A&P Chapter 27 Online Homework
What connects the placenta to the fetus?
umbilical cord
Which reaction releases enzymes such as hyaluronidase and acrosin that allow sperm to penetrate the corona radiata of the secondary oocyte?
acrosomal reaction
Which fetal hormone initiates labor?
cortisol
What do the umbilical arteries transport?
deoxygenated blood away from the fetal heart
What does the ectoderm form?
neural plate and neural tube
Predict the possibility of an offspring with a widow's peak, a dominant inherited trait affecting the hairline, when both parents are heterozygous for the trait.
75% of the offspring will have a widow's peak.
Which of the following is NOT one of the changes that happen in the maternal body during pregnancy? A) increased hematocrit B) increased respiration rate C) increased cardiac output D) increased glomerular filtration rate
A
Which of the following is NOT an example of a trait inherited by polygenic inheritance? A) height B) blood group C) eye color D) skin color
B
Which of the following is NOT a function of amniotic fluid? A) allows the embryo freedom of movement B) maintains a constant temperature for the developing embryo C) provides nutrition for the developing embryo D) protects the embryo from trauma
C
Which of the following is NOT a period of prenatal development? A) pre-embryonic B) fetal C) neonatal D) embryonic
C
T or F: Neonatal heart rate and respiratory rate are both lower than those of adults.
False
What implants in, or attaches to, the endometrium of the uterus?
blastocyst
Labor progresses through the following three stages:
dilation, expulsion, and placental stages.
The pigment cells of the skin, cells of the adrenal medulla, and connective tissue cells are formed by this germ layer.
ectoderm
This germ layer forms the majority of the nervous system and sense organs.
ectoderm
The majority of the liver, the gallbladder, and pancreas are formed by this germ layer.
endoderm
The thyroid gland, parathyroid glands, and the thymus are formed by this germ layer.
endoderm
Which hormones stimulate the growth of alveoli in the mother's mammary gland?
estrogen and prolactin
What does gastrulation accomplish?
formation of the three germ layers
If two alleles code for the same trait (such as blond hair), they are said to be:
homozygous.
An adult heart should have a:
ligamentum arteriosum.
This germ layer forms most of the cardiovascular system
mesoderm
This germ layer forms the gonads, kidneys, and spleen of the developing embryo
mesoderm
Prolactin is to milk __________ as oxytocin is to milk __________.
production; ejection
Which hormone suppresses uterine contractions until birth?
relaxin
The endoderm gives rise to __________.
respiratory and digestive epithelium