Define and explain the three features of the animal body plan and the major groups that these features distinguish.

Answer 1

The three features of the animal body plan are symmetry, body cavity, and segmentation.

1. Symmetry: Symmetry refers to the organization of body parts around a central axis. Animals can either have radial symmetry, where body parts are arranged around a central point and can be divided into identical halves by multiple planes, or bilateral symmetry, where the body is divided into two mirror-image halves by a single plane. Radial symmetry is seen in animals like jellyfish and sea anemones, while bilateral symmetry is seen in animals like humans and dogs.

2. Body cavity: The body cavity is the space between the body wall and the internal organs. Animals can either have a coelom, a fluid-filled body cavity completely lined by mesoderm, or no coelom, where the body cavity is absent or partially filled with tissue. Animals with a coelom are called coelomates, and include groups like mollusks, arthropods, and chordates. Animals with no coelom are called acoelomates, and include groups like flatworms.

3. Segmentation: Segmentation refers to the division of the body into repeated segments. Segmentation is seen in animals like annelid worms and arthropods, where the body is divided into repeated segments with similar structures. Segmentation allows for greater flexibility and specialization in body parts.

In summary, these three features of the animal body plan distinguish major groups of animals and help us understand their structure, function, and evolution.

Answer 2

For two vertical angles where ∠1=2x+26°
and ∠3=3x−32°
, what is the measure of each angle?
°
Correct answers:
142

Answer 3

To find the measure of each angle, we need to set ∠1 and ∠3 equal to each other and solve for x:

∠1 = ∠3
2x + 26° = 3x - 32°
58° = x

Now that we know the value of x, we can substitute it into either equation to find the measure of the angles:

∠1 = 2x + 26°
∠1 = 2(58°) + 26°
∠1 = 142°

∠3 = 3x - 32°
∠3 = 3(58°) - 32°
∠3 = 142°

Therefore, each angle measures 142°.