Chapter 41 - Human Reproduction Flashcards
(106 cards)
1
Q
What is the difference between sexual and asexual reproduction?
A
Sexual - 2 parents, gametes, variations
Asexual - 1 parent, no gametes, exact copy
2
Q
What are the three main parts of human reproduction?
A
Gonads,
Transport tubes,
Hormones
3
Q
What is the male gonad?
A
Testes
4
Q
What temperature is optimum for sperm?
A
35°c
5
Q
What is the epididymis?
A
Tubules (smaller tubes) that mature and store the sperm for up to six weeks
6
Q
What is another name for the sperm duct?
A
Vas deferens
7
Q
What is the function of the sperm duct?
A
Carry sperm to the prostate and into the urethra
8
Q
What is the function of the prostate, Cowper’s gland and seminal vesicles?
A
Produce seminal fluid
9
Q
What is seminal fluid?
A
An alkaline solution that nourishes the sperm
10
Q
Name the 2 glands in the male reproductive system.
A
Cowper’s gland and prostate gland
11
Q
What is semen?
A
Sperm + seminal fluid
12
Q
What is the function of the urethra?
A
Carries semen out of the body via the penis - dual function organ- releases urine
13
Q
What are the three parts of a sperm called?
A
Head
Collar
Tail
14
Q
What is the function of an acrosome?
A
At the top of the head of a sperm
Contains digestive enzymes so that is can enter an egg
15
Q
What is the function of the collar of a sperm?
A
Contains many mitochondria
16
Q
What does the nucleus of a sperm contain?
A
23 chromosomes
17
Q
What is another name for the tail of a sperm?
A
Flagellum
18
Q
Describe the lifecycle of a sperm.
A
Produced by meiosis once puberty begins
Continues to be produced for the lifetime of the male
Survives for up to 72 hours after ejaculation
19
Q
What produces hormones?
A
Pituitary gland
20
Q
What are the 3 hormones involved in the male reproductive system?
A
FSH
LH
Testosterone
21
Q
What does LH stand for?
A
Leuteinisng hormone
22
Q
What does FSH stand for?
A
Follicle stimulating hormone
23
Q
What is the function of FSH in a male?
A
Causes diploid sperm producing cells to divide by meiosis
24
Q
What is the function of LH in the male?
A
Stimulates testes to produce testosterone
25
What is the function of testosterone?
Causes primary (being born with male gonad) and secondary (puberty) male characteristics
26
What is a type of male infertility?
Low sperm count
27
What are 3 causes of male infertility?
Smoking
Alcohol and drug abuse
Low hormone levels
28
What is a correction method for male infertility?
Change in lifestyle
| Hormone treatment
29
What is the female gonad?
Ovary
30
What is the function of the ovary?
Produce eggs, all present at birth, one released each month
31
What is another name for the Fallopian tube?
Ovyduct
32
What is the function of the Fallopian tube?
Muscular tube
Funnels at tip - catches the egg as it’s released
Egg moved along tube by cilia and muscular peristalsis
Egg fertilized or dies here
33
What are the two parts to the uterus?
Inner wall - endometrium
| Outer wall - muscle
34
What is the cervix?
Opening to the uterus
35
What is the vagina?
Muscular tube
Allows entry of sperm and acts as a birth canal
Lined with mucous producing cells - protects again pathogens
36
What is ovulation?
Each month 20 eggs are produced by meiosis
37
What happens during days 1 - 5 of the menstruated cycle?
Endometrium breaks down and shed by the body
FSH released by pituitary gland
Meiosis occurs in ovary to create new egg
38
What happens during days 6 - 14 of the menstrual cycle?
Oestrogen produced by Graafian follicle - this stops FSH
Endometrium thickens
Allows one egg to develop
39
What happens on day 14 of the menstrual cycle?
Ovulation
| LH released by pituitary gland
40
What happens during day 14 - 28 of the menstrual cycle?
Progesterone released by corpus Leuteum -Endometrium thickens further, inhibits LH and FSH
No fertilization occurs progesterone levels decrease and the cycle starts again
41
What is the fertile period?
Days 11 - 16
Egg survives for 48 hours
Sperm can survive up to 72 hours
42
What are the four hormones in the female reproductive system?
Oestrogen
Progesterone
LH
FSH
43
What is the function of oestrogen?
Causes endometrium to thicken
Causes primary and secondary female characteristics
Made in the Graafian follicle (in ovary)
Inhibits FSH - ensures no further egg develops
High levels just before day 14 to stimulate LH
44
What is the function of progesterone?
Causes endometrium to thicken
Inhibits FSH - stops further eggs developing
Prevents contractions of the uterus
Made in the corpus leuteum
45
What is a form of female infertility?
Failure to ovulate
46
What is the cause of female infertility?
Hormonal disorder
Stress
Tumor
47
What is a corrective method for female infertility?
Hormonal treatment
Stress relief
Surgery
48
What are the 8 stages of human reproduction?
1. Gamete production
2. Copulation
3. Fertilization
4. Implantation
5. Placenta formation
6. Gestation
7. Birth
8. Lactation
49
Explains stage 1 in human reproduction.
Sperm and egg producing cells are diploid
They divide by meiosis to create haploid cells
Sperm nucleus (n=23) egg nucleus (n=23)
They combine to create a zygote (2n=46)
50
Explain the second stage of human reproduction.
Sexual intercourse - orgasm for male and females
Insemination - release of semen into the vagina outside cervix
Sperm moves to Fallopian tube - if egg is present it is attracted to it (chemotaxis)
51
Explain stage 3 of sexual reproduction.
Many sperm released - acidic conditions, attacked by whit blood cells
Fertilization occurs in Fallopian tube
Sperm and egg fuse - diploid cell created - zygote
Day 11 - 16
52
Explain the 4 stage of the reproductive system.
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The fertilized egg is embedded into the lining of the uterus
Day 6 - 9
Zygote develops into embryo
Amnion surrounds embryo
Amniotic fluid protects again shock
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53
Explain the 5 stage of reproduction
After implantation The embryo forms another membrane called the chorian
projections of the chorian called villi join with blood vessels in the endometrium to form the placenta
the placenta is fully functioning in about three months
umbilical cord connects the embryo at the Naval with the placenta
54
What does the placenta connect to?
The navel
55
What are the three functions of the placenta?
1. Exchanges substances between blood of the mother and the embryo - gases, hormones, wastes
2. Blood of the mother and the embryo do not mix - not compatible, blood pressure too strong
3. Endocrine gland as it produces hormones - progesterone
56
What is another name for birth?
Parturition
57
Explain the 7 stage of reproduction.
The placenta stops producing progesterone - causes the uterus to contract
Oxytocin is produces by the pituitary gland - contractions, beginning of Labour
58
What are the 3 stages of Labour?
1. Contractions push the foetus down towards the cervix - anion breaks, amniotic fluid is released through the vagina
2. Cervix dilates and foetus is pushed out through the cervix and vagina - umbilical cord is out
3. The placenta and foetal membrane are released through the vagina.
59
What is lactation?
Lactation is that secretion of milk by the memory gland of the female
60
What is colostrum?
Thick yellow fluid produced during the first few days of lactation
Low in fat and sugar but rich in minerals, protein and antibodies
61
What is prolactin ?
Hormone stimulates milk production - continues as long as breast feeding occurs
62
Name 4 benefits of breast feeding.
Nutrients and antibodies present
Safer for baby
May reduce risk of breast cancer
Helps mother recover from effects of pregnancy
63
What is ivf?
When the eggs are removed from the ovary and fertilized outside the body.
64
Name 3 reasons for ivf.
Blocked Fallopian tube
Inability to produce eggs
Low sperm count
65
What are the four steps to the ivf procedure?
Fertility drugs given to stimulate egg production
Day 14 eggs surgically removed
Mixed with sperm in glassware
If embryo is formed it is inserted into the uterus
66
What is abortion
The termination of pregnancy
67
What is contraception?
Taking measures to avoid pregnancy
68
What are the 4 methods of contraception?
1. Natural - understanding menstrual cycles
2. Mechanical - using physical barriers to prevent the sperm reaching the egg e.g. condom
3. Chemical - preventing ovulation using progesterone and oestrogen e.g. the pill
4. Surgical - getting the reproductive organs removed or cut e.g. vasectomy
69
Where are hormones made?
Pituitary gland
70
What days in the menstrual cycle is FSH present?
Days 1 - 5
71
What is the function of FSH?
Stimulates egg production
Used in partiality treatments - used to stimulate ovaries to produce eggs
Produces Graafian follicle
72
What is the Graafian follicle?
A follicle that surround an egg and produces oestrogen
73
Where is oestrogen produced?
Graafian follicle
74
What’s days in the menstrual cycle is oestrogen produced?
Days 5 - 14
75
What are the 3 functions of oestrogen?
1. Causes endometrium to develop
2. Inhibits FSH (this stops the production of eggs)
3. Stimulates LH on day 14 by increased levels
76
What stops the production of eggs?
Oestrogen
77
What days in the menstrual cycle is LH present?
Day 14
78
What are the 2 functions of LH?
1. Causes ovulation
| 2. Causes Graafian follicle to develop into corpus leuteum
79
What does the corpus leuteum do?
Makes progesterone and a small amount of oestrogen
80
What days in the menstrual cycle is progesterone present?
Days 14 - 28
81
What are the 4 functions of progesterone?
1. Maintains structure of endometrium
2. Inhibits FSH
3. Inhibits LH
4. Prevents contraction of the uterus
82
What happens to the corpus leuteum if pregnancy does not occur?
Starts to degenerate from day 22 which decreases level of progesterone
83
Where is progesterone made?
Corpus leuteum
84
What happens on day 28 if pregnancy does not occur?
Low levels of progesterone and oestrogen Leads to an increase in FSH which means new egg begins to develop
85
What happens when a new egg is produced?
The uterus contracts and endometrium is shed from the body
86
Name a menstruated disorder.
Fibroids
87
What is a tumour?
A tissue where the cells rapidly divide
88
What are the two types of tumors?
Benign - doesn’t invade other tissues
| Malignant - invades other tissues
89
What kind of tumor are fibroids?
Benign
90
What are the causes of fibroids?
Abnormal response to oestrogen
91
How can you prevent fibroids?
Frequent examinations
92
What is a treatment for fibroids?
Surgery
93
What does a zygote turn into?
A morula
94
On what day is a morula formed?
Day 3
95
What is a morula?
A solid ball of cells
96
What happens to a morula after fertilization?
It turns into a blastocyst
97
When does a blastocyst form?
5 days after fertilization
98
What is a blastocyst?
A hollow ball of cells
99
In a blastocyst there is inner cells and outer cells what is there function?
Outer cells - trophoblast which forms membrane around embryo
Inner cells - inner mass cells which have no function
100
What happens 10 days after fertilization to the blastocyst?
The inner cells (inner cell mass) forms an embryonic disc
101
What are germ layers?
Layers of the embryonic disc that form adult tissue and organs
102
What are the three germ layers?
Ectoderm
Endoderm
Mesoderm
103
What is the ectoderm?
The layer outside the body - skin, hair
104
What is the endoderm?
The layer inside the body - digestive, respiratory, excretory system
105
What are the 5 milestones of a developing embryo?
1. Heart forms (heartbeat), brain develops, umbilical cord
2. Internal organs and limbs
3. Features such as eyes, mouth, nose
4. Gender (ovaries/testes), tail bone goes, bone replaces cartilage
5. Nerves and muscles coordinate (movement), foetus sucks it’s thumb, urinates
106
On what weeks do the milestones occur?
1. Week 4
2. Week 5
3. Week 6
4. Week 8
5. Week 12
