Chapter 2 Flashcards
how many chromosomes are there?
22 matching chromosomes, the 23rd pair determines the sex
What is a karyotype?
Pictorial representation of 23 pairs of chromosomes
What is mitosis?
Process of DNA duplication, then splitting
What is meiosis?
Cell division that forms the eggs and sperm
What is the genetic difference between males and females?
Males: XY
Females: XX
What is a genotype?
Persons genetic material
What is a phenotype?
Observable characteristics
What is the dominant and recessive genes principle?
Our gene of a pair exerts its effects (Dominant) override the potential and influence of the other gene (recessive)
Phenylketonuria (PKU)
Caused by two recessive genes, metabolic disorder, inability to break down phenyalanine
Monozygotic twins
(identical) one zygote with same genetic code
Dizygotic twins
Two separate zygotes; different genetic codes (fraternal)
Down syndrome
Caused by an extra copy of chromosome 21. risk rises with age
Klinefelter syndrome
(XXY), underdeveloped testes, enlarged breasts
Fragile X syndrome
abnormality in the X chromosomes, which becomes constricted and often breaks. intellectual disabilities, learning disabilities
Turner syndrome
Female X chromosome is missing. intellectual disabilities, sexual underdevelopment, web neck
Sickle cell anemia
Impairs functioning of the body red blood cells. Recessive gene, most common in African Americans
Germinal Period
Conception - 2 weeks
24 hours after conception - one cell called the zygote. 1 week it is called the blastula, implantation to uterine wall occurs
Embryonic period
week 2 - 8. Mass of cells now called an embryo. 14-18 days after conception neural tube forms. organs being to develop
Fetal period
Week 9 until birth. now called the fetus, muscles develop and bones Harden. fine tuning of major organs
What is a zygote?
a single cell formed 24 hours after conception
What is a blastula?
A ball of cells that will eventually turn into the embryo, 1 week in
What is the trophoblast?
outer cells, develop into the life support system
What is the blastocyst?
Inner cells that develop into the baby
What is the neural tube?
future brain and spinal cord
What develops in week 2-3?
Central nervous system, eyes
What develops in week 4?
Heart, nose, mouth, ears
What develops in week 5?
Arms, legs
What develops in week 6?
Fingers, toes
Alcohol as a teratogen
it takes a lot of oxygen to metabolize alcohol out of your system, so it is taking oxygen away from the baby. it also interferes with cell duplication and production of neurons in the brain
Fetal alcohol syndrome
small head, small eyes, flattened face and nose, brain abnormalities, heart defects, defective joints and limbs
caffeine as a teratogen
mixed results on it it is a tetrogen, FDA recommends no more than 3 cups her day
Nicotine as a teratogen
Nicotine is transmitted to the fetuses bloodstream. it impairs oxygen and nutrients to fetus; low birth weight,, miscarriage, SIDS, ADHD
Cocaine as a teratogen effects on baby
Reduced birth weight and head circumference, lowers arousal and quality reflexes, poor self regulation and emotional bonding, can attach itself to sperm
Marijuana as a teratogen
More research needed; stillbirth, low birth weight, lower intelligence
Heroin as a teratogen effects on baby
Behavior problems at birth, withdrawal symptoms
HIV as a teratogen
Mother can affect the baby through placenta, during delivery, and through breast feeding
Stress as a teratogen
Cortisol is the stress hormone, it alters the functionality of placenta. interfere with brain development, impaired cognitive development. emotional problems, conduct disorder, ADHA
Thalidomide tragedy
Mild tranquilizer used to treat morning sickness cause over 7 thousand babies to be bown with birth defects
Syphilis
Damages organs that are already damaged, Blindess, CNS damage, can’t cross the placenta in early months
toxoplasmosis
Caused by a parasite found in red meat and cat feces. causes eye and brain damage
What are the stages of birth?
Uterine contractions get closer together as cervix opens, babies head starts to move through the cervix and the birth canal, afterbirth is the third stage when the placenta and umbilical cord are detached
What is the Apgar score?
Assessment of the newborns heath at 1 to 5 minutes after birth
What is the postpartum period?
the period after childbirth when the mother adjusts both physically and psychologically to the process of childbirth. lasts about 6 weeks
What is the difference between postpartum blues and postpartum depression?
Postpartum blues may come and go, and usually goes away after 1 to 2 weeks. Postpartum depression includes major depressive episodes that typically occur about 4 weeks after delivery
