Exam 3 Flashcards
(114 cards)
1
Q
Gametogenesis
A
Process of formation and development of specialized generative cells (gametes) from bipotential primordial germ cells
2
Q
When do females begin producing oocytes?
A
In utero
3
Q
When do males begin producing sperm?
A
At puberty
4
Q
Chromatid
A
One of two identical halves of a chromosome that has been replicated in preparation for cell division
5
Q
Centromere
A
Connect the two sister chromatids together
6
Q
What forms a zygote?
A
The fusion of a sperm and egg
7
Q
Interphase I
A
Chromosomes replicate + centriole pairs replicate
8
Q
Meiosis I
A
Cell division that reduces the chromosome number by half. Separates pairs of homologous chromosomes
9
Q
Prophase I
A
Chromosomes condense + homologous chromosomes pair/exchange dna
10
Q
Prometaphase I
A
Spindle apparatus forms
11
Q
Metaphase I
A
Homologous pairs arranged at metaphase plate (middle of cell)
12
Q
Anaphase I
A
Homologous chromosomes are separated + pulled to opposite ends of cell
13
Q
Telophase I
A
Nuclear membrane forms
14
Q
Cytokinesis I
A
Cytoplasm + cell membrane pinch off around the two new nuclei to form 2 haploid cells
15
Q
Tetrads
A
Homologous pairs that carry genes controlling the same inherited traits
16
Q
Karyotype
A
Method of organizing the chromosomes of a cell in relation to #, size, + type
17
Q
Crossing over
A
Segments of no sister chromatids break + reattach to the other chromatid
18
Q
What are the sites where cross over occurs called?
A
Chiasmata (chiasma)
19
Q
Prophase II
A
Chromosomes condense + nuclear membrane dissolves
20
Q
Metaphase II
A
Spindle fibers attach to chromosomes + they line up in middle of the cell
21
Q
Anaphase II
A
Centromeres divide + sister chromatids move to opposite ends of cell
22
Q
Telophase II + cytokinesis
A
Chromosomes reach opposite ends + nuclear membrane forms
23
Q
Meiosis II
A
Produce 4 haploid daughter cells
24
Q
What hormones does the pituitary gland produce?
A
Follicle-stimulating hormone + luteinizing hormone
25
What hormone is secreted by the hypothalamus?
Gonadotropin releasing hormone (GnRH)
26
Spermatogenesis
Transformation of spermatogonia into mature sperms
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Spermiogenesis
Last step of spermatogenesis. Process of sperm maturation
28
Spermatogonium
Undifferentiated male germ cell
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Spermatogonia type A dark
Do not undergo active mitosis
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Spermatogonia type A pale
Undergo active mitosis. Divide to produce type B cells
31
Spermatogonia type B cells
Divide to give rise to primary spermatocytes
32
Sertoli cells
Somatic cells of the testes that are essential for testis formation
33
Spermatogonium
First cells of spermatogenesis
34
Primary spermatocytes
Enter prophase I + appear larger than spermatogonia
35
Secondary spermatocytes
Smaller than primary spermatocytes. Enter + complete meiosis II
36
Spermatids
Immature sperm cells
37
Spermatozoa
Mature human spermatozoon. Includes tail, head, + neck
38
Capacitation
capacitated sperms bind to a glycoprotein on zona pellucida during fertilization
39
How long do ejaculated sperm undergo capacitation for?
7 hours
40
Oogenesis
Look for video! Slides don’t make sense
41
Perimetrium
Thin external layer of uterus
42
Myometrium
Thick smooth muscle. Middle layer of uterus
43
Endometrium
Thin, internal layer of uterus. Consists of compact layer, spongy layer, basal layer
44
What do the ovaries produce?
Oocytes + hormones
45
Follicle stimulating hormone
Stimulates development of ovarian follicles + production of estrogen
46
Luteinizing hormone
Trigger for ovulation + stimulates follicular cells + corpus luteinizing to produce progesterone
47
Ovarian cycle
Watch a video
48
What is a mature follicle called?
Graafian follicle
49
Menstrual phase
Functional layer of uterine wall is sloughed off due to decreased progesterone. Lasts 4-5 days
50
Proliferation phase
9 days of follicular growth + endometrial thickness growth. More blood flow to tissue. Increased estrogen + progesterone levels
51
Luteal phase
Endometrium becomes even thicker. Coincides with formation of corpus luteum
52
Ischemia phase
Oocytes is not fertilized. Degeneration of luteum. Endometrial lining begins to breakdown
53
What is the most common site for fertilization?
Ampulla
54
When does fertilization occur?
12 hours after ovulation
55
Cleavage
Series of mitotic divisions of the zygote
56
Blastula
Zygote cytoplasm cleaved to form blastula
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What is a morula?
An inner cell mass + outer cell mass formed from blastomeres
58
Blastocyte
Forms when fluid secreted within the morula forms a cavity
59
Trophoblast
Outer cell layer of blastocyte. Forms into the placenta
60
Embryoblast
Inner cell mass of blastocyte
61
Monozygotic/monoovular
1 fertilized egg splits into 2 developing zygotes. Identical twins, same sex
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Dizygotic/polyovular
2 sperm fertilize 2 ova. No identical twins
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Triploidy
3 pronuclei within 1 zygote
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Blastogenesis
3 days after fertilization morula forms + enters uterus. Cavity forms into morula converting it into the blastocyte
65
Zona pellucida functions
Prevents premature implantation
66
“Hatching”
Zona pellucida opens allowing blastocyst to implant
67
Embryoblast
Inner cells of blastocyst
68
Trophoblast
Outer cells of blastocyst. Engulfs + destroy cells of uterine lining creating blood pools
69
Early pregnancy factor (EPF)
Immunosuppressant. Released by trophoblast. Used to determine pregnancy
70
Cytotrophoblast
Inner layer of trophoblast
71
Syncytiotrophoblast
Outer layer of trophoblast. Multinucleated protoplasmic mass. Hydrolytic enzymes. Secretes human chorionic gonadotropin
72
What does human chorionic gonadotropin do?
Stimulates corpus luteum to produce progesterone
73
What is the most common site of implantation in ectopic pregnancy?
fallopian tube
74
Embryoblast differentiation
Inner cell mass subdivides into the bilaminar disc
75
What does the epiblast form?
The embryo + extra-embryonic epithelial membrane
76
What does the hypoblast form?
The primary yolk sac
77
Day 8 after implantation: syncytiotrophoblast
WRITE OUT PROCESS IN PICTURES (END OF PWRPNT 2).
78
Where does extrauterine implantation occur?
Tubes, abdominal cavity,
79
Abortion
Premature stoppage of development + expulsion
80
Threatened abortion
Bleeding, possible abortion. 25% pregnancy complications
81
In threatened abortion, what percent of people do abort?
50%
82
Spontaneous abortion
Natural occurrence before 20 weeks. Most common during 3rd week
83
In threatened abortion, what percent of people do abort?
25-30%
84
Habitual abortion
Spontaneous expulsion of embryo in 3 or more consecutive pregnancies
85
Induced abortion
Birth that is medically induced before 20 weeks
86
Complete abortion
Everything is expelled (fetus + fetus membranes)
87
Missed abortion
Retention of concepts in the uterus after death of the embryo
88
Intrauterine fetal demise
Death of fetus after 20 weeks. AKA still birth
89
Trilaminar disc
Forms in week 3
90
Gastrulation
Process where 3 germ layers are established in the embryo
91
what does the ectoderm become?
Becomes the epidermis, CNS/PNS + many connective tissues of head
92
what does the mesoderm become?
Becomes skeletal muscle, blood cells, smooth muscle, serosal linings + most of cardiovascular system. All connective tissue in TRUNK ONLY
93
what does the endoderm become?
Becomes epithelial linings of respiratory + alimentary tract, pancreas + liver
94
What does the endoderm, ectoderm, + mesoderm form from?
Epiblast
95
Primitive streak
Thickened linear band of epiblast appears. Creates craniocaudal axis
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Functions of notochord
Provides structure, skeletal foundation of vertebral column, forms the neural tube
97
Cloacal membrane
Caudal to primitive streak + site of future anus
98
What are the layers in the oropharyngeal membrane?
Ectoderm + endoderm
99
Oropharyngeal membrane
Becomes the mouth
100
Where do you only find endoderm + ectoderm?
Oropharyngeal membrane, median plane (cranial to primitive node), cloacal membrane
101
Neural induction
Signals from the notochord telling ectoderm to become nervous system
102
Formation of neural tube
Neural plate folds to become the neural crest. Neural crest closes off to form neural tube
103
Closure of the neural tube
Closes cranially first, then caudally
104
Step by step of neurulation
1. Notochord
2. Neural plate
3. Neural groove
4. Neural tube
5. Neural crest cells
105
Neural crest cells
Migratory cells. Give rise to spinal ganglia + ganglia of ANS. Becomes neurolemma (Schwann cells)
106
How many somites are there in an embryo?
42-44
107
What 3 categories do the somites develop into?
sclerotome, myotome, + dermatome
108
What does the sclerotome become?
Vertebrae + ribs (axial skeleton)
109
What does the myotome become?
Muscles
110
What does the dermatome become?
The skin
111
What is the placenta?
Primary site of nutrient + gas exchange between mother + fetus
112
Fetal part - placenta
Develops from chorionic sac (EEMD)
113
Maternal part - placenta
Derived from the endometrium
114
Functions of maternal placenta
Protection, nutrition, respiration, excretion, + hormone production
