Heredity
the passing on or transmission of biological characteristics from parent to child
chromosomes
tiny structures found within almost every cell, carry info about characteristics you will inherit; made up of a chemical substance known as DNA
gene
section of a chromosome that determines a single trait such as earlobe shape
conception
united egg and sperm called zygote divides by mitosis during its journey through fallopian tubs to uterus; journey takes 36 hours
implantation
when zygote arrives in uterus it floats freely for a few days where it divides mitotically while waiting for uterine lining to prepare by progesterone
blastocyst
fertilized cell, now single layered sphere of cells enclosing a fluid filled cavity
implantation
attachment to wall of the uterus
embryo
after implantation is known as embryo, occurs in 2nd month after conception
placenta
attachment site; thin tissue seperating material and fetal blood and is filter between the mothers blood and teh embryos blood
umbilical cord
developed after 25 days is the embryos lifeline; blood vessels carry nutrients and oxygen from the placenta to embryo also takes waste from embryo to placenta
fetus
new name after the embryo is 1.2 inches and has features like eyes and hands
1st trimester (baby)
external genital organs are developed; fingernails and toenails appear; eyelids are formed; fetal movement increases; arms and legs fully formed; heart function at tenth week
2nd trimester (baby)
fetus is 11 inches long and 1.5 lbs; fetus kicks moves and turns from side to side; sense organs function; fetus develops reflexes like swallowing and sucking; brain undergo its most important period of growth from 5th month on; fingerprints and toeprints
3rd Trimester (baby)
fetus sees and hears; brain develops; kidneys and lungs continue to nature; by 36th week head may engage and drop into pelvic area;bones of skull remain soft to pass through birth canal; fetus can suck its thumb and cry; 38-40 weeks lungs are 100% mature;
1st Trimester (mother)
morning sickness; nausea and vomit caused by abnormal changes only last few weeks; increase breast size and tenderness; frequent urination; sleepiness; abdomen more round but unnoticable
2nd Trimester (mother)
abdomen swells; mother feels moving fetus; uterus pushes against digestive tract causes constipation and indegestion; fluid leaks from breasts
3rd Trimester (mother)
most women gain 25-35 lbs; movement can be seen and felt in abdomen; indegestion and frequent urination; irregular contractions begin as uterus prepares for labor; abdomen hardens and protrudes as fetus head goes lower in uterus.