Most bilaterally symmetric animals have a definite head end a condition called?

Cephalization is an evolutionary trend in which, over many generations, the mouth, sense organs, and nerve ganglia become concentrated at the front end of an animal, producing a head region. This is associated with movement and bilateral symmetry, such that the animal has a definite head end.

1. What are bilaterally symmetrical animals?
2. What animal group has bilateral symmetry?
3. Why is having a head associated with being bilaterally symmetric?
4. What do animals with bilateral symmetry have in common?
5. Which of the following is bilaterally symmetrical?
6. What is symmetry and bilateral symmetry?
7. Do reptiles have bilateral symmetry?
8. Do fishes have bilateral symmetry?
9. Which of the following animals displays radial symmetry?
10. How does an animal with bilateral symmetry differ from an animal with radial symmetry?
11. What animals have no bilateral symmetry?
12. Are bilaterally symmetric animals usually sessile?
13. Which of the following animals are true Coelomates with bilateral symmetry?
14. Which of the following phyla include groups of animals which are bilaterally symmetrical and triploblastic?
15. Which of the following groups of animals is bilaterally symmetrical and triploblastic sponges Coelenterates cnidarians Aschelminthes round worms Ctenophores?
16. What does bilateral symmetry mean in biology?

What are bilaterally symmetrical animals?

Bilateral symmetry involves the division of the animal through a sagittal plane, resulting in two mirror-image, right and left halves, such as those of a butterfly, crab, or human body. Animals with bilateral symmetry have a “head” and “tail” (anterior vs. posterior), front and back (dorsal vs.

What animal group has bilateral symmetry?

The vast majority of animals display bilateral symmetry; also known as plane symmetry, this is a trait that applies to 99% of all animals, in the majority of phyla: Chordata, Annelida, Arthropoda, Platyzoa, Nematoda, and most Mollusca.

Why is having a head associated with being bilaterally symmetric?

The advantages of bilateral symmetry include the formation of a head and tail region, where the head region can house a detailed nervous system, and more directional movement to include the ability to move straight forward.

What do animals with bilateral symmetry have in common?

Animals with bilateral symmetry have a “head” and “tail” (anterior vs. posterior), front and back (dorsal vs. ventral), and right and left sides. All true animals, except those with radial symmetry, are bilaterally symmetrical.

Which of the following is bilaterally symmetrical?

Detailed Solution. The correct option is Earthworm. The earthworm is a bilaterally symmetrical organism. It belongs to the phylum Annelida.

What is symmetry and bilateral symmetry?

An organism that is symmetrical (showing symmetry) would have a balanced distribution of duplicate parts on each side of the axis. ... When an organism shows bilateral symmetry, the body plan is divisible into equal mirror halves in a sagittal plane.

Do reptiles have bilateral symmetry?

Bilateral symmetry is characteristic of the vast majority of animals, including insects, fishes, amphibians, reptiles, birds, mammals, and most crustaceans.

Do fishes have bilateral symmetry?

Mostly all marine organisms, including all vertebrates and some invertebrates are bilaterally symmetrical. This includes marine mammals such as dolphins and whales, fish, lobsters, and sea turtles.

Which of the following animals displays radial symmetry?

Because of the circular arrangement of their parts, radially symmetrical animals do not have distinct front or back ends. They may have distinct top and bottom sides. Some examples of these animals are jellyfish, sea urchins, corals, and sea anemones. A bicycle wheel also has radial symmetry.

How does an animal with bilateral symmetry differ from an animal with radial symmetry?

Explanation: The bilateral symmetry animals body are divided into two equal halves from a particular radius passing through the centre. The direction of cutting is fixed. ... The radial symmetry animals body are cut into two equal halves from all the radii of the animals body passing through the centre.

What animals have no bilateral symmetry?

They start off symmetrical, but as adults they get that wandering (literally) eye that shifts to one side of their face, so that they can hide flat in the sand and see their prey above. Narwhals. Their unicorn horn is actually one of their incisor teeth that grew straight through their face. So it's off to the side.

Are bilaterally symmetric animals usually sessile?

bilaterally symmetric animals are usually sessile and, therefore, unable to move freely. You just studied 45 terms!

Which of the following animals are true Coelomates with bilateral symmetry?

Annelids found in marine , freshwater and brackish water. They are the true coelomates with bilateral symmetry.

Which of the following phyla include groups of animals which are bilaterally symmetrical and triploblastic?

Animals of phylum platyhelminthes are triploblastic and bilaterally symmetrical.

Which of the following groups of animals is bilaterally symmetrical and triploblastic sponges Coelenterates cnidarians Aschelminthes round worms Ctenophores?

Aschelminthes are bilateral symmetrical and triploblastic animals, e.g. Ascaris. Coelenterates are radially symmetrical and diploblastic animals, e.g. Obelia.

What does bilateral symmetry mean in biology?

Definition of bilateral symmetry

: symmetry in which similar anatomical parts are arranged on opposite sides of a median axis so that only one plane can divide the individual into essentially identical halves.