Chapter 16. Reproductive System
Cellular reproduction in eukaryotic organisms.
Eukaryotic and prokaryotic cells? What is the difference?
Eukaryotic cells (animals, plants, fungi, protists).
What chemical carries a cell’s (organism’s) hereditary information?
What is a gene?
Where is most of a eucaryotic cell’s DNA located?
What is a chromosome and what does “linear” mean?
What is an exception to the rule that a cell’s DNA is to be found on linear chromosomes?
In human beings and most other organisms, the chromosomes come in pairs and the genes on them come in pairs.
The process of mitosis.
When ordinary cells reproduce (divide), they go through a process of mitosis wherein the cell’s chromosomes are duplicated and then equally distributed between the two newly formed cells (daughter cells).
Mitosis is a type of asexual reproduction.
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Asexual reproduction:
Offspring and parental organisms genetically identical.
What is a clone?
Sexual reproduction:
Offspring carry hereditary characteristics derived from two parents.
What is the biological advantage of sexual reproduction?
Meiosis and the Formation of Gametes:
Important information for understanding the mechanisms of heredity:
1. Chromosomes come in pairs.
2. A full set of chromosomes makes up the diploid (2N) number of chromosomes.
3. Sex cells contain only one member of each pair of chromosomes – half the diploid number or the haploid number (1N).
4. The process by which the haploid number is established in gametes is meiosis .
During the process of meiosis, a cell’s chromosome pairs are separated from one another and each resulting gamete has only one chromosome from each pair.
Reproductive Systems.
Gametes. What are gametes and what are the different kinds of human gametes?
What is the chromosome number in gametes?
Fertilization.
What is fertilization?
What happens to the chromosome number at fertilization?
What is a zygote?
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Sexual characteristics: what is the difference between primary and secondary sexual characteristics?
The male reproductive system. [Figure 16.2]
Structures:
Testis
Scrotum
Epididymis
Vas deferens
Urethra
Penis
Seminal vesicles
Prostate gland
Bulbourethral (Cowper’s) glands
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Sperm formation within the testes. [Figure 16.4]
Before the invention of the microscope, nothing could be known about sperm and ova.
What was the pre-scientific view?
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Hormonal control of the male reproductive system. [Figure 16.5]
Male hormones.
Female Hormones:
Early Development in the male embryo:
After Puberty:
GnRH = Gonadotropin releasing hormone.
FSH = Follicle stimulating hormone.
LH = Luteinizing hormone.
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The Female Reproductive System. [Figure 16.6]
Structures.
Ovary
Uterine tube (oviduct, Fallopian tube)
Uterus
Cervix
Vagina
Urethra
Labia major
Labia minor
Clitoris
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The ovary and the ovarian cycle.
[Figure 16.8]
Hormones and the female reproductive system. [Figure 16.9]
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The menstrual cycle. [Figure 16.10]
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Pregnancy and the menstrual cycle. [Figure 16.11]
Hormonal control of pregnancy.
First three months.
Last six months.
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