Question

Tube -within -tube body plan is shown by
A. Coelenterates
B. Flatworms
C. Annelida
D. Sponges

Answer 1

Most animals have a body plan best described as a tube-within-a-tube. This type of body plan has two openings: one for food to enter the body (mouth) and one for wastes to leave the body (anus). This tube-within-a-tube plan has specialization of parts along the tube, such as a stomach, intestine, etc.

Complete answer:
Cylinder - inside - tube body plan is appeared by phylum Annelida. These are the qualities of Annelida: Free-living, earthly or sea-going structure (freshwater or marine). The body is long, round and hollow, and metameric ally sectioned. The body divider comprises the fingernail skin, epidermis, and musculature.

Body depression is a genuine coelom, lined by epithelium. The stomach related framework is finished. Breath is either through the skin or through gills. Discharge with the assistance of trademark nephritis. The presence of a circulatory framework (shut sort). Hemoglobin broke down straightforwardly in the plasma.

The sensory system comprises a nerve ring and a twofold ventral nerve rope with segmental ganglia. Headway with the assistance of setae or paranoia. Multiplication by sexual strategies. Either unisexual or promiscuous improvement might be immediate or roundabout. The body has a genuine coelom.

Hence correct answer is option (C)

Note: Some creatures process blind sac body plan which have only one opening in the body.The tube-like digestive system starts with a single opening by mouth which the food is taken inside and the digested food is expelled through the same opening.