
 Protein Synthesis
 https://www.youtube.com/watch?v=h5mJbP23Buo
Practice Question #1
Which of the following accurately describes the
difference between transcription and translation?
In transcription, the genetic code of a DNA molecule is first encoded.
Translation is the process of converting the DNA code into code that
RNA can use.
B. In transcription, an amino acid chain is encoded in a DNA molecule.
Translation is the process of turning the amino acids into nucleic
acids in an RNA molecule.
C. In transcription, the genetic code of a DNA molecule is transferred to
a messenger RNA molecule. Translation is the process of creating an
amino acid chain using the encoded messenger RNA.
D. In transcription, a double helix DNA molecule is split into two
separate single strands. Translation is the process of joining each
single DNA strand with a single strand of matching RNA.
A.
The Genetic Code
 The genetic code is nearly universal, meaning that
nearly ALL living organisms use the same genetic
code.
 All organisms encode genes using DNA and RNA.
 All organisms use the same codon for the same
amino acid.
 All organisms are genetically related to all other
organisms.
Universal Protein Codon Chart
Examples
UUA = leucine
CCC = proline
AGC = serine
Opening Assignment – Practice Question #2
The genetic code is universal, and is composed of
nucleotide triplets. Which of the following lists the
four types of nucleotide bases found in the nucleotide
triplets of a single strand of DNA?
A. ribose, thymine, glucose, uracil
B. adenine, cytosine, guanine, uracil
C. adenine, cytosine, guanine, thymine
D. adenine, deoxyribose, guanine, ribose
Practice Question #3
The genetic code is nearly universal, meaning that almost all
organisms use the same genetic code. Which statement does
NOT help explain why the genetic code is nearly universal?
All organisms encode their genes using DNA or RNA.
B. All organisms can grow, respond to stimuli, and
reproduce.
C. All organisms use the same codon for the same amino
acid.
D. All organisms are genetically related to all other
organisms.
A.
Practice Question #4
In a family with four children, both parents and three of the
children have brown eyes; however, the fourth child's eyes are
blue. Given these facts, which of the following statements is
false?
A. Both parents carry one blue-eye gene and one brown-eye
gene.
B. The brown-eye gene is dominant and the blue-eye gene is
recessive.
C. The blue-eyed child has one blue-eye gene and one
brown-eye gene.
D. It is possible that one of the brown-eyed children has two
brown-eye genes.
DNA Replication
 For a new cell to be formed through mitosis, the
DNA in the original parent cell needs to be
duplicated.
 This process is called DNA Replication and it
happens in the Interphase phase of Mitosis which
cells spend 90% of their time in.
DNA Replication Summary
 The process of DNA
replication involves the
double helix strand
unwinding and two new
strands are formed to
match up to the unwound
original parental DNA.
DNA Replication Summary
 Each newly synthesized
strand of DNA (daughter
strand) is made by the
addition of a nucleotide
that is complementary to
the parent strand of
DNA.
 In this way, DNA
replication is semiconservative, meaning
that one parent strand is
always passed on to the
daughter helix of DNA.
DNA Replication
 https://www.youtube.com/watch?v=GcrndR-zdyM
DNA Replication main points
1. DNA replication is the process of creating copies of the
original DNA from the parent cell to be used in the daughter
cells.
2. It starts when the DNA in the parent cell is unwound or
the bonds between the nitrogen bases are broken by an
enzyme called Helicase.
3. DNA Polymerase is the enzyme that matches up the
corresponding base pairs on both sides of the rungs to form
two new strands.
4. Each new strand has one side that is from the original
parent cell and one new side (Semi-conservative model).
Opening Assignment DUE AT 9:40
List two reasons that DNA is copied.
1.
2. Explain how these enzymes are used in the process
of DNA Replication.


A. Helicase
B. DNA Polymerase
Transcription vs. Translation
Create a venn diagram to compare and contrast the processes
of transcription and translation in protein synthesis
Transcription
Translation
Practice Question #3
Which of the following statements describes processes that occur during
DNA replication?
A. A DNA sequence is read by RNA polymerase, which produces another
RNA strand complementary to the first strand.
B. Two free-floating single strands of DNA are joined by polymerase.
The polymerase finds the point at which the two strands will match
up into a double strand
C. Messenger RNA are decoded by a ribosome to produce an amino acid
chain. In the cell's cytoplasm, transfer RNA join the messenger RNA,
forming a polypeptide.
D. A double-stranded DNA molecule is unwound into single strands.
Polymerase matches the right nucleotides to the single strand so that
each forms a double strand of DNA.
Today’s Activities
 Read Biology textbook lesson 13.3 on pages 372-376
 Define vocabulary and do workbook pages 201-204
 This assignment is due at the beginning of class
tomorrow.
Opening Assignment
 What is a mutation?
 List the three types of mutations and give an
example of how they each work.
 Have your workbook out and ready to be graded
pages 201-204 
Mutations
 Mutation is a natural process that changes a DNA
sequence. And it is more common than you may
think. As a cell copies its DNA before dividing, a
"typo" occurs every 100,000 or so nucleotides. That's
about 120,000 typos each time one of our cells
divides.
Mutations
 Most commonly, a single base is substituted for
another. Sometimes a base is deleted or an extra
base is added. Fortunately, the cell is able to repair
most of these changes. When a DNA change remains
unrepaired in a cell that will become an egg or a
sperm, it is passed down to offspring. Thanks to
mutation, we all have some new variations that were
not present in our parents.
Mutations
 People commonly use the terms "mutant" and
mutation" to describe something undesirable or
broken. But mutation is not always bad. Most DNA
changes fall in the large areas of the genome that sit
between genes, and usually they have no effect.
 When variations occur within genes, there is more
often a consequence, but even then mutation only
rarely causes death or disease. Mutation also
generates new variations that can give an individual
a survival advantage. And most often, mutation gives
rise to variations that are neither good nor bad, just
different.
Types of Mutations
 Point mutations are small (but significant)
changes often in a single nucleotide base or point in
the DNA sequence.
 3 types of Point Mutations are Substitution,
Insertion, and Deletion.
Substitution
 In a substitution mutation, one base is changed to a
different base.
 For example: In the normal strand
ATCGACT
A substitution can occur where G is replaced by T
ATCTACT
Because this only affects the codon of a single amino
acid these mutations can either have no effect or a
minimal one.
Point Mutations
 Insertions occur when one base is inserted from
the DNA sequence.
 For example: In the normal strand
ATCGACTGG
An insertion can occur where T is added to the strand
ATCTGACTGG
Point Mutations
 Deletions occur when one base is deleted from the
DNA sequence.
 For example: In the normal strand
ATCGACTGG
A deletion can occur where G is deleted from the
strand
ATCACTGG
Frameshift Mutations
 Both Insertion and
Deletion are also called
Frameshift Mutations
because they shift the
reading frame of the
genetic message.
 By shifting the reading
frame they can change
every amino acid after the
mutation.
 Amoeba Sisters – Mutations
 https://www.youtube.com/watch?v=GieZ3pk9YVo