Lancelet is a chordate but not a vertebrate because it lacks a backbone
Explanation:
The subphyla of the phylum Chordata are - Vertebrata, Urochordata and cephalochordate
Those chordates with a structural backbone belong to Vertebrata.
Urochordates and cephalochordates lack a backbone and hence are termed invertebrate chordates.
Lancelet is an invertebrate chordate of the subphylum – Cephalochordata.
The lancelets consist of a notochord that extends right from the head till the tail at the dorsal surface. The notochord acts like the backbone and provides support and a semi-flexible structure to aid in the movement of the organism.
They lack a developed nervous system like vertebrates but only has a dorsal nerve tube
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Answer:
1. Leads to mixing of genetic materials hence variation within species
2. Leads to offspring with hybrid viguor that tend to show high and adaptability to environmental conditions.
3. Variations due to sexual reproduction leads to improvement of species hence evolutionary changes that may bring about specialisation
Circulatory system and nucleus
Skeletal and Muscular Systems
<span>Adaptation is a change or the process of change by which an organism or species becomes better suited to its environment.
Knowing the definition of each of the terms is the easiest way to get the answer. </span>
