prevents antibodies in the blood from getting to the germ cells
The penile urethra is enclosed by the?
The____ is/are the site(s) of sperm maturation and storage.
Which of the following hormones directly stiumlates the development of male secondary sex characteristics?
Which hormone suppresses spermatogenesis without affecting testosterone secretion?
Changes called male climacteric are a consequence of?
increased secretion of FSH and LH
In meiosis, each parent cell produces?
four haploid cells.
The most important role of meiosis in sexual reproduction is?
that it prevents the chromosome number from doubling in each generation
Male infertility (sterility) refers to?
the inability to fertilize an egg.
A sperm count any lower than ____ million sperm per mL of semen is usually associate with infertility.
20 to 25
an autonomic reflex meditated predoimantly by PARASYMPTHETIC nerve fiberes.
Blood flow is pulsatile in arteries and veins but it is steady in capillaries.
Most tissue fluid is reabsorbed by the lymphatic system.
Lung tissue receives nourishment and waste removal from the pulonary circut?
Blood filtered through the hepatic sinusoids exists the liver via the hepatic veins.
The radial artery is lateral to the ulnar artery.
The outermost wall of an arter or vein is called the ____ and in large arteries and veins contains the ____.
tunica externa; vasa vasorum
These are all possible circulatory routs from the hear except....
heart > arteries > capillary bed >vein > capillary bed > arteries > heart
The medullary ischemic reflex results in?
increased circulation to the brain
All of these increase blood pressure except?
atrial natriuretic peptide
_____ are powerful vasoconstrictors, and _____ also increases heart rate.
Epinephrine and angiotensin II, epinephrine
_____ by the capillaries at their venous end.
Ammonia is taken up.
_____ would NOT increase capillary filtration.
Obstructed venous return
_____ shock can be produced by hemorrhage, severe burns or dehydration.
Myocardial infarction can lead to ______ shock.
Pulmonary arteries have______ vlood pressure compared to systemic arteries.
There are no _____ in humans.
right and left brachiocephalic ARTERIES.
The cerebral arterial circle (circle of Willis) is?
an anastomosis surrounding the pituitary gland
The principal venous drainage of the thoracis organs is accomplished bythe way of?
the azygos system
Testosterone is a gonadotropin.
Thyroid hormone has a calorigenic effect.
Peptide hormones are synthesized by cytoplasmic ribosomes as active enzymes.
Eicosanoids are derived from steroids.
Addison disease is a consequence of a tumor of the adrenal medulla.
__ are secreted by one cell into the tissue fluid, diffuse to nearby cells in the same tissue, and stimulate their physiology.
The ___ is not an endocrine gland but it has a role in endocrine function.
Thyrotropin-releasing hormone targets the ?
anterior pituitary (adenohypophysis)
Antidiuretic hormone (ADH) targets the
The infundibulum is?
a projection of the hypothalamus in which the pituitary gland hangs
The ___ secretes several hormones that stimulate the development of lymphatic organs and regulates development and activity of T cells (white blood cells).
The ___ secrete(s) ___, which promotes Na+ and water retention.
adrenal cortex; aldosterone
These are all secreted by the pancreas except
somotropin (growth hormone)
___ is synthesized in the rough endoplasmic reticulum?
___ enters the target cell's nuclei and acts directly on the genes.
During the exhaustion stage of the general adaptation syndrome (stress response) stress overwhelms homeostasis. A characteristic of this stage is that?
energy demandands are primarily met by CARBOHYDRATE metabolisim
Eicosanoids are derived from?
Diabetes insipidus is caused by?
antidiuretic hormone (ADH) HYPOsecretion.
Diabetes mellitus is characterized by the following except?
Lymphoid hemopoiesis occurs mainly in the bone marrow.
The most important components of the cytoplasm of RBCs are hemoglobin and carbonic anhydrase.
Rh incompatibility between a sensitized Rh+ woman and an Rh- fetus can cause hemolytic disease of the newborn.
Monocytes differentiate into large phagocytic cells.
After a wound is sealed, tissue repair is followed by fibrinolysis.
Hematocrit is ____________ of the total blood volume.
_____________ is the most abundant protein in plasma.
Tissues can become edematous (swollen) when?
there is dietery protein sufficency
Erythrocytes transport oxygen and serve to?
transport carbon dioxide
An increased erythropoietin (EPO) output by the kidneys would lead to all of the following except?
______________ is more likely to cause anemia than any of the other factors below.
Correction of hypoxemia is regulated by?
a NEGATIVE feedback loop
The ABO blood group is determined by _____________ in the plasma membrane of RBCs.
RhoGAM is an antibody given to Rh- women who give birth to a Rh+ child. RhoGAM is what type of plasma protein?
gamma (y) globulin
The main reason why an individual AB, Rh-negative cannot donate blood to an individual A, Rh-positive is because?
anti-B antibodies in the RECIPIENT will agglutinate RBCs of the donor.
These are the most abundant agranulocytes.
Leukopoiesis begins with the differentiation of?
Pluripotent stem cells (PPSCs)
All these can cause leukopenia except?
The cessation of bleeding is specifically called?
All of these prevent the spontaneous formation of a clot except?
presence of tissue thromboplastin
Most strokes and heart attacks are caused by the abnormal clotting of blood in an unbroken vessel. Moreover, a piece of the ____________ (clot) may break loose and begin to travel in the bloodstream as a(n) ______________.
The vagina has no glands but it is moistened by mucus from glands in the cervical canal.
The number of ovarian follicles declines with age, leading to a reduction of estrogen levels.
The proliferative phase of the uterus is drive by estrogen from the ovaries?
Human chronic gonadotropin (HCG) stimulates the corpus luteum to grow and secrete estrogen and progesterone.
Oxytocin stimulates contraction of myoepithelial cell of the mammary acini.
The ___ arteries rhythmically consrict and dialate causing the uterine mucose to blanch and flush with blood.
Most of the natural lubrication during female sexual excitment is proveded by the?
greater vestivular (Bartholin) glands
_____ are found in both male and femal external genitalia, but the ____ is/are only found in the female.
Corpora cavernosea; vestibular bulbs
Follicles are located in the?
cortex of the ovary.
_____ acts primarily in the uterus.
During climcteric, sudden ______ may cause hot flashes.
vasodilation of cutaneous arteries
The ovulated egg is at?
After expelling the oocyte, the follicle becomes the ____ and secreates_____.
corpus luteum; ESETROGEN AND PROGESTERONE
during embryonic development.
Which of these blood hormone levels reaches its maximum during the luteal phase?
The ____ phase is the one associasted with menstrul cramps and typically occurs _____ of the cycle.
premenstrual; days 27 to 28
During the plateau phase, the flans and clitoris swell as the _____ arteries dilate and the corpus and corpora _____ engorge with blood.
The basis of pregnancy test kits is the presence of ___, which is secreated by the _____.
human chorionic gonadotropin (HCG); blastocyst and placenta
The most abundant estrogen of pregnancy is ___, but one that accounts for the most of the estrogenic effects in pregnancy is ____.
Milk ejection, stimulation of nerve endings in the ____ leads to the release of _____ from the pituitary.
nipple and areola; oxytocin
The fertilization membrane is the endometrial tissue that receives the conceptus.
The embryonic stage extends from 16 days through the end of week 8.
Trophoblastic nutrition refers to the nutrition of the conceptus before it implants.
Premature infants suffer especially from multiple dysfunctions resulting from inadequate liver function.
Life expectancy has steadily incread in teh last century, whereas life span has not.
In the slow block to polyspermy, sperm penetration releases an inflow of _____, which in turn stimulates the ______.
CA2+; cortical reaction
The optimal "window of opportunity" to conveive a child is?
a few days before ovulation to less than a day after
In the blastocyst, the trophoblast will become_____, wheras the embryoblast will become______.
part of the placenta; the embryo
During implantation, the trophoblast divides into a deep layer, the ____, composed of individual cells, and a superficial layer, the _____, composed of multinucleate mass of cytoplasm.
Prior to ejaculation, ____ in the sperm membrane prevents premature release of ____.
cholesterol; acrosomal enzymes
By the end of 8 weeks, the individual is considered a fetus because...
all of the organ systems are present.
In fetal circulation, the ____ bypassses the liver and the _____ bypasses the lungs.
ductus VENOSUS, ductus arteriosus
Oxygenated blood reaches the fetus through the?
The digital rays of a fetus give rise to?
fingers and toes
During birth, an infant is normally stimulated to breath by?
CO2 accumulating in the babys blood.
Which of these organ systems faces the greatest physiological challenge in the transitional period after birth?
Down syndrome (trisomy-21) results from
Urine retention is greater problem for elderly men than for elederly women because men
usually develop benign prostatic hyperplasia
are DNA segments at each end of a chromosome.
Which of the following systems shows the least overall senescene?
Mucous membranes prevent most pathogens from entering the body because of the stickiness of the mucus and the presence of lysozymes.
Pyrogens act by increasing the set point for body tempature in teh thalamus.
Helper T cells respond only to epitopes attached to MHC proteins.
Naive T cells can synthesize antibodies.
Some antibodies against foreign antigens can react to similar self-antigens causing an autoimmune disease.
Special lymphatic vessels called lacteals absorb dietary ___ that are not absorbed by the blood capillaries.
_____ are the largest of the lymphatic vessels and they empty into the ____.
Collecting ducts; subclavian veins
This is the only lymphatic organ with afferent lymphatic vessels.
____ are found especially in the myucous membrane, standing guard against parasites, and allergens.
____ are secreted by cells infect with viruses, alerting neighboring cells and protection them from becoming infected.
This is the first of a series of neutrophil behaviorsin inflammation?
All these cellular agents participate in inflammation except?
cytotoxic T cells
___ are antimicrobial proteins.
Cellular (cell-meditated) immunity is efefctive against?
T cells undergo positive selection in the thymus which means?
they multiply and form clones of identical T cells
All of the following can act as antigen-presenting cells except?
Helpter T (TH) cells do not?
secrete fever producing chemicals
Memory T cells can live up to?
Each immunoglobulin (Ig) has___ antigen-bonding site(s).
Before B cells secrete antibodies they differentiate into?
Beta cell destruction that causes type 1 diabetes mellitus is a(n)
type IV (delayed) hypersensitivity
The nose is divided into right and left halves termed the?
The most numerous cells in the lungs are called
What is the basic distinction between an aveolar duct and alveolar atrium?
____ states that the total pressure of a gas mixture is equal to the sum of the partial pressure of its individual gases.