The fact that blood and bones belong with connective tissues is dealt with the most of Japanese textbooks of biology “Seibutu I B” for senior high school student. It is important to observe the relation between blood and bones in the biology class, because this fact is an essential knowledge for understanding of the medical issues such as the marrow transplant and the pollution victims.
The purpose of this study is to show that an observation on the bone marrow from chickens helps students to understand this fact. Five brands of Chicken bones, or “wing sticks” as they are called in butcher were examined to see if they are usable for this purpose and one brand was found to be usable as material.
The procedure for observing blood cells in chicken bone marrow was as follows: Fluid from the bone marrow was dropped on a slide glass, spread with a cover glass and dried out in a room. It was fixed with methyl alcohol and stained with Giemsa-solution. After the specimen was washed with water, it was covered with a cover glass. Students observed the specimen under the microscope. The material and method were easily dealt with by the students. They wereable to observe many red blood cells and a few white blood cells.
Zebrina pendula, a foliage plant which belongs to a family Commelinaceae, shoots out branches in summer, and its bract leaves* differentiate from a shoot apex in early autumn. We paid a special attention into the relationship between alternate phyllotaxis and inflorescence of Zebrina pendula.
First, it is possible to observe the mitotic cell division in the primordia of a shoot apex, if we take the base of the smallest leaf according to the alternate phyllotaxis before the bract leaves* are differentiated in late August. In addition, we clarified that the primordia of young buds are formed alternately in the similar manner to the young leaves, after bract leaves are differentiated in early September. Here we called the primitive buds series on the left hand l1, l2, l3,……ln and those on the right hand rl, r2, r3……rn, and also, we called the matured bud series on the left L1, L2 and those on the right R1, R2.
Thus, the authors found an effective method to observe the earliest developing process of reproductive cells including meiotic cell division by searching young buds in the swelling base of bract leaves before flowers are in bloom.
* : Two leaves covered buds in a shoot apex.