The process of prenatal development occurs in three main stages. The first two weeks after conception are known as the germinal stage , the third through the eighth week is known as the embryonic period, and the time from the ninth week until birth is known as the fetal period.
What is the first stage of prenatal development called?
This union marks the beginning of the prenatal period, which in humans encompasses three distinct stages: (1) the pre-embryonic stage , the first two weeks of development, which is a period of cell division and initial differentiation (cell maturation), (2) the embryonic period, or period of organogenesis, which lasts ...
What are the stages of prenatal development in order?
There are three stages of prenatal development— germinal, embryonic, and fetal . Prenatal development is also organized into trimesters: the first trimester ends with the end of the embryonic stage, the second trimester ends at week 20, and the third trimester ends at birth.
What happens first in prenatal development?
First, the cells of the embryo (called embryonic stem cells) multiply and develop . They become the hundreds of different types of cells needed to make a whole human body. Your baby’s major organs and body parts begin to take shape. The placenta forms during the embryonic stage.
What is the first stage of prenatal development quizlet?
Prenatal development proceeds through the germinal (first 2 weeks) , embryonic (2 weeks to 2 months), and fetal stages (2 months to birth) as the zygote is differentiated into a human organism. The embryonic stage is a period of great vulnerability, as most physiological structures are being formed.
What is the second stage of prenatal development?
Embryonic Stage . The second stage of gestation, the embryonic stage, lasts from the implantation of the blastocyst on the uterine wall until approximately the eighth week of pregnancy. During this time, the embryo’s cells continue to multiply and begin to differentiate to form various body tissues and organs [3].
What is fetal stage of development?
A fetus is a prenatal human being between the embryonic stage and birth . The fetal stage extends from the beginning of the ninth week after fertilization to about 38 weeks after fertilization, which is the average time of birth. The fetal stage lasts a total of approximately 30 weeks.
What are the 5 stages of conception?
- Conception: From Egg to Embryo. ...
- Ovulation. ...
- Moving Into the Fallopian Tube. ...
- The Sperm’s Long Journey. ...
- Fertilization: Sperm Penetrates Egg. ...
- The Cells Start to Divide. ...
- Implantation. ...
- Pregnancy Hormones.
What are the 3 stages of pregnancy?
- First 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 are the developmental stages?
There are three broad stages of development: early childhood, middle childhood, and adolescence . They are defined by the primary tasks of development in each stage.
What are the 4 stages of embryonic development?
- 1.1 Fertilization.
- 1.2 Cleavage.
- 1.3 Blastulation.
- 1.4 Implantation.
- 1.5 Embryonic disc.
During which stage of prenatal development does breathing movement begin?
Fetal breathing movements begin around week 20 or 21 , and occur when contractions of the respiratory muscles cause the fetus to inhale and exhale amniotic fluid. These movements continue until birth and may help to tone the muscles in preparation for breathing after birth and are a sign of good health.
What happens in the first 4 weeks of pregnancy?
Weeks to go! In week 4 of pregnancy, your body is beginning to form the placenta and amniotic sac . Symptoms like abdominal pressure and tender breasts may appear this week, and as the cluster of cells that will soon become your baby burrows into your uterine lining, you may also spot some implantation bleeding.
What is the first and shortest stage of the prenatal?
The germinal stage of development is the first and shortest of the stages of the human lifespan.
What stage does conception begin at quizlet?
Terms in this set (20) 1st stage of prenatal developmental . Time: 2 weeks. Begins at conception when the sperm and egg cells fuse in a fallopian tube.
Which of the following correctly lists the stages of prenatal development in order from beginning to end?
Which of the following correctly lists the stages of prenatal development? Germinal, embryonic, fetal . The embryonic stage is the period from implantation until about the eighth week of development.
What is the pre embryonic stage of development?
The first 2 weeks of prenatal development are referred to as the pre-embryonic stage. A developing human is referred to as an embryo during weeks 3–8, and a fetus from the ninth week of gestation until birth.
What happens in the first 24 hours of conception?
The fertilized egg stays in the fallopian tube for about 3 to 4 days. But within 24 hours of being fertilized, it starts dividing fast into many cells . It keeps dividing as it moves slowly through the fallopian tube to the uterus. Its next job is to attach to the lining of uterus.
When does conception start in pregnancy?
Conception (when the egg is fertilized by the sperm) can take place as soon as three minutes after sex or it may take up to five days. Implantation (when the fertilized egg attaches to the uterine wall) occurs five to 10 days after fertilization—which means it can happen anywhere from five to 15 days after you had sex.
Which stage of prenatal development is the longest?
In the fetal stage , the developing human organism is called a fetus. This is the longest stage, starting in the ninth week after conception and continuing until birth.
Which of the following events occur during the first trimester of fetal development?
The spinal cord, brain, heart, and lungs grow and develop rapidly during the first trimester. In addition, the mouth, nose, eyes, ears, toes, and fingers begin to form. Your baby’s heart will begin to beat around week 6. It sometimes cannot be heard until around week 10-12.
What are the 9 stages of pregnancy?
- Amniocentesis.
- First Trimester Health.
- First Trimester Tests.
- Second Trimester Health.
- Second Trimester Tests.
- Third Trimester Health.
- Third Trimester Tests.
- Ultrasound.
What are the ages and stages of development?
Other scholars describe six stages of child development that include newborns, infants, toddlers, preschool, school age, and adolescents . Failing to reach some of the milestones may signal a developmental disability.
What are the 7 stages of development?
There are seven stages a human moves through during his or her life span. These stages include infancy, early childhood, middle childhood, adolescence, early adulthood, middle adulthood and old age .
Is 2 weeks pregnant actually 4 weeks?
Even though you likely ovulated and conceived only two weeks ago, technically, you’re considered to be four weeks along .
How does a 4 week pregnant belly feel?
Bloated stomach .
Expect a bit of bloating, particularly in your abdomen. Your uterine lining is getting a bit thicker, and the swelling means your womb is taking up more space than usual.
Which stage of pregnancy is the shortest?
In the third stage of labor, the placenta is delivered. The placenta grows in your uterus and supplies your baby with food and oxygen through the umbilical cord. This stage is the shortest and usually doesn’t take more than 20 minutes.
Can you see a baby at 5 weeks?
At this stage, the only things you’ll likely see are the yolk sac and the gestational sac . It’s possible that the sonographer might be able to point out the embryo, which at this stage is likely a tiny white curled object. Surrounding the embryo is the yolk sac, which will look like a small white circle.
During which stage of prenatal development does breathing movement begin quizlet?
19 weeks, the fetus can hear. 27 weeks , breathing movements begin in preparation for breathing outside womb. 28 weeks, rapid brain development begins and eyes open. 37 weeks, lung development almost complete.
