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.
Finally he added the results he came up with that supported his hypothesis, that turbidity decreases egg care but increases egg survival. From both the abstract and the title, the reader can easily assume that Jarevenpaa is trying to find evidence to support his hypothesis that algal bloom has an effect on father’s care to his egg by knowing the amount of survived eggs. The introduction of the paper, “Algal blooms decrease care but increase egg survival in a fish with paternal care”, was rich enough to give the reader an idea about the background and the importance of this experiment conducted on sand goby fish. For every idea he included he cited more than one paper to support his ideas. Jarvenpaa started by explaining how changes in the environment would affect the parental care and he gave fish as an example.
They range in size from a few millimeters up to a bell size of two meters across, with tentacles up to thirty-six meters long. Typically less than five percent of a jellyfish’s body is "solid organic material" (Halstead, Poisonous 96-97). Jellyfish have reproductive cycles that involve a sessile polyp and a free-living medusa state. The polyp is asexual, while the medusa is sexual (Williamson et al. 121).
Rhincondon typus is known to be primarily a loner traveling by itself the majority of the time, although they are known to seasonally aggregate in specific areas. Life cycle Due to the large expanse and sheer size of the whale shark much of the species lifecycle is unknown. Although in recent years some aquariums have created exhibits large enough to contain the whale shark enabling more thorough research. It is largely speculated that the ratio of male to female whale sharks dictate the structure of their mating system (Martin 2007). Rhincodon typus are oviparous giving birth to live young and have been documented to carry up to 300 embryos at one time.
Human Reproduction and Development Human reproduction employs internal fertilization, and depends on the integrated action of hormones, the nervous system, and the reproductive system. Gonads are sex organs that produce gametes. Male gonads are the testes, which produce sperm and male sex hormones. Female gonads are the ovaries, which produce eggs and female sex hormones. The Male Reproductive System Testes are suspended outside the abdominal cavity by the scrotum, a pouch of skin that keeps the testes close or far from the body at an optimal temperature for sperm development.
The follicles develop, usually one at a time, in response to the various sex hormones until they become primary follicles. Describe the fallopian tube and its purpose. The fallopian tubes connect the ovaries to the uterus. Each fallopian tube resembles a long, thin funnel that is wider at the ovary and narrower at the uterus. At the ovary end, the fallopian tube has finger like projections called fimbriae, these encourage the mature sperm to enter the fallopian tube.
Turtles have very unique eyes as they feature eyelids. The eyes are also where the saltwater they take in during eating is excreted which is why some will argue that sea turtles cry. The dorsal (top) side of the shell is called the carapace.Depending on species, the adult carapace ranges in shape from oval to heart-shaped. They have a very good sense of smell and use it to find prey. It is believed that the young also use it to find their way to the water for the first
There were also a lot more different types of amphibians in the past, but now we have only 3 orders of living amphibians (salamanders, frogs and toads, and the worm-like caecilians), collectively known as lissamphibians. Reptiles did not evolve from a Lissamphibian. They, like the lissamphibians, evolved from one of the extinct amphibians. Therefore it would be incorrect to say that reptiles evolved from a frog, salamander or caecilian. Once the reptiles evolved, they began diversifying.
Most of the fossils that have been found are extremely small, only about 1-5 mm. The oldest known cephalopods, which include squids, octopi, and cuttlefish, date back to much later times, in the Late Cambrian era, which ended around 488 million years ago. The fossil record gives very little evidence to prove how mollusks came about and evolved into what they are today. Because of the little evolutionary evidence, scientists have turned to comparative molecular biology. Biologists have inferred from studies that Phylum Mollusca and Phylum Annelida, which consists of segmented worms, share a common ancestor.