Human Fertilisation and Development

At one month of pregnancy the baby is still any embryo and it is made up of two layers which will soon produce into body parts and organs. In the first two weeks of pregnancy a women isn’t actually pregnant because the women’s body is preparing for ovulation as usual. You usually ovulate (release an egg) around two weeks after the first day of your period this depends on the length of your period. Then during the third week after the first day of your last period your fertilised egg moves across the fallopian tube towards the womb. The egg starts off as a single cell but it divides multiple times. By the time the egg reaches the womb it becomes the mass of 100 cells which is known as an embryo. In the fourth week of pregnancy the embryo grows and develops in the lining of the womb. The outer cells reach out and link themselves with the mothers blood supply. The inner cells form

After embryo development, endosperm is growth to store nutrients. This happens after double fertilization, when the triploid nucleus of the ovule’s central cell divides. This causes the formation of a milky multinucleate “supercell”. This becomes multicellular after cytokinesis. Finally, when the cell walls are completed, the endosperm becomes solid.

human from usually two months after conception to birth. It defines an embryo as a human or

A blastocyst is a ball of sixteen somatic cells that contains a thin spherical wall of cells surrounding a fluid-filled center which resembles a fluid-filled balloon. There are no organs or tissues at this stage and lacks a body plan. Eventually 9 six days after conception, the blastocyst attaches to the mom so it can join

S: Page 134 is all about the embryonic period of pregnancy. The embryonic period lasts from week 3 to week 8, and it is a very important time because that is when the ectoderm, mesoderm, and endoderm are being formed. The ectoderm, mesoderm, and endoderm will later for more important oragans and body structures.

Biological development of a fetus is vary rapid and complex over the nine-month period in the womb. When both the male spermatozoon and the female ovum combine it forms what is called a zygote which holds the twenty-three pairs of chromosomes. The zygote or the embryo undergoes cell division and makes its way to the uterine wall to implant itself, this process is completed about ten days after conception. By the end of the eighth week the organ systems have formed and human characteristics can start to be noticed. From the eighth week until birth the embryo is now labeled a fetus. Quickening can occur from the sixteenth week until birth, this is where the mother can feel the fetus moving. Around the twenty-second week viability can take place, this is where the fetus can survive outside the womb. The nine-month period of being pregnant is split into different trimesters. With the different trimesters there are different abortion procedures can be used to remove the fetus.

Prenatal development is the process of rapid growth and change of a zygote to a fully formed baby that begins about 40 weeks prior to birth. It is divided into three trimesters where the first ends at the end of the embryonic stage, the second around the 20th week of pregnancy, and the third ends at birth. These trimesters do not correspond with the three stages of prenatal development known as germinal, embryonic, and fetal.

Those stages are the Germinal stage, the Embryonic stage, and the Fetal stage. The Germinal Stage is the first stage and it is a two-week period that happens after the sperm and egg cell join together to form a zygote. This process is called conception. After conception, the zygote begins to divide. This turns into into a ball of cells that moves beside the fallopian tube. This travels all the way to the uterus. This process is called implantation and it happens when the cells is placed in the wall of the uterus. This process takes about a week to complete. After the two weeks, the Embryonic stage takes place next. The embryonic stage takes two to eight weeks right after conception. At this point in the process, the ball of cells is now an embryo. In this stage, all the major organs form. The last stage of prenatal development is the Fetal stage. This last eight weeks after conception up to birth. One of the first things to take place is the sex organs begin to form. Next, the bones form, muscles form, and the fetus begins to move. The organ systems also begin to develop and the brain’s size grows. One of the last things to work independently is the respiratory and digestive

After implanted into the mother’s uterus, “All of the essential structures have been formed (both inside and outside) by the time the embryonic period comes to an end. The new title of fetus is now given to the embryo” (Roundy, 2014). Essentially, the mass of cells is now known as an embryo and the eyes, head, mouth and nose start to take shape. Blood vessels surround the embryo, leading to a very own heartbeat. The formation of upper extremities and lower extremities are developing! The sex of the baby will be determined, whether the baby will be a boy or baby girl.

Reproduction Throughout the course of history, reproduction has been a vital part of all living organisms. To most living things, reproduction is the only purpose of their existence and if they do not reproduce, they have not reached their goal in life. Humans are the first animal to break this rule. In reality, humans live to be successful and happy and this defines their life instead of reproduction.

The first trimester consists of all embryonic development and the primary month of fetal development. By the end of the third month (end of 1st trimester), the cartilage skeleton is beginning to ossify, the kidneys as well as liver are operating, teeth have formed, and determination of whether male or female can be concluded. In contrast, in the third trimester they eyes open and shut, the sucking reply evolves (numerous fetuses initiate to suck their thumbs or other fingers), and loud noses begin a startle response. The lanugo is vanished, and a layer of protective fat initiates to develop.

Due to modern medicine, there are many ways that pregnant women can now see how their fetus is growing inside them. The woman’s egg travels down the fallopian tube entering the uterus. It is fertilized by the sperm and its home for the next nine months. There is a long process before the baby arrives into the mother's arms. This is the beginning of conception and the development of the baby.

    According to parents.com, after conception, a fetus begins to develop rather quickly. In the fifth week of pregnancy, a baby’s heart begins to beat. A baby also develops three distinct layers, ectoderm, endoderm, and mesoderm. These three layers will eventually form the body systems that are necessary

First trimester: By 12 weeks of pregnancy the foetus will be fully formed. The ovum grows and develops certain important parts of the baby’s body such as spinal cord, nervous system, gastrointestinal system, heart and lungs in the first four weeks from conception. The heart starts beating and brain and other organs forms by eight weeks. At this stage, the face is formed and arms and legs start to move. The baby grows to 3 inches long and

Do you know how you were born? Do you know how you came to be? The reproductive system is the system that made that all possible. Without the reproductive system you wouldn’t have been born. In order to produce offspring, the male and female reproductive systems have to be different. Each system has different parts, problems and care. Each system have different purposes, the male reproductive system’s function is to produce sperm, while the female reproductive system’s function is to produce ova, store ova and house a fertilized egg.