Which period begins with fertilization and ends with implantation quizlet?
Ovum- germinal stage period. Period of the zygote- genetics. First two weeks of pregnancy- beginning with fertilization and ending with implantation of the blastocyst in the uterine lining. An estimated 60% of all developing organisms fail to grow or implant properly and thus do not survive the germinal period.
What period lasts from fertilization to implantation?
About 6 days after fertilization, the blastocyst attaches to the lining of the uterus, usually near the top. This process, called implantation, is completed by day 9 or 10.
Which prenatal period begins at conception and ends at the implantation in the uterus?
The Germinal Period (Weeks 1-2) The germinal period (about 14 days in length) lasts from conception to implantation of the zygote (fertilized egg) in the lining of the uterus.
What is the first critical period after fertilization and implantation?
Germinal Stage Just a few hours after conception, the single-celled zygote begins making a journey down the fallopian tube to the uterus. Cell division begins approximately 24 to 36 hours after conception.
Where does fertilization and implantation occur?
During fertilization, the sperm and egg unite in one of the fallopian tubes to form a zygote. Then the zygote travels down the fallopian tube, where it becomes a morula. Once it reaches the uterus, the morula becomes a blastocyst. The blastocyst then burrows into the uterine lining — a process called implantation.
What are the 4 stages of implantation?
After an Embryo Transfer Day 1: The blastocyst begins to hatch out of its shell. Day 2: The blastocyst continues to hatch out of its shell and begins to attach itself to the uterus. Day 3: The blastocyst attaches deeper into the uterine lining, beginning implantation. Day 4: Implantation continues.
What is the first stage of fertilization in a pregnancy called?
The fertilized egg (zygote) divides repeatedly as it moves down the fallopian tube to the uterus. First, the zygote becomes a solid ball of cells. Then it becomes a hollow ball of cells called a blastocyst.
At which stage implantation occurs?
Implantation begins with apposition of the blastocyst at the uterine epithelium, generally about 2-4 days after the morula enters the uterine cavity. The implantation site in the human uterus is usually in the upper and posterior wall in the midsagittal plane.
What is the period between Fertilisation and birth called?
Gestation is the period of time between conception and birth. During this time, the baby grows and develops inside the mother's womb. Gestational age is the common term used during pregnancy to describe how far along the pregnancy is.
What are the 3 stages of pregnancy?
Pregnancy the three trimestersFirst Trimester (0 to 13 Weeks) The first trimester is the most crucial to your baby's development. ... Second Trimester (14 to 26 Weeks) ... Third Trimester (27 to 40 Weeks)
What happens in the first week of fertilization?
Important events that occur during the first week of human embryonic development include gamete approximation, contact and fusion of gametes, fertilization, mitotic cleavage of the blastomere, morula formation, blastocyst formation, and implantation of the blastocyst.
What is the critical period in pregnancy?
In general, major defects of the body and internal organs are more likely to occur between 3 to 12 embryo / fetal weeks. This is the same as 5 to 14 gestational weeks (weeks since the first day of your last period). This is also referred to as the first trimester.
What week is most critical in pregnancy?
The fetus is most vulnerable during the first 12 weeks. During this period of time, all of the major organs and body systems are forming and can be damaged if the fetus is exposed to drugs, infectious agents, radiation, certain medications, tobacco and toxic substances.
What is the most critical period of fetal development?
The embryonic period is the most critical period of development because of the formation of internal and external structures.
What is formed first after implantation?
Fertilization and implantation During fertilization, the sperm and egg unite in one of the fallopian tubes to form a zygote. Then the zygote travels down the fallopian tube, where it becomes a morula. Once it reaches the uterus, the morula becomes a blastocyst.
When does implantation occur?
Around day 8 or 9 after fertilization, implantation begins. Implantation is the process in which a blastocyst becomes embedded in the endometrium of the uterus (see Figure 23.2. 5 ). Implantation is triggered by contact between the blastocyst and endometrium. In response to this contact, trophoblast cells start to proliferate. The trophoblast cells start secreting enzymes that digest the mucosa covering the endometrium. These changes allow finger-like projections (called villi) of the trophoblast to penetrate into the endometrium. The projections pull the blastocyst — now called an embryo — into the endometrium until it is fully covered by endometrial epithelium.
Where does the germinal stage of human development begin?
Figure 23.2. 2: The germinal stage of human development begins with fertilization in a Fallopian tube and ends with implantation in the uterus.
How long does the germinal stage last?
The germinal stage lasts a total of eight to nine days. It begins in a Fallopian tube when an ovum is fertilized by a sperm to form a zygote (day 0). The germinal stage continues as the zygote undergoes several initial cell divisions to form a solid ball of cells called a morula (days 3-4).
What is the outer layer of the blastocyst?
The trophoblast is the outer cell layer of the blastocyst. Trophoblast cells will implant in the uterus and eventually develop into the placenta and other embryonic tissues. The blastocoele is a cavity formed by the migration of embryoblast cells to one pole of the blastocyst.
What is the process of changing the morula into a blastocyst?
Blastulation. Blastulation is the process of changing the morula into a blastocyst. It occurs from roughly day 5 to day 7 after fertilization. During blastulation, the morula changes from a solid ball of undifferentiated cells into a fluid-filled ball of differentiated cells, as shown in Figure 23.2. 4.
How many cells are in a morula after fertilization?
Figure 23.2. 4: This image shows a morula consisting of eight cells on day 4 after fertilization. The image also shows a blastocyst consists of two types of differentiated cells (inner cell mass and trophoblast) and a fluid-filled cavity (blastocoele).
What are the parts of a blastocyst?
The major parts of the fully formed blastocyst are the embryoblast, trophoblast, and blastocoele. The embryoblast (inner cell mass) consists of a mass of cells inside the blastocyst. These cells will eventually develop into the embryo. The trophoblast is the outer cell layer of the blastocyst.
How long does it take for implantation bleeding to happen?
Timing of implantation bleeding. The 2-week waiting time from ovulation to the next menstrual period can be pretty frustrating if you’re hoping to be pregnant. Interpreting the signs correctly can be tricky, but luckily, sometimes timing — in addition to the symptoms above — can help you pinpoint what’s going on.
When do you get your period?
If your body follows a 28-day menstrual cycle, you won’t get your period until after day 28. So, if you’re bleeding earlier and lighter than normal, there’s a good chance it’s implantation bleeding, not your period.
How soon after conception can you test for pregnancy?
A blood pregnancy test — administered at a doctor’s office — can detect pregnancy as soon as 11 days after conception. Remember, though, that hCG isn’t produced until after implantation, so testing for pregnancy at the first sign of implantation bleeding is likely to result in a negative result.
What happens when the placenta detaches from the original site of implantation?
Subchorionic hemorrhage. This happens when the placenta detaches from the original site of implantation.
What does it mean when your period starts off light?
Your period may start off light, but the flow gets stronger. Cramping. Cramping that signals implantation is usually light and short-lived. Cramping that comes from your period is usually more intense and lasts longer. Every woman has her own pain threshold: You know your body best, so listen to it.
Why does my cervix bleed during pregnancy?
When the bleeding is light, it may be caused by pretty simple things. For example, your cervix is more sensitive and developing additional blood vessels, so sex or a pelvic exam can cause bleeding.
How long does sperm live in the body?
The egg itself is only viable for about 24 hours after being released, but sperm can live inside your body for 3 to 5 days. It’s hard to know exactly when fertilization occurs, but the fertilization window is likely the 6 days sandwiched around ovulation.
How long does it take for a baby to be implantation?
According to Dr. Nivin Todd on WebMD, implantation happens 3 to 4 days after fertilization. Signs of implantation such as light spotting and cramping can happen when this occurs. 1. According to the American Pregnancy Association, the signs of implantation occur just before your next period.
When does the cervix release an egg?
In order to get pregnant, your cervix releases an egg around about the middle of your menstrual cycle. At this time, it’s natural to see an increase in sticky white discharge and other signs of ovulation. Only when a sperm lives long enough to make its way to the egg and fertilizes it, can a pregnancy happen.
What does it mean when you feel tired after implantation?
13. Fatigue is an early sign of pregnancy and implantation. Very soon after implantation and at the very start of pregnancy, you may begin to feel fatigued. According to Dr. Tina Pagano on WebMD, the change in hormone levels takes a toll on your body and you will feel more tired than usual.
What does implantation bleeding look like?
One of the earliest signs of pregnancy is implantation bleeding which looks like light spotting near the time of your period. Advertisement. Dr. Yvonne Tobah from the Mayo Clinic says that implantation bleeding happens when the fertilized egg embeds itself in the uterine lining.
How do you know if you are pregnant?
If you are looking for early symptoms of pregnancy, it is possible to spot the first signs of implantation before your missed period. The earliest signs of implantation like implantation bleeding and cramps, tender breasts, and increased jelly-like discharge can also resemble the start of your period. So, if you want to know if you are pregnant ...
What happens if you miss your period?
These are some of the subtle signs that implantation has happened. Of course, if you miss your period, then there is a good chance that you are pregnant. In this article, you will learn about the signs of implantation and what to look out for in the early stages of pregnancy before a missed period. Advertisement.
When do women feel bloated?
It’s not uncommon for women who are in their first or second week of pregnancy to feel bloated.
What is the age period?
Age Period. Description. Prenatal. Starts at conception, continues through implantation in the uterine wall by the embryo, and ends at birth. Infancy and Toddlerhood. Starts at birth and continues to two years of age. Early Childhood. Starts at two years of age until six years of age. Middle and Late Childhood.
What is the term for a period of dramatic physical change marked by an overall growth spurt and sexual maturation?
Adolescence: Adolescence is a period of dramatic physical change marked by an overall growth spurt and sexual maturation, known as puberty.
What is the transitional period between the end of adolescence and before individuals acquire all the benchmarks?
Emerging Adulthood: The period of emerging adulthood is a transitional time between the end of adolescence and before individuals acquire all the benchmarks of adulthood. Continued identity exploration and preparation for full independence from parents are demonstrated.
What is the term for the years that follow toddlerhood?
Early Childhood: This period is also referred to as the preschool years and consists of the years which follow toddlerhood and precede formal schooling. As a two to six-year-old, the child is busy learning language, is gaining a sense of self and greater independence, and is beginning to learn the workings of the physical world.
What is the primary concern of prenatal development?
All of the major structures of the body are forming and the health of the mother is of primary concern. Understanding nutrition, teratogens (or environmental factors that can lead to birth defects), and labor and delivery are primary concerns.
What is the age of late adulthood?
Late Adulthood: Late adulthood is sometimes subdivided into two categories: The young-old who are from 65-84 years and the oldest-old who are 85 years and older.
What is the difference between middle adulthood and early adulthood?
Early Adulthood: The twenties and thirties are identified as early adulthood. Intimate relationships, establishing families, and work are primary concerns at this stage of life. Middle Adulthood: The forties through the mid-sixties is referred to as middle adulthood.
