Courses for Kids
Free study material
Offline Centres
Store Icon

Metamerically segmented body exhibits
A. Repeated segments
B. Linear repetition of body parts
C. Repetition of nephridia
D. Repetition of reproductive organs

Last updated date: 25th Jun 2024
Total views: 387.6k
Views today: 5.87k
387.6k+ views
Hint: There are fundamental features common to various individuals in relation to the arrangement of cells, body symmetry, nature of coelom, patterns of the digestive system, circulatory system, and respiratory system.

Complete answer: METAMERISM: Metamerism or segmentation refers to a linear repetition in parts of the animal body. It occurs in three highly organized phyla: Annelida, Arthropoda, and Chordata.
Each segment is called metamere or somite. Segmentation often affects both external and internal structures. Such a condition is called metameric segmentation In chordates, the segmentation is apparent only in the embryonic stage. In adult chordates, segmentation is visible in the internal structures, such as vertebrae, ribs, nerves, and blood vessels. Other animals have an unsegmented body.
So the correct answer is option B-Linear repetition of body parts
Additional information:
COELOM: The presence or absence of a cavity between the body wall and the gut wall, the body cavity lined by mesoderm is known as a coelom.
-Acoelomates: Animals that do not possess cavities or coelom in the digestive tract. Eg. Platyhelminthes
-Coelomates: Animals possessing coelom between the body wall and the digestive tract are called coelomates. e.g., annelids, Arthropoda, etc.
-Pseudocoelomates: In some animals, the body cavity is not lined by mesoderm instead the mesoderm is present in the cavity in between the ectoderm and endoderm. Eg. Aschelminthes
NOTOCHORD: The notochord is a solid, unjointed, stiff but flexible rod located in the mid-dorsal line between the alimentary canal and the nerves cord of the embryo. Notochord provides support and points for muscle attachment. It persists throughout life in the lower chordates but in the higher ones, it is surrounded or replaced partly or fully in the adult by a jointed vertebral column or backbone.
There is no notochord in non-chordates.

Note: Tapeworm’s body consists of a row of units called proglottids. The latter are budded off from the neck as the worm grows, and are not of embryonic origin. Such segmentation is called pseudometamerism or false segmentation.