1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Vera_Pavlovna [14]
3 years ago
15

For many years, scientists believed that almost all animal lineages burst into being during the Cambrian era (just after the end

of the Precambrian super eon). However, there have been many recent findings of animal-like fossils and "trace fossils" (fossils of an animal-like organism's movement) from the late Precambrian. Which of the following best explains why it took so long to realize there was animal-like life in the Precambrian?
A) Animals from the late Precambrian had soft bodies.
B) There were many hard-shelled animals in the Cambrian.
C) The global climate was such that there was poor fossilization in the Precambrian.
D) There were very few animals during this period.
Biology
1 answer:
frosja888 [35]3 years ago
6 0

Answer:

Option (A)

Explanation:

The Precambrian represents the time period, right from the beginning of the earth to about 540 million years back. It is divided into 3 parts, namely the Hadean, the Archean and the Proterozoic. Throughout this geological time, vast changes have taken place on earth. The first life forms of about 3.8 billion years old, that existed on earth were the simple unicellular organisms, whose traces were only found at some particular places. These organisms were very small and are comprised of soft bodies, so they were affected by the earth's dynamic processes. The organisms in order to get fossilized must contain hard parts. Due to the presence of soft bodies, the organisms were not fossilized and so it took a long time to demarcate that the late Precambrian organisms were animal-like life.

hence, the correct answer is option (A).

You might be interested in
Which linkages would you expect to find at a branch point in glycogen or amylopectin?
shusha [124]

Answer:

α-1,6-glycosidic linkage.

Explanation:

The carbohydrates are the polymers made of the sugars and bonded together through the glycosisdic bonds. The monosaccharides are the simplest unit of the carbohydrates.

The glycogen and amylopectin share similar structural features. Both have α-1,4-glycosidic linkage in their linear structure. The branching has been introduced in the glycogen and amylopectin structure through the α-1,6-glycosidic linkage.

Thus, the answer is α-1,6-glycosidic linkage.

6 0
3 years ago
What is the main function of lipids
Marta_Voda [28]

Answer:

They provide energy, protection and insulation for the organs in the body. They're also very important in the cell membranes.

Explanation:

3 0
3 years ago
Read 2 more answers
the following shows a graph of the energy changes taking place as a chemical reaction progress. If an enzyme is added, which arr
Alekssandra [29.7K]
The arrow representing the activation energy will decrease in magnitude.

This arrow will be beginning at the x-axis and going up to the maximum of the graph. The reason that its magnitude decreases is because enzymes provide  alternate pathways to reactions; the new pathway has a lower activation energy, so the reaction occurs faster when an enzyme is added. This is why enzymes are referred to as biological catalysts and are a vital part of an organism's body
8 0
3 years ago
Read 2 more answers
During the _______ phase, the muscle is returning to resting length.
tangare [24]

Answer:

The correct answer is: Eccentric phase.

When talking about movement, we are talking about the activation of muscle fibers in order for this process to happen. In order for this to happen, motor neurons must activate the phases of muscle excitation, contraction and relaxation, so that the sarcomeres, and thus the fibers, can generate movement.

In essence, there are three stages, or phases, to complete muscle movement:   the concentric phase, which is when the muscle fibers are excited and begin the process of contraction. This means the muscle fibers will contract and generate movement, generating a shortening. Then we have the isometric stage, a moment in which there is no longer any more shortening of the muscle fibers, so basically, the movement is held and there is no further contraction, but neither is there relaxation of the muscle fibers. Finally, we have the eccentric phase. This phase is characterized precisely because it is the moment when the muscles begin to return to their resting position.

3 0
3 years ago
I neeeeed helppp plz
EleoNora [17]

Answer:

amino acids

Explanation:

3 0
3 years ago
Read 2 more answers
Other questions:
  • Most heritable differences are due to
    10·2 answers
  • When seeds germinate, roots grow downward and stems grow upward in response to gravity. This response to gravity is called _____
    5·1 answer
  • Which hormone is largely responsible for women having wider hips than men?
    10·2 answers
  • Enzymes are proteins that speed up reactions by
    7·2 answers
  • A relatively rapid form of mass movement that is most common in dry mountainous regions is _____.
    8·2 answers
  • The sex of the child is determined by the male parent. Justify your statement.
    10·1 answer
  • Casual contact in general is not a risk factor for infection of HIV true or false
    7·2 answers
  • What type of cell is produced by ghenprocess meiosis
    10·1 answer
  • If the number of hydrogen ions being pumped into the thylakoid is rapidly decreasing, what is most likely happening?
    6·1 answer
  • The Chemical composition of the cell membrane
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!