Reproduction Review
1.
The critical features of mitosis:
a) Another name for mitosis is asexual reproduction
b) How many chromosomes does a normal human body cell have? 23 pairs
c) Are they in pairs or single? pairs
d) In the first stage of mitosis, what happens to the number of chromosomes? doubles
e) In the last stage of mitosis, how many chromosomes are present? 23 pairs
f) Are they in pairs? yes
g) How many cells are produced by mitosis? 2
h) In the human body, what is the function of mitosis? Growth, repair, replace cells
2.
The critical features of meiosis:
a) Another name for meiosis is sexual reproduction
b) How many chromosomes does a normal human body cell have? 23 pairs
c) Are they in pairs or single? pairs
d) In the first stage of meiosis, what happens to the number of chromosomes? doubles
e) In the last stage of meiosis, how many chromosomes are present? 23
f) Are they in pairs? NO!!!
g) In the human body, what is the function of meiosis? Making reproductive cells (sperm, eggs)
h) How many cells are produced by meiosis? 4
i) What type of cell is produced by meiosis in males? sperm
j) What types of cells are produced by meiosis in females? egg
3.
The chromosomes are made of what material? DNA
4.
How (in what shape) is this material arranged? Double helix
5.
Chromosomes code for genetic information.
6.
Inheritance of traits is controlled by sections of the chromosome called genes
7.
We get one set of these from our mother and one set of these from our father.
8.
There are 23 pairs chromosomes in a human, of which one pair(s) is/are sex chromosomes.
9.
These are called X and Y (i.e. What letter do we use to represent them?)
10. Females have two X chromosomes and males have an X and a Y chromosome.
11. There are two versions of each gene. One is the dominant gene and the other is the recessive gene.
12. If a person has a dominant gene, it overrides a recessive gene.
13. This means that the person will show the dominant trait, even though they have both genes.
14. There are thousands and thousands of genes. Some of these are located on the sex chromosomes. These
are called sex-linked genes.
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15. The traits for genes on the X chromosome are seldom expressed in females because they have two gene(s),
but are usually seen in males because they only have one gene(s).
16. Create a Punnett square for the mating of a female with heterozygous genes for narrow nose and a male
with a wide nose. (Narrow is dominant.)
N
n
n Nn nn
n Nn nn
a) What are the phenotypes for the offspring in the above Punnett square? 50% narrow 50% wide
b) What is the ratio of the genotypes? 50% Nn 50% nn
17. Create a Punnett square for the mating of two pea plants that are yellow seed hybrids. Yellow is dominant
over green.
Y
y
Y YY Yy
y
Yy
yy
a) What are the phenotypes for the offspring in the above Punnett square? ¾ yellow, ¼ green
b) What is the ratio of the genotypes? ¼ YY, ½ Yy, ¼ yy
18. Jim and Cathy have detached earlobes, but two of their five kids have attached earlobes. Detached earlobes
are dominant over attached.
a) Is it possible that he is the father of the children? Yes
b) Prove your answer by showing the possible genotypes of Jim and Cathy. Both are Ee
c) What are the odds that they would have a child with attached earlobes? (Hint: you can use a Punnett
square.) 25%
E
e
E EE Ee
e
Ee
ee
19. Dark hair is dominant over light hair colour. A person who is homozygous for dark hair marries a lighthaired person. What are the odds of the children having light hair? Prove your answer with a Punnett
square. 0%
D
D
d Dd Dd
2
d Dd Dd
20. Name five methods of asexual reproduction used in animals or plants. Give an example of an organism
that uses each method.
Binary fission
Budding
Fragmentation
Spore formation
Vegetative propagation
21. Complete the table, using as many entries as you can find in your notes or the text:
Method
Advantages
Disadvantages
Asexual
Don’t need a mate
No need for parents
All are identical, so one disease or one
change in environment could wipe out all
Young are as well adapted as parent
No parent to help young
Parent to help raise young
Need to find a mate
Variety! Young may be better than parent
Sometimes have to raise young
Variety! Less sensitive to disease or changes
in environment
Sometimes never find a mate
Sexual
Huge energy cost to find a mate
Young start out weak
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22. Define these terms:
a) Placenta Disc of tissue that allows the baby to exchange nutrients, oxygen and wastes
with the mother
b) Zygote Fertilized egg
c) Endometrium Thick lining of the uterus
d) Fetus Unborn infant in the later stages of development – after week 9 (has bone)
e) Embryo Unborn infant in the early stages of development – upto week 8
23. Freckles are dominant (F) over plain skin (f).
a) If a woman has plain skin and her husband is homozygous freckled, what are the possible phenotypes
for the children?
Husband is FF, woman is ff. All kids should have freckles.
b) Use a Punnett square to prove your answer.
F
F
f Ff Ff
f Ff Ff
24. The narrow nose trait is dominant (N) over the wide nose trait (n).
a) Use a Punnett square to show the genotypes for all the possible children for a heterozygous narrownosed man and a heterozygous narrow-nosed woman.
N
n
N NN Nn
n
Nn
nn
b) What are the phenotypes for these possibilities?
¾ narrow, ¼ wide
c) What is the ratio of the phenotypes? (See above)
25. Complete this table, telling the significant events during pregnancy. Focus on the physical changes in the
fetus.
Time from last menstruation
Changes in the fetus
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Summarize the first trimester Fertilization, implantation, infolding, some organs are
forming, heart and brain are forming, heart beats
Summarize the second
trimester
Organs are developing and maturing, fetus is growing, by the
end, all major organs are formed
Summarize the third
trimester
Development continues – mostly growth and weight gain
26. The modern cell theory (Fill-in-the-blanks):
a) All living things are made up of cells.
b) The cell is the functional unit of life.
c) All cells come from pre-existing cells.
27. What are the functions of these structures in human females:
a) Ovary Produces eggs and female hormones.
b) Uterus Organ which houses the developing fetus
c) Fallopian tube Tube that connects the ovary to the uterus
d) Cervix Muscular opening to the uterus, seals it off from the outside
e) Vagina Birth canal
28. What are the functions of these structures in human males:
a) Testis Produces sperm and male hormones
b) Prostate Provides fluid and nourishment for the sperm
c) Foreskin Protects the sensitive glans of the penis
d) Epididymis Region of testis where sperm are stored as they mature
29. A mosquito has 3 pairs of chromosomes.
a) If a body cell from a mosquito divides, what is this type of cell division called? Mitosis
b) How many chromosomes will the new body cells have? 3 pairs
c) If a mosquito produces sperm cells, what is this type of cell division called? Meiosis
d) How many chromosomes will the sperm cells have? 3
e) If sperm from a male mosquito fertilizes an egg from a female mosquito, how many chromosomes will
the new zygote have? 3 pairs
30. Define:
a) Meiosis Cell division producing four sex cells (gametes)
b) Mitosis Cell division producing two genetically identical cells
c) Gamete Sex cell
d) Chromosome Long strand of DNA found in the nucleus of a cell – contains the genetic information
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31. Label this diagram of the human female reproductive system.
a) Bladder
b) Cervix
c) Vagina
d) Labia minora
e) Labia majora
f) Clitoris
g) Urethra
h) Uterus
i) Ovary
j) Fallopian tube (oviduct)
32. Label this diagram of the human male
reproductive system.
a) Scrotum
b) Testis
c) Epididymus
d) Bulbourethral gland
e) Prostate gland
f) Seminal vesicle
g) Bladder
h) Vas deferens
i) Urethra
j) Glans
k) Prepuce (foreskin)
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