1. 髓质：角蛋白质的链状结构,使头发具有可伸缩的特性,不易被拉断. 但头发湿的时候较为脆弱,不当牵拉,容易造成损伤. 皮质内,含有具有凝结力和左右头发色质的黑色素. 毛髓质(MEDULLA)位于头发的中心部位,中间是空心的孔状结构,里面含有空气.
2. 延脑：(
1) 延脑(medulla) 延脑居于脑的最下部位,与脊髓相连;其主要功能为控制呼吸、心跳、消化等. (
2) 脑桥(pons) 脑桥位居中脑与延脑之间. 脑桥的白质神经纤维,通到小脑皮质,可将神经冲动自小脑一半球传至另一半球,使之发挥协调身体两侧肌肉活动之功能.
3. 延髓：1.延髓(medulla)延髓居于脑的最下部,与脊髓相连;其主要功能为控制呼吸、心跳、消化等. 2.脑桥(pons)脑桥位于中脑与延脑之间. 脑桥的白质神经纤维,通到小脑皮质,可将神经冲动自小脑一半球传至另一半球,使之发挥协调身体两侧肌肉活动的功能.
noun
1. the inner part of an organ or structure in plant or animal
2. lower or hindmost part of the brain
continuous with spinal cord
(`bulb' is an old term for medulla oblongata)
e.g. the medulla oblongata is the most vital part of the brain because it contains centers controlling breathing and heart functioning
Synonym: medulla oblongatabulb
3. a white fatty substance that forms a medullary sheath around the axis cylinder of some nerve fibers