Search results
Results From The WOW.Com Content Network
The locking is completed by circular muscles just inside the female's vagina; this is called "the knot" tightening thus preventing the male from withdrawing. The circular muscles also contract intermittently, which has the effect of stimulating ejaculation of sperm, followed by prostatic fluid, as well as maintaining the swelling of the penis ...
An open circulatory system is made up of a heart, vessels, and hemolymph. This diagram shows how the hemolymph is circulated throughout the body of a grasshopper. The hemolymph is first pumped through the heart, into the aorta, dispersed into the head and throughout the hemocoel, then back through the ostia that are located in the heart, where ...
The hemipenis is the intromittent organ of Squamata, [4] which is the second largest order of vertebrates with over 9,000 species distributed around the world. They differ from the intromittent organs of most other amniotes such as mammals, archosaurs and turtles that have a single genital tubercle, as squamates have the paired genitalia remaining separate. [5]
Get a daily dose of cute photos of animals like cats, dogs, and more along with animal related news stories for your daily life from AOL.
The reason why some researchers are skeptical about animals having a sense of humor is that it serves no evolutionary purpose. For humans, it's a bonding strategy. For humans, it's a bonding strategy.
Baculum of a domestic dog; The arrow points to the bottom groove where the urethra is located. The tip is to the right. Inside the corpus spongiosum lies the baculum.This allows the male dog to enter into the vagina before the erectile tissue is swollen.
While humans, as well as other vertebrates, have a closed blood circulatory system (meaning that the blood never leaves the network of arteries, veins and capillaries), some invertebrate groups have an open circulatory system containing a heart but limited blood vessels. The most primitive, diploblastic animal phyla lack circulatory systems.
The exact reason for this behavior is unknown, but some studies show that it relates to stress. Females have nonrespiratory air sacs containing anoxic air, and the waving pushes this air into her lungs. The resulting stress causes her cloaca to open, and aids the male in inserting his hemipenis. The stronger and more frequent the caudocephalic ...