Chapter 12 Quiz - Exam 4 Flashcards
Following semen deposition, sperm are exposed to a series of different environments which alter their numbers and function
Sperm transport
Prevent microorganisms from entering the female reproductive tract
Neutrophils
Phagocytize sperm
Neutrophils
1 neutrophil can engulf _____ motile sperm
Several
Neutrophils can’t distinguish between ___ or _____ ______
Live or dead sperm
What releases a bunch of neutrophils once sperm are released into the female tract
Uterine mucosa
2 types of sperm transport
Rapid
Sustained
Sperma transported to oviduct in minutes
Non-viable sperm
Rapid sperm transport
Viable sperm
Sperm are transported to oviducts in a trickle-like fashion from sperm reservoirs in the cervix, uterus, and UTJ
Sustained sperm transport
____ of spermatozoa deposited in the uterus of a cow via artificial insemination are lost to the exterior of the reproductive tract within ___ hours after deposition
60%
12
Transport out of the reproductive tract
Retrograde transport
Mating occurs during the
Follicular phase - high estradiol
What causes an increased tone and motility of the uterus and oviduct
Prostaglandins
What if the female reproductive tract propel sperm in an anterior and posterior direction
Peristaltic contractions
The fluid secreted from the ____ ________ into the lumen are the vehicle for sperm transport
Uterine endometrium
What can advance the time of ovulation in gilts
Component in boar seminal plasma - protein?
Can add ______ or _________ to the seminal plasma to increase contractility of the uterus and oviduct
Estradiol
Prostaglandins
If you give rabbits an activator of _____ ______ ___________, fertilization rates with a fixed number of sperm will increase
Smooth muscle contractility
_____ acts as a barrier and reservoir to sperm in the cow
Cervix
The cervix produces 2 types of mucus:
Sialomucin
Sulfomucin
Type of mucus: low viscosity
Sialomucin
Type of mucus: located in the cervical crypts
Sialomucin
Type of cervix: sperm swim into it - creates privileged pathways
Sialomucin
Type of mucus: where motility of sperm is important
Weed out non-motile spermatids at level of the cervix in the cow
Sialomucin
Type of mucus: very viscous
Sulfomucin
Type of mucus: located on the apical surfaces of the cervical folds
Sulfomucin
Type of mucus: sperm are washed out of the reproductive tract
Sulfomucin
The changes that sperm undergo during the minimum period of time that sperm must reside in the female reproductive tract in order for maximal fertility to be achieved
Capacitation
A series of biochemical changes in sperm
Capacitation
Site of Capacitation: may begin as sperm move through the cervix
Bull
Site of capacitation: must begin in uterus since sperm are deposited there
Stallion
Not all sperm are capacitated at the
Same rate
Series of specific interaction to one between sperm and oocyte
Fertilization
Sperm change from a linear, progressive movement to a frenzied, dancing motion that isn’t linear and is localized to a small area
Hyperactive motility
Occurs in oviduct
Facilitates sperm-oocyte contact
Hyperactivity motility
Zona binding proteins must be exposed by ________ before binding can occur
Capacitation
Sperm have specific proteins on membrane surface overlying acrosome which bind specifically to proteins on the Zona pellucida
Binding to the Zona pellucida of the oocyte
Zona pellucida consists of 3 glycoproteins:
Zona protein -1
Zona protein -2
Zona protein -3
Structural proteins which help maintain the structural integrity of the zona pellucida
Zona protein-1
Zona protein-2
Very much like a receptor for a hormone
Binds proteins found on the sperm plasma membrane
Zona protein-3
Sperm binding to oocyte requires _____ to _______ ZP3 molecules
10,0000 to 50,000
Sperm have 2 binding sites:
Zona binding region
Acrosome reaction promoting region
Causes sperm to adhere to the Zona pellucida
Zona binding region
Binding between this region and ZP3 of the oocyte and this region activates second messenger systems which initiate the acrosome reaction
Acrosome reaction promoting region
2 purposes of acrosome reaction
Enables sperm to penetrate the Zona pellucida
Exposes equatorial segment so it can later fuse with plasma membrane of the oocyte
What begins when plasma membrane of spermatozoa forms multiple fusion sites with the outer acrosomal membrane
Acrosome reaction
When plasma membrane of spermatozoa forms multiple fusion sites with the outer acrosomal membrane
Vesiculation
Acrosomal contents are dispersed, leaving the sperm nucleus’s surrounded by the _____ _____ ______ and the _____ _______ exposed
Inner acrosomal membrane
Equatorial segment
Acrosomal contents include
Acrosin
Proacrosin
Hydrolyzes Zona proteins and enhances sperm’s ability to bind to Zona pellucida
Acrosin
Inactive form of acrosin is
Proacrosin
What has a strong affinity for the Zona pellucida
Proacrosin
Aids in binding sperm to the Zona pellucida
Proacrosin
As the acrosome reaction proceeds, Proacrosin is converted into _____ which allows the sperm to penetrate the Zona pellucida and make its way through
Acrosin
What action of sperm helps push its way through the hole caused by release of Acrosin
Flagellar action of sperm
The hole produced by the Acrosin is only the diameter of the ______ so that the integrity of the Zona pellucida remains intact
Sperm
Important to protect and keep the ______ together
Embryo
Speed of penetration of Zona pellucida
Rapid
A few minutes
Once sperm has passed through the Zona pellucida, it enters the
Perivitelline space
Where must sperm bind to the plasma membrane of the oocyte
Perivitelline space
Sperm settles down on a bed of _________ which are part of the oocyte plasma membrane
Microvilli
The _______ __________ of the oocyte and the _______ _________ of the sperm fuse
Plasma membrane
Equatorial segment
What brings about the fusion of the plasma membrane of the oocyte and the equatorial segment of the sperm
A fusion protein
What requires vesiculation and release of acrosomal contents to become active
A fusion protein
Fertilization with more than 1 sperm
Polyspermy
The ______ undergoes a number of changes to prevent polyspermy
Oocyte
An abnormal chromosomal complement
Polyploidy
What would lead to an abnormal chromosomal complement (polyploidy)
Polyspermy
Cortical granules which appear during the 1st and 2nd meiosis are present at the
Periphery of the oocyte cytoplasm
What are just inside of the plasma membrane
Small, dense granules
Small, dense cortical granules undergo ________ and release their contents into the Perivitelline spate upon sperm binding to the plasma membrane
Exocytosis
Cortical granules contain
Mucopolysaccharides
Proteases
Plasminogen activator
Acid phosphatase
Peroxidase
2 major changes from release of cortical granule contents
Zona block
Vitelline block
Type of block: slow
Zona block
Zona pellucida changes biochemically so more sperm can’t penetrate it
Zona block
Type of block: fast
Vitelline block
Prevents additional sperm from binding to the oocyte plasma membrane
Vitelline block
Oocyte plasma membrane
Vitelline membrane
T/F: some species have both a Zona and Vitelline block whereas others have one or the other
True
A process whereby the male inseminated the female and spermatozoa remain viable in the female tract for a sustained period of time
Delayed fertilization
When a rooster inseminates a hen she can lay fertile eggs for over ___ days
20
Sperm are stored in special
Utero-vaginal glands
The fertilizing life of bat sperm is reported to range from ___ to ____ days
68 to 198
Snakes are reported to store sperm that are fertile for up to ___ years
6
The bifurcation of the glans penis of the opossum led to the widespread Appalachian folk belief that opossums mated through the ____, with one fork of the glans penis penetrating each _____
Nose
Nostril
Male mammals deliver sperm to the female in
Seminal plasma
I some cephalopods the male deposits the spermatophore in the female tract or into the ______ ______, from which it can be conveniently transferred to the female tract
Buccal cavity
In some annelids, spermatophores are ________ __________, after which the spermatozoa spread throughout the female’s body before contacting eggs
Injected subcutaneously
Who typed the 1st edition of pathways to pregnancy and parturition from the author’s dictation
Cheryl Dudley