When oxygen is absent, anaerobic respiration occurs ('an' means without).
Answer:
a. Excretion is accomplished by paired protonephridia with flame cells in every segment of the body. True
Most anelids have structures called metanephrids or protonephridia. Both structures are homologous to the kidneys and have the function of excresion, A pair are present in every segment of the body.
b. If the organs in one segment fail, the organs of another segment will still function. False
It is false because all segments are interrelated and have different functions depending on their location.For example, the first segment is where the sensory appendages are, such as the antennae and the eyes. The second segment is where the mouth is. There are a series of parapod segments to move, collectively called metameres and ends in a terminal portion called pigidium, where the anus is located.
c. Annelids possess both circular and longitudinal muscles that produce waves of contraction that are propagated down through the points eBookseries of segments.True
True because anelids have circular and longitudinal muscles that serve to function the hydrostatic skeleton.
d. Segmentation has allowed for specialization in the anterior of the annelid body, which has provided for a more sophisticated nervous system. True
True because the segmentation allows to have a nervous system formed by a ventral nerve cord provided with ganglia and lateral nerves in each segment.
The seahorse is found in many different locations around North and South America. They are typically located in the shallow tropical waters that are quite warm. They will be found living along the coral, the sea grass, and the mangroves. In Europe they are known to reside in the Thames estuary. Many of the larger species are living in the Mediterranean Sea.
Many species of seahorses are very territorial. The males often have about 11 square feet of territory. The females have up to 1,100 square feet. What they live though will influence how much area they have. In many regions that habitat range has gotten smaller and smaller.
In captivity the seahorses will be limited to a large aquarium. This can be a huge change in home range habitat for them. That is why the stress levels are very high and the survival rate low. Young in a captive state are more likely to do well because they haven’t become accustomed to the wide territory.
As a result the seahorses living in a given area have become more aggressive. They have also suffered from higher stress levels and more forms of disease. The aggressive behavior is typically when males are looking for females that they can mate with. It is also common when they are fighting for territory or food and that extends to both genders.
