It is also interesting to note that the act of intercourse itself ends not with the female orgasm, but with the male. Due to the biological make-up of males and females, the actual act of sex (penetration) is constructed around the male orgasm. When exploring the role of the orgasm, we have to take into consideration complexity of the female orgasm. Society makes up certain stereotypes for males and females in terms of sexual relationships. Here we take into consideration the malefemale binary in terms of sex and emotion.
Jellyfish do not have a back or front, left or right. They don’t have a heart, head, legs, or fins (Zimmer). They have a stomach pouch to hold food, the bell (body), oral arms which bring the captured food to the mouth, tentacles which sting and kill prey, a mouth connected to digestive structures to digest food, and gonads which are reproductive organs. Jellyfish are also 95% water (Northeaster University). Jellyfish move by expanding and contracting to push the water behind them.
These physical changes have resulted in different phyla, ranging from basic structures, like sponges to advance systems, like that of an octopus. Porifera is the most simplistic phylum under the kingdom Animalia. The sponges have no tissue layers, but instead an interior and exterior layer with a gelatinous middle layer that separates the two. They are the only phylum with asymmetrical symmetry. Throughout the advancing phyla it will be shown this trait is lost.
Their bodies are wide and flat with a sturdy carapace and a segmented abdomen. They have a pair of eyes at the front of the carapace and three eyes further back on the carapace on each side. Even though Tailless Whip Scorpion possesses eight eyes their eyesight is poor to below average. Their pedipalps serve as sensors and are modified for grabbing and keeping possession of their prey. Their first pair of legs are used as sensory organs and not used for walking.
Because echinoderms are so skilled at this process they were one of the favorite models for pioneer regenerationists of the 19th and early 20th centuries. The capability for starfish to regenerate depends on the individual; as well as how capable they are for histogenetic and morphogenetic plasticity expressions. The ability to do this self-repair not only is an advantage for the individual but it also hel... ... middle of paper ... ...n in Starfish Caught by Towed Demersal Fishing Gears." Marine Biology 138.3 (2001): 527-36. Print.
Unlike other worms these freshwater flatworms are unsegmented. They are acoelomates, meaning that they lack a coelom or a complete gut cavity. Their demonstration of bilateral symmetry has been linked directly to cephaliza... ... middle of paper ... ...neration in Planaria." Encyclopedia of Life Sciences (2001): n. pag. National Center for Biotechnology Information.
NOTES Characteristics Flatworms are parasitic unsegmented, bilaterally symmetrical worms that lack a coelom but that do have three germ layers. Some forms are free living but many are parasitic. Flatworms have a cephalized nervous system that consists of head ganglion(brain), usually attached to longitudinal nerve cords that are interconnected across the body by transverse branches. Flatworms lack a respiratory or circulatory system, these functions take place by absorption through the body wall. Nonparasitic forms have a simple, incomplete gut, even this is lacking in many parasitic species.
. It does not contain peroxisomes or mitochondria but does have a mitosome. A specialized feature of Giardia lamblia, known as an adhesive disc, ensures the attachment of the parasite to the intestinal mucosa in the infected host. Giardia lamblia employs different strategies for survival by existing in two different forms throughout its life cycle. Outside of the host, Giardia lamblia is an infectious but dormant cyst, which protects the parasite.
However, most erections are a combination of these two pathways (Steer, 2000), so a later consideration of this second pathway may become prudent. Central nervous system The normal psychogenic pathwa... ... middle of paper ... ...eletal muscles, including the larynx and pharynx. The sacral PNS areas are most related to sexual arousal and activity. The sacral plexus, comprising sacral nerves S2-S4, innervates the genitals (Lue et al., 1983), with the preganglionic neurons running from the pelvic nerves to the pelvic plexus where they meet sympathetic neurons and merge to form the cavernous nerves (Steer, 2000). These cavernous nerves exit the pelvic plexus via the pelvic fascia, fuse with the prostatic capsule, and enter the penis through a variety of routes including through the levator ani and urethra, through entering the corpus spongiousum, or to the penile crura The PNS additionally receives information from the somatic pudendal nerve, which receives sensory information from and additionally innervates the penis, as well as possibly from hypogastric nerve afferents (Rosen & Sachs, 2000).
The giant pacific octopus is in the kingdom Animalia because it is multicellular, eukaryotic, and has no cell walls. In addition to this, the giant pacific octopus reproduces sexually and has cells that are used for specific functions. (Kalupa, 2012) The octopus is in the phylum Molluska. It is under Molluska because the octopus has a soft body (mollus meaning soft), and is a cephalopod. It also has bilateral symmetry.