Download unit 6 reading guidE

Name: __________________________ Period: ___
Section 5.4
Heredity 2 Reading Guide
1. What are the two types of reproduction? (1) _________________________ (2) _______________________
2. Eggs and sperm are both specialized cells called __________________.
3. The offspring from sexual reproduction are genetically _________________________, because they have a
mixture of _______________ from both parents.
4. Asexual reproduction is the creation of offspring from a __________ parent and does not involve the joining
of ________________. The offspring that result are genetically _______________ to each other and to the
single parent.
5. Most prokaryotes reproduce through ____________________, which is the asexual reproduction of a
single-celled organism by division into ______________________________________________________.
6. Fill-in the following table with 2 advantages and disadvantages of asexual reproduction:
Advantages
Disadvantages
7. Some eukaryotes also reproduce asexually through _____________________________________________.
8. Complete the following table with descriptions/details of 3 forms of asexual reproduction in eukaryotes:
Type
Description/Details
Budding
Fragmentation
Vegetative
Reproduction
9. What forms of reproduction does the sea anemone use?
_______________________________________________________________________________________
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Name: __________________________ Period: ___
Section 6.1
Heredity 2 Reading Guide
1. What are the two major groups of cell types in the human body?
_______________________________________________________________________________________
2. What are somatic cells? ___________________________________________________________________
3. What are germ cells? _____________________________________________________________________
4. Where are gametes located in the body? ______________________________________________________
5. DNA in the ________________________ cells can be passed on to offspring.
6. What are homologous chromosomes?
______________________________________________________________________________________
7. Chromosome pairs 1 through 22 are __________________, which contain genes for traits not related to
gender, and the 23rd pair are the _________ chromosomes which __________________________________.
8. XX = ________________ XY = ________________
9. Are homologous chromosomes identical to each other? _____ Explain:
_______________________________________________________________________________________
10. The fusion of an egg and sperm is called _________________________.
11. Body cells have the ___________ chromosome number, while gametes have the _________ number.
12. Humans: haploid number (n) = __________, diploid number (2n) = __________
13. How many autosomes are present in each human gamete? _______ How many sex chromosomes? _____
14. Complete the following table to summarize the differences between mitosis and meiosis:
Mitosis
Meiosis
Makes diploid cells
Makes genetically unique cells
Happens throughout lifetime
Involved in sexual reproduction
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Section 6.2
15. Meiosis is a form of nuclear division that creates _____ haploid cells from one ____________ cell. This
process involves _____ rounds of cell division, with each round having _____ phases.
16. Meiosis reduces the ________________________ and creates ___________________________.
17. Homologous chromosomes are very similar to one another and carry the same genes, but they are not
_____________ of each other. In contrast, sister chromatids are _____________ chromosomes that remain
attached by the centromere.
18. In the box to the right, draw and label 1 pair of homologous chromosomes and each of the
4 sister chromatids.
19. In the following table, list each stage of meiosis and provide a brief description of each stage.
Meiosis I
Meiosis II
1.
1.
2.
2.
3.
3.
4.
4.
20. Homologous chromosomes separate in Meiosis _____, while sister chromatids separate in Meiosis _____.
21. What does sperm contribute to an embryo? ___________________________________________________
22. What does an egg contribute to an embryo? ___________________________________________________
23. How is spermatogenesis different from oogenesis?
_______________________________________________________________________________________
_______________________________________________________________________________________
24. What are polar bodies? ____________________________________________________________________
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Name: __________________________ Period: ___
Section 6.3
Heredity 2 Reading Guide
25. What are traits? _________________________________________________________________________
26. What is genetics? ________________________________________________________________________
27. Who laid the groundwork for much of our understanding of genetics? ______________________________
28. How did Mendel’s views on inheritance differ from the views of other scientists of his time?
_______________________________________________________________________________________
29. What were the 3 key choices Mendel made about his experiments:
(1) ____________________________________________________________________________________
(2) ____________________________________________________________________________________
(3) ____________________________________________________________________________________
30. What kind of organism did Mendel choose? ______________________ Why?
_______________________________________________________________________________________
31. What does purebred mean? ________________________________________________________________
32. What is a cross (in terms of genetics)? _______________________________________________________
33. Mendel concluded that traits are inherited as discrete units, which we now call _______________________.
34. What two conclusions make up Mendel’s law of segregation:
(1) ___________________________________________________________________________________
(2) ___________________________________________________________________________________
Section 6.4
35. What is a gene? _________________________________________________________________________
36. What is an allele? ________________________________________________________________________
37. Homozygous refers to when the 2 alleles are __________________________, while heterozygous refers to
when the 2 alleles are ________________________________.
38. What is a genome?
_______________________________________________________________________________________
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39. Genotype refers to the _______________________________________________ of a specific set of genes,
while phenotype would be the _____________________________ characteristics, or traits, of an individual.
40. What is a dominant allele?
_______________________________________________________________________________________
41. What is a recessive allele?
_______________________________________________________________________________________
42. Fill in the table below with the missing parts:
Genotype
Phenotype
Alleles
homozygous dominant
recessive
Tt
43. What factors besides alleles can affect phenotype?
_______________________________________________________________________________________
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Name: __________________________ Period: ___
Section 6.5
Heredity 2 Reading Guide
44. True or False: Gregor Mendel developed the Punnett Square.
45. What is a Punnett square?
_______________________________________________________________________________________
46. On a Punnett square, the axes represent _____________________________________ while the grid boxes
show ________________________________________________________________________________.
47. Why does each parent contribute only 1 allele to the offspring?
_______________________________________________________________________________________
48. A monohybrid cross involves _______ trait, while a dihybrid cross involves _______ traits.
49. What is the genotypic ratio of the offspring in Figure 6.15? _______________________________________
50. What is the phenotypic ratio of the offspring in Figure 6.15? ______________________________________
51. What is a test cross?
_______________________________________________________________________________________
52. What was the phenotypic ratio in the Mendel’s F2 generation dihybrid cross? ____________________
53. What is the law of independent assortment?
_______________________________________________________________________________________
54. Probability predicts the _________________ number of occurrences, not the __________________ number
of occurrences.
55. To calculate the probability that 2 independent events will happen together, __________ the probability of
each individual event.
56. In Figure 6.18, the probability of getting one coin that is heads up and one coin that is tails up is _________.
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Name: __________________________ Period: ___
Section 6.6
Heredity 2 Reading Guide
57. What is the major advantage of sexual reproduction?
_______________________________________________________________________________________
58. What are 2 ways that sexual reproduction helps create and maintain genetic diversity?
(1) __________________________________ (2) _______________________________________
59. Which does sexual reproduction create: new alleles or new combinations of alleles?
_______________________________________________________________________________________
60. How is the production of unique genetic combinations an advantage to organisms and species?
_______________________________________________________________________________________
_______________________________________________________________________________________
61. What is crossing over?
_______________________________________________________________________________________
62. In which phase of meiosis does crossing over occur? __________________ of Meiosis ____
63. Are chromosomes in a duplicated or an unduplicated state when crossing over occurs? _________________
64. Because crossing over results in new combinations of genes, it is also called _________________________,
which generally refers to any ______________________________________________________________.
65. Genes farther apart on a chromosome are more likely to be ______________ when crossing over occurs.
66. The tendency for 2 genes that are located close together on a chromosome to be inherited together is called
_______________________________________________________________________________________
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Name: __________________________ Period: ___
Section 7.1
Heredity 2 Reading Guide
1. What is a carrier?
_______________________________________________________________________________________
2. List the example provided of a disorder caused by a recessive allele:
_______________________________________________________________________________________
3. List the example provided of a disorder caused by a dominant allele:
_______________________________________________________________________________________
4. Mendel did not know about chromosomes; he only studied traits produced by genes on ________________.
5. What are genes called that are located on sex chromosomes? ________________________________
6. In humans, how does a gamete from a male determine the sex of the offspring?
_______________________________________________________________________________________
7. For what are the genes on the Y chromosome responsible? _______________________________________
8. How are sex-linked genes expressed differently in the phenotypes of males and females?
_______________________________________________________________________________________
9. What is X-chromosome inactivation?
_______________________________________________________________________________________
Section 7.2
10. What is incomplete dominance? ____________________________________________________________
Give an example: ________________________________________________________________________
11. What is codominance? ____________________________________________________________________
Give an example: ________________________________________________________________________
12. Traits produced by 2 or more genes are called ____________________. Example: ____________________
13. What is an epistatic gene? _____________________________________. Example: ___________________
14. Genes and ____________________ also interact to determine human traits. Example: _________________
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