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Flashcards in Chapter 26 Deck (15)
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1

Why are human testes located in an external sac rather than in the abdominal cavity?
a. to shorten the distance the semen has to travel during ejaculation
b. so the testes can be kept at a constant temperature
c. so the testes can be kept cooler than the body's interior
d. so the testes can enlarge at sexual maturity

c. so the testes can be kept cooler than the body's interior

2

In the seminiferous tubules the process of meiosis divides primary spermatocytes with ______ into ________.
a. 46 chromosomes into 1 cell with 23 chromosomes
b. 23 chromosomes into 4 cells with 23 chromosomes
c. 23 chromosomes into 1 cell with 23 chromosomes
d. 46 chromosomes into 4 cells with 23 chromosomes

d. 46 chromosomes into 4 cells with 23 chromosomes

3

A primary of oocyte is a _____
a. Diploid cell arrested during metaphase of Meiosis II
b. Diploid cell arrested during prophase of Meiosis I
c. Haploid cell arrested during metaphase of Meiosis II
d. Haploid cell arrested during prophase of Meiosis I

b. Diploid cell arrested during prophase of Meiosis I

4

Which of the following exists in the oviduct?
a. Secondary oocyte
b. Primary oocyte
c. Polar body
d. Primary spermatocyte

a. Secondary oocyte

5

Entry of the sperm triggers all of the following EXCEPT
a. Completion of Meiosis II
b. Production of a second polar body
c. Transition from secondary oocyte to mature egg
d. Transition from prophase I to metaphase I

d. Transition from prophase I to metaphase I

6

What is the function of the polar bodies that are produced in oogenesis? They are a mechanism that allows for ______
a. The removal of excess genetic material during the production of a haploid cell
b. The shedding of excess cytoplasm
c. The shedding of excess mitochondria
d. Streamlining the oocyte so as to facilitate the peneation of an oocyte by a sperm

a. The removal of excess genetic material during the production of a haploid cell

7

Into which layer of the uterus does the embryo implant?

The endometrium

8

Which of the following statements is true?
a. Oogenesis in humans is completed after stimulation by sperm
b. Meiosis in oogenesis produces 4 mature eggs from one primary spermatocyte
c. Oogenesis begin Sunday during puberty
d. Speratogenesis begins before birth

a. Oogenesis in humans is completed after stimulation by sperm

9

A sperm cell's acrosome
a. Contains the sperm's nucleus and is the part of the sperm that enters the egg during fertilization
b. Fuses with the plasma membrane of the egg cell
c. Contains enzymes that dissolve a hole in the jelly-like matrix that surrounds the egg
d. Contains the sperm's mitochondria

c. Contains enzymes that dissolve a hole in the jelly-like matrix that surrounds the egg

10

Types of asexual reproduction

Budding : outgrowth breaks off to form new offspring
Fission : parent separates into 2 offspring of equal size

11

Advantages/ Disadvantages of Asexual reproduction

No need to find a mate, good for isolation, happens very quickly as gametes don't neeed to be produced / not very much genetic variability

12

Sexual reproduction

Requires a mate, allows for genetic variability, no offspring will be a clone to the parent, can have artificial insemination

13

Internal VS External Fertilization

Internal fertilization occurs inside the female, while external fertiliztion occurs on a Petrie dish and then is implanted into the female's uterus after a zygote starts to develop

14

Structure of a sperm

Has a long flagella for movement, to "swim", has a streamlined body to help its aerodynamics, has a nucleus that contains its genetic material, has an acrosome,

15

Oogenesis vs Spermatogenesis

Oogenesis happens in females, spermatogeneiss happen in males, oogenesis produces eggs, spermatogeneiss produces sperm. A man will continue to make sperm, but a girl is born with all the eggs she will need