1. Unit 3: Growth and Heredity
Cells can grow only so big before they need to divide

2. Mitosis (Cell Division)
nucleus divides into two nuclei
number of chromosomes remain the same.

3. Mitosis Prophase (1st Phase) Chromosomes become visible
Continuous process
4 Stages of Mitosis
Prophase (1st Phase)
Chromosomes become visible
Cell part that contains genes that express traits that is located in the nucleus
Made up of thread-like material-chromatin
Control cell processes and determine traits of the entire organisms
Nuclear envelope dissolves
Spindle forms (centrioles)
Attach to chromosomes

5. Mitosis Metaphase (2nd Phase)
Chromosomes line up along the equator (middle of the cell)

6. Mitosis Anaphase (3rd Phase)
Centromeres divide ( connects the chromatids together)
Chromatids are single strands of chromosomes
Chromatids move toward opposite poles (spindle fibers are getting shorter)

7. Mitosis Telophase (4th Phase) Nuclear envelope forms at each pole
Chromosomes unwind
Cytokinesis begins

8. Mitosis and Cytokinesis
Cytokinesis-as mitosis ends this process begins
Cytoplasm divides
Forms two new cells
End result of mitosis and cytokensis: 2 diploid (2n) identical cells

9. Cytokinesis: Plants and Animals
Animals - cell pinches inward
Plants - a new cell wall forms between the two new cells

10. The cell cycle is carefully controlled
Checkpoints (traffic lights)-check for errors, correct mistakes and stop the process.

11. Mitosis
Purpose:
Replace old and worn out cells lost by wear and tear. Ex. Skin shedding
Required to sustain life
Immature human=growth
Mitosis
Type of Cells that divide in this process
Body cells (hair, skin etc.)

12. Meiosis
Process by which gametes (reproductive cell) are formed (egg and sperm cells)
Sperm Cell-male reproductive cell
Egg Cell- female reproductive cell
Gametes contain half the number of chromosomes as body cells.
Because offspring will get a copy of genes from each parent.
Example: Female Gamete=23 chromosomes and Male Gamete=23-Zygote (fertilized egg has 46 chromosome)

13. Meiosis
Form of cellular division that halves the number of chromosomes
Two cell divisions-meiosis I and II
Total of eight phases
Starts with homologous chromosomes
are similar in shape and content
End result: 4 haploid (n) genetically different cells.

14. Chromosomes
Made up of thread like material (DNA) called chromatin (prophase)
Located in the nucleus (control center of the cell)
Control cell processes and determine the traits of the entire organisms (hair color, height , eye color etc.)
Comprised of two sister chromatids (single strand of chromosomes) that are identical in content
During cell division, each chromosome makes an exact copy of itself.
Genes ( part of chromosome that controls inherited traits-eye color, height, etc.) are located on different parts of chromosome

15. Chromosome Structure (Draw)

16. Meiosis Graphic Organizer (Recopy)
MEIOISIS 1 n n
MEIOISIS 2 n n n n

17. Purpose of Meiosis
Primary purpose is to increase genetic variations (differences)

18. Meiosis Provides Variations (Differences)
3 mechanisms contribute to genetic variations (Differences)
Independent assortment, crossing-over and random fertilization

19. Independent Assortment
Random distribution of homologous chromosomes during meiosis (genetic shuffling)
Siblings look similar but different because they have some genes in common.

20. Random fertilization Only one sperm will enter the egg
Only one sperm will fertilize an egg
Each sperm carries a different combination of genes
Allows for unlimited genetic combinations
Only one sperm will enter the egg

21. Crossing Over Occurs in Prophase I
Portion of one homologous chromosome is exchanged with a portion of another homologous chromosome

22. Importance of Genetic Variation
Increases the speed of evolution (change)
Allow favorable traits (thick fur) to pass from one generation to the next that increase chances of survival

23. Asexual Reproduction (Mitosis)
Asexual reproduction-a single parent passes copies of all of its genes to each of its offspring
Clone-organism that is genetically identical to its parent

24. Sexual Reproduction (Meiosis)
Sexual reproduction-two parents each form haploid reproductive cells (sperm and egg), which join to form offspring.
Have traits from both parents
Not exactly like parents

25. Advantages of and Disadvantages of each type of reproduction
Asexual reproduction:
Disadvantage: lack of diversity that threatens the ability of the organisms to adapt in a changing environment
Advantage: allows organisms to produce many offspring in a short period of time without using energy

26. Advantages of and Disadvantages of each type of reproduction
Sexual Reproduction:
Advantage: enables organism to adapt to changing environment
Disadvantage: requires lots of energy and produce only a few organisms at a time.

27. Haploid (n)
egg
Haploid (n)
sperm
Diploid(2n)
zygote

28. Venn Diagram: Asexual vs. Sexual Reproduction
Insert the following terms into the right part of the circle.
1. one parent
2. two parents
3. clone
4. different from parent
5. requires more energy
6. difficulties adapting to a changing environment
List two similarities in the middle
Explain why genetic differences are important?

29. Heredity
Many of your traits (characteristics of an organism)-eye color, hair color-resemble your parents.
Inherited traits: traits that are passed from parents to their offspring.
Eye Color
Heredity-passing of traits from parents to offspring
Study of heredity began with Gregor Mendel
Genetics-focuses on heredity

31. Mendel’s Studies Based his hypotheses on pea plants
Concluded the following:
1. An individual inherits two copies of a gene-one from each parent

32. Mendel’s Theories 2. There are alternative versions of genes
Ex. Flower Color: purple and white

33. Mendel’s Theories 3. Some traits are expressed and others are hidden.
Dominant: gene whose trait always shows itself
Recessive: gene of a trait that is hidden when the dominant gene is present.

34. Mendel’s findings in modern terms
Homozygous-two alleles are the same
Ex. AA or aa
Heterozygous-two alleles are different
Ex. Aa
Heterozygous only dominant trait is expressed
Ex. F=freckles f=no freckles Ff=

35. Mendel’s findings in modern terms
Genotype-set of alleles (letters) ex. Ff
Phenotype is the physical appearance ex. Freckles

36. Mendel’s Ideas Give Rise to the Laws of Heredity
Law of segregation-
Alleles for a trait separate when gametes are formed.
These allele pairs are then randomly united at fertilization (uniting of the egg and sperm to form zygote (fertilized egg)

38. Studying Heredity
Punnett Squares-chart that shows possible gene combinations
Organisms have at least two genes for most traits.
An uppercase letter represents a dominant trait
A lowercase letter represents a recessive trait

39. Mini Lab Follow procedures found on p. 281
Answer analysis questions after completing the punnett square problems.

40. Left Side Divide page into six and define the following terms:
Homozygous, heterozygous, phenotype, genotype, dominant and recessive
For each term complete the following:
Definition, drawing , and sentence using the term correctly (put sentence in a box).

41. Acquired Traits vs. Inherited Traits
Acquired Traits are traits that you learn because of the environment that you live in.
Example: favorite color or favorite food
Inherited Traits are traits that are passed from generation to generation by genes inherited from your parents.
Ex. Eye color, hair color.

42. Non-Mendelian Patterns of Inheritance
All human traits are determined by 23 pair (46 chromosomes) of chromosomes.
23rd pair are not alike
Males=XY
Females=XX
The X and Y chromosome determine gender (male or female)
All eggs contain X chromosomes
Sperm cell can contain either a X or Y chromosome
Gender is inherited (determined) from the father

43. Sex-Linked Trait
Sex-Linked Traits-traits that are inherited along with gender.
X chromosomes carries many genes
Y chromosome carries few genes
Most genes for sex-linked traits are found on the X chromosome.
Sex-linked disorders are found more often in men than women.
Most genes for sex-linked disorder is recessive
Men only have one X chromosome
If they inherit trait they will have the disorder.

44. Patterns of Heredity
Polygenic trait-traits that are influenced by several genes.
Ex. Hair color, skin color, weight, height, and eye color

45. Intermediate traits
Incomplete dominance- pattern of inheritance in which alleles from both parents are blended.
Ex. red flower is crossed with white flower-offspring pink flowers

47. Traits with two forms
Co-dominance- pattern of inheritance in which both alleles of a gene is expressed.
Ex: Both red and white will be displayed on the flower

48. Jumping Genes (Genetic Variation)
Genes that move around or jump around and relocate.
Create new genetic combinations
Only take place on certain genes (wouldn’t want your heart genes jumping around and relocating)

49. DNA Blueprint of the organism
Controls everything about the way that you look( color of your eyes to width of your feet)
Transfers characteristics from one generation to the next

50. The structure of DNA Watson and Crick determined the structure of DNA
Three dimensional model
DNA
Double helix-two strands twisted around each other like a winding staircase
Each strand is made of linked nucleotides
Made up of three parts: phosphate group, a five-carbon sugar, and a nitrogen-containing base.
Five carbon sugar: deoxyribose

51. Structure of DNA.
4 Nitrogen bases- adenine(A), guanine(G), thymine(T), and cytosine(C)
Double helix is held together by weak hydrogen bonds

52. Base Pair Rule
Rule that explains how nitrogen bases pair up on the DNA molecule
A (adenine) pairs with (T) Thymine
Guanine (G) pairs with Cytosine (C)
Build a DNA Molecule

53. The Replication of DNA Takes place in interphase
Process of making a copy of DNA
DNA molecule unzips between nitrogen bases
New nitrogen bases pair up and attach to each half of the ladder.
Two new DNA strands that are exact copies of the original DNA molecule

54. Checking for errors DNA polymerase: proofread role
Corrects mistakes in nucleotide bases

55. Left Side Assignment
Write an analogy story that relates to each step of DNA replication. Each paragraph should relate to each step of replication.
Step 1: something unzips
Step 2: something is added
Step 3: a copy is made
This should be written in color.

56. Expression of Traits
Traits such as eye color are determined by proteins
Specific instructions are found on DNA
Proteins are not built directly from DNA
Too large to fit through the nuclear pores

57. RNA Is a special molecule that is used to make proteins
Ribonucleic Acid (RNA)
Different from DNA in many ways
Single stranded
Has a new nitrogen base: uracil
Does not have thymine
Different sugar: ribose

58. From Genes to Proteins
Gene Expression
Step one: instruction are transferred from DNA to RNA molecule in process called transcription
Step Two: Translation (takes place in cytoplasm)-process in which cell uses two different RNA molecules to read the instructions on the RNA and put together the amino acids that make up proteins
tRNA: transfers the amino acids to the ribosome's site of protein synthesis

59. The Genetic Code is Written in Three-Nucleotide “Words”
Codons-series of three-nucleotide sequences on the mRNA (messenger RNA) that translate into the amino acids that make proteins.
EX. AUC codes for the amino acid_______

60. From Genes to Proteins
SIMPLY PUT: DNA makes RNA makes Proteins make traits( such as eye color, skin color and hair color)

61. Mutations Any change in an organisms genetic material.
Can be harmful if it decreases the organism’s ability to function properly.
Abnormalities can be detected in a karyotype.
A photo of the chromosomes

63. Two Types of Mutations
Gene Mutations: result from changes in a single gene
Chromosomal Mutations: involve changes in an entire chromosome.
Deletion- a piece of a chromosome breaks off
Duplication-two copies of a certain set of genes

64. Point Mutations Change in one or just a few nucleotides
Sickle Cell Anemia is caused by this type of mutation.

65. Mutations Cont.
Mutations in gametes (egg and sperm) can be passed on from generation to generation.
Color blindness
Mutations in body cells (somatic cells) affect only one individual.
Lung cancer

66. Down Syndrome (Mutation)
Caused by extra copy of 21st chromosome (non-disjunction-when one or more chromosomes fail to separate)
Individuals with this condition
Short stature, a round face , and varying degrees of mental retardation.

68. Mutations External influences can create mutations.
Mutations can be caused by exposure to specific chemicals or radiation
Example: Lung Cancer
Chemicals found in the cigarettes cause mutations in lung cells.
Example: Skin Cancer
Ultraviolet Rays cause mutations in skin cells.

69. Lung Cancer

70. Skin Cancer

71. Detecting Genetic Disorders
Most can not be cured.
Persons’ with family history may wish to undergo genetic counseling.
Genetic Counseling- medical guidance that informs people about genetic problems that could affect them or their offspring.

72. Genetic Engineering Methods used to produce new forms of DNA.
Involves building NEW DNA by taking genes from one species and inserting them into a completely different species.
Examples of Genetically Engineered Items
1. Tomatoes with elephant genes (make the tomatoes grow larger)

73. Benefits of Genetic Engineering
Medicines to treat disease such as diabetes.
Identify individuals and establish relationships -DNA fingerprinting

74. Benefits of Genetic Engineering
Add favorable characteristics to a plant
Resistant to pest or pesticides
Tolerate harsh environmental conditions such as drought

76. Benefits of Genetic Engineering
Improve farm animals
Cows that produce more milk (more productive)
Make medically useful proteins for humans
Produce transplant organs for humans

78. Disadvantages
Experimenting with Bacteria can cause new diseases with no cure.
Federal Government regulates experiments because of danger.

79. Questions
Create three questions and a two sentence summary for your notes.
Make sure you write your questions next to the answer in the notes.
Make one of your questions a How?

80. Snappy Products
You are a design team for a small biotechnology company.
Your Job is a follows:
1. Brainstorm a list a ways that you can improve popcorn.
Ex. Popcorn that pops faster
2. Think of something else that has the desired trait that you want to see in your popcorn.
3. Combine the solution that you thought of in #2 with popcorn, make the “the popcorn” that can solve the problem that you mentioned in #1.
Assignment: Draw your new popcorn product, be sure to clearly show what other product that you combined with your popcorn to create something new.
Create a catchy name for you product
Write a tune with words to be used to as a radio commercial. Include your price in your song.