These elements, unlike the transition elements, do not exhibit variable oxidation states, and their valence electrons are only present in their outer shell. All of these elements are solid, have a relatively high density, and are opaque. They have oxidation numbers of +3, Â±4, and -3. The Other Metals are: Aluminum Gallium Indium Tin Thallium Lead Bismuth This website is copyright Â© 1996-2012 Yinon Bentor. The 7 elements classified as other metals are located in groups 13, 14, and 15.
1 The embryo grows rapidly, and the baby's external features begin to form. 2  Your baby's brain, spinal cord, and heart begin to develop. 3  Baby's gastrointestinal tract starts to form.  It is during this time in the first trimester that the baby is most at risk for damage from things that may cause birth defects.
This photo shows a baby at 16 weeks of gestation during the second trimester of pregnancy. At this stage: Tissues including bones and muscles continue to form. The baby begins to develop translucent skin. The baby begins to form a substance called meconium, which is the first bowel movement.