Exam Flashcards
Fertilization
Joining of the male and female gametes
- each gamete has 23 chromosomes; joined to form a cell with 46 chromosomes called a zygote
- Takes four days to reach the uterus
Zona pellucida
Thin layer that covers the plasma membrane of the egg
Acrasome after fertilization
Acrosome releases its enzymatic components
- the plasma membrane depolarizes, and other sperm are prevented from entering
Zygote
Resulting single cell produced by fertilization
- Moves from one cell to 16 through a process of cleavage
Cleavage
Process of cell division without cell enlargement
Morula
Once the zygote reaches 16 cells
- begins to fill with fluid
- Reaches uterus 3 to 5 days after fertilization
Blastocyst
Mass of cells with a hollow core
- Contains the embryo blast and the trophoblast
Embryo blast
Develops into the embryo
Tropho blast
Forms the outer layer and will develop into the Corion
- implants to endometrium between days five and seven
- secretes enzymes that digest the endometrium and the blast sinks into the layer
Implantation
The nestling of the blastocyst into the endometrium
- Complete by day 10 to 14
Human chorionic gonadotropin
Hormone that maintains the corpus luteum
- Secreted by the trophoblast
- maintain the secretion of oestrogen and progesterone
- function later replaced by placenta
Amniotic cavity
Space form between the inner cell mass and the trophoblast
Gastrulation
The embryonic disk forms into three layers
- Ectoderm: nervous system, epididymis
-Miso Durm: skeleton, muscles, reproductive system
-Endoderm: lining of the digestive and respiratory system systems, endocrine glands
Gastrula
Embryo that has gone through gastrulation
How does the development in organs and organ systems occur?
Growth: cell division
Morphogenesis: development of body form and structure
Differentiation: enable cells to develop particular shape and function
Neurulation
Forming of the neural tube that will develop into the brain and spinal cord
Extra embryonic membranes
Structures that support the embryo
Allantois
Forms the umbilical cord
Amnion
Fills with amniotic fluid to protect embryo from trauma and temperature changes and allows freedom of movement
Chorion
Outermost membrane informs foetal part of the placenta
Yolk sac
Produces the first blood cells and contributes to the formation of the digestive tract
Placenta
Were metabolic exchange happens
- Fully formed by 10 weeks
- Exchangers O2, nutrients, CO2, water, vitamins, and minerals, urea, antibodies, hormones, and drugs
- secretes, estrogen, progesterone and hCG
Teratogens
Environmental agents that induced developmental abnormalities
- most dangerous in the first trimester
Foetus
Nine weeks to birth
Parturition
Birthing process/labor
- begins with uterine contraction
- Positive feedback
Lactation
The secretion information of breastmilk
How do prolactin and oxytocin help with lactation?
Prolactin, is secreted after birth and milk. Production begins after a few days.
Oxytocin causes contractions in the memory lobules , releasing milk
In vitro fertilization
Immature eggs are retrieved from follicles
- eggs are combined with sperm in glassware and then inserted into the uterus or oviduct
Artificial insemination
Sperm are deposited into the uterus, not natural naturally
Surgical sterilization
The blockage of reproductive passageway
- Vasectomy/tubal ligation
- still produce eggs/sperm
Hormonal birth control
Maintain progesterone and or oestrogen
CVS and
Amniocentesis
Chronic villa sampling or sample of amniotic fluid to test foetal DNA for abnormalities
First trimester development
Blast this into embryo, continue growth, all organs are formed, mapped out limbs and organs, increase blood volume by 50%, oxygen, hard as the first organ, beats at 157 bpm, face is formed, eyes, steeping reflex
Second trimester development
Sex organs, human look, movements being controlled by brain, CNS, active, heart, regulated, hardening bones, functioning, and fully grown baby, hand before feet, preparation
Third trimester development
Development of the senses, pint of fluid every day, memory, strong movement, left/right handed, head first, hearing stimulated, hear, foetal heart, eyelashes, develops into reflexes, hiccup, 90% of time sleeping, lungs to the last organ
