. An index of physiology. lls known asthe blastodermic membrane, which is afterwards divi-ded into layers of cells from which the embryon —The membrane enclosing the embryon isALLANTOIS.—called the amnion ; that surroundingthe amnion, the allantois or chorion. The fluid withinAMMIOTIC FLUID,_the amnion is termed theUMBILICAL CORD.—amniotic fluid. The umbilicalcord is the pedicle which connects the embryon withthat portion of the chorion which enters into the con-PLACENTA.—struction of the placenta. The pla- I 20 GENERA TIOM. centa is the organ by which the foetus derives itsnouris
. An index of physiology. lls known asthe blastodermic membrane, which is afterwards divi-ded into layers of cells from which the embryon —The membrane enclosing the embryon isALLANTOIS.—called the amnion ; that surroundingthe amnion, the allantois or chorion. The fluid withinAMMIOTIC FLUID,_the amnion is termed theUMBILICAL CORD.—amniotic fluid. The umbilicalcord is the pedicle which connects the embryon withthat portion of the chorion which enters into the con-PLACENTA.—struction of the placenta. The pla- I 20 GENERA TIOM. centa is the organ by which the foetus derives itsnourishment, and is composed of a maternal portionfrom the mucous membrane of the uterus, and a foetalportion from the vascular part of the chorion. TheFOETUS.—embryon is called the foetus at the fourthmonth. During gestation the uterus is enlarged butreturns to normal size after delivery. The duration ofpregnancy is two hundred and sixty to three hundreddays. Parturition is the process by which the foetus SLEEP AND DEATH. SLEEP.—One-third of our existence is passed insleep, and in it the functions of the body are greatlymodified. Sleep is more important in infancy andyouth, than in adult life and old age. During sleepthe brain is in a condition of absolute repose. Sleepis the result of a diminution of the supply of the bloodto the brain. DREAMS.—Dreams are automatic actions of thebrain originating from impressions received from ex-ternal sounds, while going to sleep or waking, or fromimpressions previously made upon the registeringganglia of the brain. DEATH.—Any thing which interferes with thefunctional activity of the system in the processes whichrepair its constant waste, will result in the phenom-enon called death, after which the organism decaysand the products of its decomposition are appropriatedby the vegetable kingdom, 131 TABLE OF SPECIFIC GRAVITIES. Name. Specific Gravity. Sweat. 1004. Saliva. 1005. Gastric Juice. 1005. Aqueous humor. 1005. Vi
Size: 2950px × 847px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, bookidindexofphysi, bookyear1881
