1. Cell Reproduction
Packet 7
Spring 2013

2. Notes: Introduction to Reproduction page 1

3. Why Reproduce?
Organisms must make more organisms in order for their own ____________ to survive.
___________ Reproduction – creation of a new organism by combining the genetic information from _____ different parent cells.
Creates genetic ______________; the offspring (new organism) gets half its DNA from each parent.
species
Sexual 2
variation

4. Why Reproduce?
_____________ Reproduction involves a single cell (or organism) reproducing by itself.
Process makes cells that are genetic ___________ (which means they’re identical to the original cell).
For single celled organisms (bacteria & yeast) – it is their primary means of reproduction.
Plants and Animals use this for ___________.
Cells in your body are often _____________ or _______ and must be replaced.
asexual
clones
Growth
damaged
die

5. WHY DIVIDE INTO SMALLER CELLS?
Specialization - Making many smaller cells instead of one large cell allows for cells to take on specialized tasks.
___________ cells are cells that have yet to become specialized. They can divide and become any type of cell in the body (which is called differentiation).
STEM

8. How much DNA is in our Cells?
While there are many different types of cells in our body, all of them contain the exact same genetic information contained in ____ chromosomes. 46
The diagram on the right, called a _______________ shows what the chromosomes from a single human cell look like when we stain them and match them up according to size & type.
karyotype

9. How much DNA is in our Cells?
Homologous Pairs
____________________ _______ are the two chromosomes that are paired together. They should have the same length and banding pattern.

11. How much DNA is in our Cells?
The last pair of chromosomes don’t look the same in males and females. These are called our _______ __________________
Females have two of the same (large) chromosomes which are referred to by the symbols _____.
Males have two different chromosomes,_______
___ is the larger sex chromosome
___ is the small one (about the same as the other chromosomes in the bottom row)
Sex Chromosomes
X X
X Y X Y

12. Notes: Asexual Reproduction page 2

13. Notes: Asexual Reproduction
ASEXUAL REPRODUCTION – division to form genetically identical cells or organism
Most common method of reproduction – one cell divides to form 2 genetically identical cells.

14. Notes: Asexual Reproduction
Prokaryotic (______________) Cell Division is called ________ __________
Since these are simple cells, the process occurs very quickly. One cell can become millions in 24 hours
Bacteria
Binary fission

15. Notes: Asexual Reproduction
DNA is copied. In a bacteria, the chromosome may be circular in shape.
_____________ - a ring of bacterial DNA.
Cell stretches longer and the two copies of DNA are split apart.
The cell pinches in, dividing to form two equally sized daughter cells.
plasmid

16. Other forms of Asexual Reproduction in Eukaryotic Organisms
budding
_____________ - term for reproduction in yeast (a ___________) and some simple animals such as sponges and hydra. A small version of the parent organism grows off of the parent.
fungus
Yeast cells reproducing asexually
Hydra reproducing asexually

17. Other forms of Asexual Reproduction in Eukaryotic Organisms
vegetative
___________________ Growth – a new plant can grow from an existing plant or its parts without the production of seeds or spores

18. Asexual reproduction allows humans to grow from a single cell to a baby made of trillions of cells.
more
As you continue to grow, your body makes __________ cells.
Cells must also continue to divide from birth to death to replace the cells that die each day.

19. 3 Steps in the Mitosis Cell Cycle:
_________ _________ - A series of steps that a cell goes through in order to form two identical daughter cells.
Mitosis
Cytokinesis
Interphase

20. 3 Steps in the Mitosis Cell Cycle:
1st _____________________ - cell prepares to divide
G1 = Cell __________________________________
S = DNA is copied (_________________________)
G2 = Cell __________________________________
interphase
Growth
Replication
Growth

21. 3 Steps in the Mitosis Cell Cycle:
2nd _________________: Chromosomes become visible & divide… 4 phases:
____rophase: X-shaped chromosomes form & nucleus disappears. P

22. 3 Steps in the Mitosis Cell Cycle:
_________________: Chromosomes become visible & divide… 4 phases:
_____etaphase : Chromosomes line up along center of the cell. M

23. 3 Steps in the Mitosis Cell Cycle:
_________________: Chromosomes become visible & divide… 4 phases:
____naphase: Duplicated chromosomes break in half A

24. 3 Steps in the Mitosis Cell Cycle:
_________________: Chromosomes become visible & divide… 4 phases:
____elophase: a new nucleus forms around each new set of chromosomes T

25. 3 Steps in the Mitosis Cell Cycle:
cytokinesis
3rd __________________: parent cell splits into two daughter cells

26. 3 Steps in the Mitosis Cell Cycle:
cytokinesis
3rd __________________: parent cell splits into two daughter cells

27. 3 Steps in the Mitosis Cell Cycle:
The daughter cells will then begin the cell cycle again in G1 of interphase.
Cells that can no longer divide enter a stage called G0.

28. metaphase
Prophase
Interphase
anaphase
telophase
cytokinesis

29. THE BAD SIDE OF CELL GROWTH:
Sometimes cells stop listening when your body tells it to stop making more cells. The body may be telling them to enter G0, but the cells continue to grow and divide.

30. THE BAD SIDE OF CELL GROWTH:
This uncontrolled cell growth, called ___________ is usually the result of a ______________ (or a mistake in the DNA). This can happen to any type of cell in the body
Leukemia is a form of cancer in which the body over produces ______________ blood cells at an alarming rate.
cancer
mutation
white

31. D A E C F B prophase cytokinesis anaphase interphase metaphase
Telophase

32. E B D C F A cytokinesis prophase anaphase metaphase interphase
telophase

33. Stages of the Cell Cycle page 6

34. Page 6 – Mitosis Review Binary Fission budding asexually interphase
1) What is reproduction in bacteria called? _______________. In yeast? ______________
2) Do yeast and bacteria reproduce sexually or asexually? ______________________________________________
3) Identify the name of the three major steps of the cell cycle:
________________________- A cell prepares to divide by growing and making a copy of its DNA.
________________________- The identical copies of DNA are split up & moved to opposite sides of the cell.
________________________- The cell pinches in half to form two smaller cells (each with the same genetic instructions as the original cell).
budding
asexually
interphase
mitosis
cytokinesis

35. Page 6 – Mitosis Review interphase replication mitosis Prophase
4) During ___________________ cells contain long thin strands of uncoiled DNA (chromosomes are not visible). 5) Since the DNA is not wound up, it can undergo _____________________ (an identical copy of the DNA is made) 6) At the start of ___________ the DNA coils up and forms chromosomes. These X-shaped chromosomes contain two identical copies of all the genetic information attached to one another. 7) The four stages of mitosis are (in order): ___________________________________________________ 8) After mitosis is complete, the parent cell divides to form two daughter cells during _______________________.
replication
mitosis
Prophase
metaphase
anaphase
telophase
cytokinesis

36. Page 6 – Mitosis Review A cell plate forms between the two new cells
9) How is cytokinesis different in plant cells and animal cells? Plant cells… _______________________________________ ___________________________________________________ Animal cells…_______________________________________ ___________________________________________________ 10) Why is it beneficial to be made up of many small cells rather than one or several large cells? _______________ _________________________________________________ 11) If a parent cell starts the cell cycle with 50 chromosomes, how many chromosomes will each daughter cell have when mitosis is complete? ________ Explain! _______________________________________________________________
A cell plate forms between the two new cells
A cleavage furrow pinches the cell membranes apart
They are able to be more specialized 50
Each daughter cell will be identical to the parent cell

37. Page 6 – Mitosis Review NO
12) Is there any genetic variation between cells that are produced by mitosis? _____________Explain why/why not? _________________________________________ 13) What is the connection between cancer and the cell cycle? __________________________________________________________________________________ _________________________________________ 14) If you had to put a caption below the picture on the right, how would you describe what this picture shows? _________________________________________ 15) Why are stem cells very important types of cells? _________________________________________________________________________________ NO
Each daughter cell will be identical to the parent cell
If the cell cycle continues after the cells
Should have entered G0, uncontrolled growth
will occur.
A stem cell differentiating into specialized cells
They have the ability to differentiate into
different specialized cells.

38. Notes: Sexual Reproduction page 7-8

39. Notes: SEXUAL REPRODUCTION
Sexual reproduction – making a new living organism by combining genetic information from _____ different parent cells. 2

40. 46 46 23 23 46

41. gametes
Human ____________ have only half the number of chromosomes as the rest of the cells in the body.
Male gamete = __________
Female gamete = ______
In humans, gametes contain
____ chromosomes.
sperm
egg 23

42. meiosis genetic variation
To make gametes, organisms must go through a process called ______________.
Meiosis results in offspring that have ______________ _______________. This increases the chance of species survival.
Instead of being identical to a parent, offspring are a random combination of traits from both mom and dad.
meiosis
genetic
variation

43. Meiosis I - ___ cell divides into ___ cells.
Meiosis is broken down into two major parts (Meiosis I and Meiosis II), each ending with a cell(s) dividing in half.
Meiosis I - ___ cell divides into ___ cells.
Meiosis II - __ cells divide into ___ cells. 1 2 2 4

44. 4
By the end, ___ daughter cells are made. Each cell has _________ the number of chromosomes as the rest of the cells in the body.
half

45. Meiosis in Males vs. Females: Spermatogenesis – meiosis in the _________. ____ sperm (male gametes) are made from a single cell.
Testes 4

46. ovaries 1
Oogenesis – meiosis in the __________ __ egg (female gamete) & ___ polar bodies are made from a single cell.
Polar bodies are not used for reproduction they’re only made to help split apart the genetic information (once made they simply die off). 3

47. Cells in your body are divided into two types.
______________ cells – cells that have only 1 set of chromosomes (half of the number of chromosomes as the body cells).
The only haploid cells in humans are ______ & _______
In humans, their haploid cells have ____ chromosomes.
Haploid
EGG
sperm 23

48. __________ cells - Cells with two sets of chromosomes (example: skin cell, muscle cell, liver cell… all the body cells).
All human cells (except for egg & sperm) are diploid cells. We call these body cells ____________ cells.
In humans, their diploid cell have ___ chromosomes.
Diploid
somatic 46

49. Sources of Genetic Variation
The greatest advantage of meiosis/sexual reproduction is a large amount of GENETIC DIVERSITY.

50. Sources of Genetic Variation
________________________________ - random alignment of homologous pairs at the equator… there’s nothing that says mom’s chromosomes line up on the left and dad’s on the right… it is random.
Independent assortment
In a normal human cell (with 23 pairs of chromosomes), independent assortment means that the same person could produce 223 = _____________ different combinations of their genes in their gametes.
8,388,608

51. Sources of Genetic Variation
____________________... During meiosis, your homologous chromosomes pair up. The chromosome from your mom and the one from your dad swap pieces (seen below):
Thanks to crossing over and independent assortment, each gamete is genetically different from another.
Crossing over

52. Sources of Genetic Variation
When you pair meiosis with sexual reproduction it creates even greater genetic variation in offspring.
__________________ is a result of random union of an egg with a sperm. The end result will be different each time… depends upon which sperm makes it to the egg first.
fertilization

53. Meiosis Overview page 9

54. 1) Meiosis creates cell that have _______ the number of chromosomes as the rest of the cells in the body.
2) What is a gamete? ____________________________________________________________________________________________
3) How many chromosomes are in a normal human gamete? _____
half
A reproductive cell made by meiosis
Examples: Egg & sperm 23

55. 4) Where in the human body does meiosis occur
4) Where in the human body does meiosis occur? Males = ________________; Females = ____________ 5) During spermatogenesis ____(#) _____________ cells are produced from a single cell. 6) During oogenesis ____(#) _______ cell and ____(#) polar bodies are produced from a single cell. 7) Give two reasons why the same person will never produce two gametes that are identical. _____________________________________________ ____________________________
testes
ovaries 4
sperm 1 3
egg
Independent assortment & Crossing over

56. 8) What is the advantage of making offspring through sexual reproduction (for both plants and animals)? ______________________________________________ 9) If a parent cell begins meiosis with 50 chromosomes, how many chromosomes will each daughter cell have when meiosis is complete? ______________ 10) Where does meiosis occur in an angiosperm (a flowering plant)? ______________________
Genetic Diversity 25
Anther & Ovules

57. asexual Sexual 2 4 increase limit Sperm & egg 46 23
Somatic cells (Body cells)
Ovaries & Testes
asexual
Sexual 2 4
diploid
Haploid
increase
limit
Skin, Digestive, etc.
Sperm & egg 46 23

58. Notes: When Mistakes Occur during Meiosis page 10-11

59. Notes: When Mistakes Occur During Meiosis
The ________________ to the right shows the chromosomes from a normal _________ (46XX).
karyotype
female

60. For an unborn baby, two methods are used to get fetal cells:
________________________ - removing some of the amniotic fluid that the baby is floating in; it will contain cells from the baby.
amniocentesis

61. CVS (chorionic villi sampling)
____________________________ - removing a piece of the placenta (which also contains cells from the baby).
CVS can be done earlier than amniocentesis – however, there is a greater risk of causing a miscarriage

62. Different methods can be used to obtain the cells for a karyotype:
To make a karyotype for an adult, a ___________ sample must be drawn.
Karyotypes are the easiest way to detect a mistake with the ____________ of chromosomes in a person’s cells.
Blood
number

63. The most commonly diagnosed condition in which a person’s cells have an abnormal number of chromosomes is __________ ________________. This occurs approximately 1 in every 700 live births in the United States.
Down syndrome 21 21
Edward Syndrome 13 13

64. Karyotypes are made when doctors suspect a possible mistake with the chromosome in a person’s cells. The most likely risk factors are:
________________________
Age of the ___________
(risk increases with age)
Family History
mother

65. 47 XY + 18 Male Edward syndrome They have an extra chromosome #18
How to read an abnormal Karyotype:
What is wrong with the individual’s karyotype shown on the right?
How would you write the genetic diagnosis?
Is it male for female?
What syndrome does this child have?
They have an extra chromosome #18
47 XY + 18
Male
Edward syndrome

66. Female x
Male
jacob Syndrome
Male

67. 47 XYY Male Jacob syndrome They have an extra Y chromosome
How to read another abnormal Karyotype:
What is wrong with the individual’s karyotype shown on the right?
How would you write the genetic diagnosis?
Is it male for female?
What syndrome does this child have?
They have an extra Y chromosome
47 XYY
Male
Jacob syndrome

68. What causes people to have the wrong number of chromosomes?
A mistake that occurs during meiosis causes an egg or sperm to be made that have the wrong number of chromosomes.
After 23 pairs of chromosomes line
up in the center of the cell, they
should separate. Instead one or
more pairs may stick together.
_________________________ is
the failure of the chromosomes to
separate during meiosis.
Nondisjunction

69. 23
In normal fertilization an egg with ____ chromosomes is fertilized by a sperm with ____ chromosomes. The fertilized egg should have ____ chromosomes.
If nondisjunction occurs an egg or sperm may have too ________ or too _______ chromosomes. 23 46
MANY
few

71. Usually a _________ with an abnormal number of chromosomes is ______________ by the body. However, if combinations are not lethal (not _________), the individual may survive to birth, but still be seriously affected.
Nondisjunction can occur with any of the chromosomes, but some are more common than others
zygote
miscarried
deadly

72. ___________ means that there is an extra (third) copy of a specific chromosome.
The issues that arise will depend upon which chromosome has three copies
In Down syndrome, there are three ____ chromosomes…. a total of 47 chromosomes in every cell.
Trisomy 21

73. ______________ is when a zygote that is missing one of their chromosomes.
Ex: ______________ Syndrome (45 XO) is an example of monosomy.
Monosomy
Turner

74. Test Review pages 13 & 14

75. mitosis
1. What process is occurring in these pictures? ______________________ 2. The correct order of the above pictures should be: ______  ______ ______ ______ ______ ______ 3. Which picture shows the parent cell? __________ Which picture shows the daughter cells? __________ C E A F B D c D

76. Somatic Cells (all body cells except for gametes)
4. What parts of your body are made by going through the above process: ____________________________________________________________ 5. Genetically, how do the daughter cells compare to the parent cell after mitosis & cytokinesis are complete? ______________________________ 6. What necessary process must occur in the parent cell before it is able to split into two cells? ____________________________
Somatic Cells (all body cells except for gametes)
Clones (identical)
DNA Replication

77. The bacteria is reproducing budding
7. What type of organism undergoes binary fission? _________________ How is binary fission different from mitosis? ______________________ _____________________________________________________________
8. What type of reproduction do yeast & hydra utilize? _______________. This is (sexual / asexual) reproduction? (circle one)
Bacteria
The bacteria is reproducing
budding
9. Which process is shown in the picture to the right? _______________________
Explain how you know this. ____________________________________________________________________________________________________________________________
Meiosis
The daughter cells
have half the number or chromosomes as the parent cell

78. Testes/Ovaries Sperm and egg Genetic diversity Pollen and eggs
Where does this process take place in your body? ________________
What kinds of cells are made by going through this process?
______________________________________
Why is it the benefit of going through this
process? ____________________________
What kinds of cells are produced by meiosis
in a flowering plant?
_______________________________
Testes/Ovaries
Sperm and egg
Genetic diversity
Pollen and eggs

79. Amniocentesis - A needle is used to extract amniotic fluid
What do you call cells that are able to become any type of cell in your body? _________________________
As these cells begin __d_____________________ they start to look like different types of cells. This is called cell specialization.
What is nondisjunction? How does it relate to meiosis? ____________________________________________________________ ____________________________________________________________
How are fetal cells obtained in order to do a karyotype (describe both methods we discussed in class)?
______________________________ - ________________________________ _______________________________________________________________
Stem cells
ifferentiation
When chromosomes don’t separate during meiosis; the gametes will have the wrong number of chromosomes
Amniocentesis A needle is used to extract amniotic fluid
Cvs A piece of the placenta is obtained

80. Male Down syndrome Extra 21st chromosome Edward’s syndrome
19. Give 2 examples of disorders caused by mistakes with the number of autosomes and describe the mistake?
______________________________ - ________________________________
20. Give 3 examples of disorders caused by mistakes with the number of sex chromosomes (describe mistake)?
21. What is the gender of a child that has XXYY for their sex chromosomes? _____________ Explain why. _________________________ _______________________________________________________________
Down syndrome
Extra 21st chromosome
Edward’s syndrome
Extra 18st chromosome
Patau’s syndrome
Extra 13st chromosome
Turner’s syndrome
Only an x sex chromosome
Triple x syndrome
XXX
Klinefelter’s syndrome
xxy
Jacob’s syndrome
xYy
not viable
Only an Y sex chromosome
Male
If there is a Y sex chromosome – it is a boy

81. 46 xy
Normal

82. 47 xX
Edward’s

83. 45 XO
Turner’s syndrome

84. Having a set of three chromosomes
22. What is trisomy? ____________________________________________ _____________________________________________________________
23. What does it mean if a karyotype had a diagnosis of a form of monosomy? ­­_______________________________________________ ____________________________________________________________
Having a set of three chromosomes
a pair is missing a chromosome

85. E D f G C I H A B