SC.912.L.16.13 Adrian Alvarez P.2

DNA DNA stores and transmits genetic information. Genes are sets of instructions encoded in the structure of DNA. Genetic information is passed from generation to generation by DNA in all organisms and accounts for similarities in related individuals.

Human Reproductive System

Fertilization Development Development begins with fertilization when and egg and a sperm join together to form a zygote. The zygote then under goes mitosis and becomes a hollow ball of cells called blastocyst which then attaches to the uterus wall. This process is known as implantation Takes on Average 9 months but are premature and delayed child birth.

(Continue) After continued development, gastrulation occurs and results in the formation of three cell layers, ectoderm, mesoderm, and endoderm, the ectoderm and endoderm form first then the mesoderm produced by cell migration. Endoderm cells will develop into the skin and nervous system Mesoderm cells will differentiate and form bones, muscle, blood cells, and gonads

(Continue) neuralation is the first step in developing the nervous system. After gastrulation is complete a block of mesoderm cells differentiates into a notochord. As the notochord develops the ectoderm cellsnear it thicken and form the neural plate. The raised edges form the neural folds and the neural crest. The neural folds gradually come together to form the neural tube which is where the spinal cord and the brain will develop. They also become nerve cells, skin pigment cells .

Trimester of pregnancy Major changes in the 1st Trimester – body structure and organ systems develop Major changes in the 2nd Trimester – movement in the womb Major changes in the 3rd Trimester – increase in the size of the uterus

Child Development