1. Interim 2 review

2. Meiosis- forming sex cells
Process in which haploid cells are formed from diploid cells
In humans:
Parent Parent
Diploid (2N) Diploid (2N)
Ovum Sperm
Haploid (N) Haploid (N)
Zygote 46
Diploid (2N)
Chromosome number cut in half
Fertilization

3. Mitosis vs Meiosis Characteristic Mitosis Meiosis Cells produced
Body cells (somatic cells)
Sex cells (gametes)
Chromosome number
Same as parent cell
Diploid 2N
Half number of parent cell
Haploid N
Number of divisions 1 2
Number of cells produced 4

4. Meiosis
Meiosis I
Meiosis II

5. Meiosis homologous Cut in ½ chromatids
During meiosis I, the ______________________ chromosomes separate.
What does this do to the chromosome number?
During meiosis II, the sister ____________________ separate.
homologous
Cut in ½
chromatids

6. Meiosis I

7. Meiosis II
Prophase II Metaphase II Anaphase & Telophase II

8. Meiosis in Males and Females
Males- results in 4 sperm cells
Females- results in one ovum (egg) and 3 polar bodies
MALES FEMALES
1st cell division
2nd cell division
4 Sperm cells polar bodies 1 ovum

9. If three cells undergo meiosis in males, how many sperm cells will be produced? _____________
If four cells undergo meiosis in females, how many ova (eggs) will be produced? _____________
How many polar bodies would be produced for the same 4 cells? __________________ 12 4 12

10. 16 32 16 16 32 If the 2N number of an organism is 32;
how many chromosomes are found in a sperm cell? _______
how many chromosomes are found in a diploid cell? _______
how many chromosomes are found in an ovum? _______
how many chromosomes are found in a haploid cell? _______
how many chromosomes are found in a skin cell?________ 16 32 16 16 32

11. .
Sexual reproduction is important to the survival of the species because it adds genetic _________________________ to the population.
variation

12. Genetic variation
Crossing Over- exchange of genetic information by non- sister chromatids during meiosis.

13. Mistakes in the Meiosis
Nondisjunction- failure of chromosomes to separate properly

14. Genetics Vocabulary
________________- the passing of traits from parents to offspring
________________- the study of heredity
_________________- rod-shaped structures in the nucleus that transmits genetic information
_________________- units of hereditary information found on the chromosomes
heredity
genetics
chromosomes
genes

15. Genetics Vocabulary
__________________- a gene that masks the expression of another gene in a pair ( Symbol- capital letter)
__________________- a gene in a pair that is hidden by the dominant gene (Symbol- lower case letter)
___________________- two genes in a pair that are identical. (RR or rr)
_____________________- individual with one dominant and one recessive gene in a pair. (Rr)
dominant
recessive
homozygous
heterozygous

16. Genetics Vocabulary
______________________- either member of a pair of genes that determines a single trait.
____________________- the pair of alleles represented by the capital and lower case letters.
______________________- the trait that is actually expressed in an organism
allele
genotype
phenotype

17. Immunity to poison ivy is a dominant trait while those people who get poison ivy show the recessive trait. Diagram a Punnett Square for a man who is heterozygous and a woman who get poison ivy.
I i
1. What is the man’s genotype? ___________
2. What is the woman’s genotype? ____________
3. What is the probability of producing a child who gets poison ivy? __________
4. What is the genotypic ratio?___________ Ii i Ii ii ii Ii ii
50%
1:1

18. Feather color in birds is an incomplete dominant trait
Feather color in birds is an incomplete dominant trait. Genes for blue feathers and genes for white feathers combine to form birds with silver feathers. Diagram a cross for two silver feathered birds.
B W
1. What is the parent’s genotype? ___________
2. What is the phenotypic ratio? ____________
3. What is the probability of producing bird with blue feathers? __________
4. What is the probability of producing a bird with silver feathers?___________ BW B W BB BW
1:2:1
25% BW WW
50%

19. AA, AO, AB, BO A O 1:1:1:1 2:1:1 A B AA AO 50% AB BO
Blood type is a codominant trait. A man with blood type AO marries a female with blood type AB.
1. What are the genotypes in the offspring? ___________________
2. What is the genotypic ratio? ____________
3. What is the phenotypic ratio? __________
4. What is the probability of producing a child with blood type A? _______
5. What is the probability of producing a child with blood type O? ______
AA, AO, AB, BO
A O
1:1:1:1
2:1:1 A B AA AO
50% AB BO

20. XBY Xb Xb Xb Xb XB Y XBXb XBXb 50% XbY XbY 50%
Eye color in canaries is a sex-linked trait. Black eyes are dominant and red eyes are recessive. A red-eyed female is crossed with a black-eyed male.
What is the male’s
genotype? __________
2. What is the female’s genotype? _________
What is the probability of producing a
3. black-eyed female? _______
4. black –eyed male? _______
5. red-eyed female? ________
6. red-eyed male? __________
XBY
Xb Xb
Xb Xb XB Y
XBXb
XBXb
50%
XbY
XbY
50%

21. phosphate sugar base Label the three parts of the nucleotide below.
______________
B.______________
C.______________
sugar
base

22. In DNA, how do the bases bond?
_____________ bonds with ____________
and
Adenine Thymine
Cytosine Guanine

23. What is the name of the process in which DNA makes an exact copy of itself? __________________________
Replication

24. 3 1 2 4 Put the steps of DNA replication below in order.
1. Free floating nucleotides attach to complementary bases on both sides
2. Sugars and phosphates join together on the new strands
3. DNA molecule unzips
4. Two DNA molecules are produced each made of one new strand and one template
________→ ________→ ________→ ________ 3 1 2 4

25. Comparison of DNA and RNA
Strands
Sugar
Base Pairs
Location 2 1
deoxyribose
ribose
A with T
C with G
A with U
C with G
Nucleus to cytoplasm
nucleus

26. Transcription nucleus Translation cytoplasm ribosome
Protein Synthesis is divided into two processes.
Process 1- _____________________________-mRNA is made by copying the code from a DNA molecule.
This process occurs in the __________.
Process 2-_____________________________- a protein is assembled from amino acids.
This process occurs in the _______________ at a _____________________.
Transcription
nucleus
Translation
cytoplasm
ribosome

27. Genetic information usually follows in one specific direction (Central dogma of biology). Which of the following BEST represents this flow?
A.) DNA-->Protein-->RNA
B.) Protein-->RNA-->DNA
C.) RNA-->Protein-->DNA
D.) DNA-->RNA-->Protein

28. Three bases on the mRNA molecule that code for one amino acid is a(n)
A.) anti-codon.
B.) codon.
C.) tRNA.
D.) protein.

29. C U G A A U G U C Transcribe the section of DNA below.
G A C T T A C A G
C U G A A U G U C

30. 5 4 1 3 2 tRNA Amino acid mRNA Protein ribosome
Label parts 1 through 5 in the diagram.
1. _______________ 4. _______________
2. _______________ 5. _______________
3. _______________ 5 4 1 3 2
tRNA
Amino acid
mRNA
Protein
ribosome

31. 5 4 1 3 2 Translation What is the name of the process in the picture?
_____________________ 5 4 1 3 2
Translation

32. Mutation Insertion Deletion Substitution
A mistake in the genetic code is called a ____________________.
Name the type of mutation in the DNA sequences below. Use these choices
Substitution Insertion Deletion
Original strand – CTGACT
New strand CTAGACT ___________________
New strand CTGCT ___________________
New strand CTGAGT ___________________
Mutation
Insertion
Deletion
Substitution

33. Gel Electrophoresis DNA fingerprinting
___________ ____________________ is a method used to separate and analyze DNA fragments.
__________ ____________________ is the analysis of DNA fragments to identify an individual.
DNA fingerprinting cs s1 s2 s3 s4 s5
CS= crime scene DNA
s1= suspect 1
s2= suspect 2
s3= suspect 3
s4= suspect 4
s5= suspect 5