The statement that the “Cambrian explosion actually consists of three explosions, not one.” Concept introduction : Cambrian explosion refers to the rapid diversification of animals that occurred 535-525 million years ago, during the Paleozoic era. Simple, soft bodied animals also called Ediacaran fauna inhabited the earth before the Cambrian explosion. There are various hypotheses that explain the Cambrian explosion. According to one hypothesis, the appearance of a prey-predator relationship led to the Cambrian explosion. The predators in the Cambrian period acquired novel adaptations for predation. This led to natural selection of prey with hard bodies. The hard bodies helped them in defense from predators. Another hypothesis emphasizes on the increase in atmospheric oxygen. The increase in atmospheric oxygen led to the evolution of animals with high metabolic rate and larger body size. According to another hypothesis, the evolution of Hox genes (developmental genes) and microRNAs led to the evolution of animals with complex bodies. The evidences of first arthropods and chordates come from the rock strata of the Cambrian period.

Question

Want to see the full answer?

Answer 1

Question

Definition Definition Organ system that helps in the digestion of food by mechanical and biochemical processes. The digestive system breaks down food into simpler components that enable the body to then absorb or transport nutrients. The human digestive system includes the gastrointestinal tract or alimentary canal and the associate glands. The organs of the gastrointestinal tract include the mouth, pharynx, esophagus, stomach, small intestine, and large intestine. The associated glands include salivary glands, liver, gallbladder, and pancreas.

Chapter 32.4, Problem 3CC

Summary Introduction

To evaluate: The statement that the “Cambrian explosion actually consists of three explosions, not one.”

Concept introduction:

Cambrian explosion refers to the rapid diversification of animals that occurred 535-525 million years ago, during the Paleozoic era. Simple, soft bodied animals also called Ediacaran fauna inhabited the earth before the Cambrian explosion. There are various hypotheses that explain the Cambrian explosion.

According to one hypothesis, the appearance of a prey-predator relationship led to the Cambrian explosion. The predators in the Cambrian period acquired novel adaptations for predation. This led to natural selection of prey with hard bodies. The hard bodies helped them in defense from predators.

Another hypothesis emphasizes on the increase in atmospheric oxygen. The increase in atmospheric oxygen led to the evolution of animals with high metabolic rate and larger body size.

According to another hypothesis, the **evolution of Hox genes (developmental genes) and microRNAs** led to the evolution of animals with complex bodies. The evidences of first arthropods and chordates come from the rock strata of the Cambrian period.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Students have asked these similar questions

Skip to main content close Homework Help is Here – Start Your Trial Now! arrow_forward search SEARCH ASK Human Anatomy & Physiology (11th Edition)BUY Human Anatomy & Physiology (11th Edition) 11th Edition ISBN: 9780134580999 Author: Elaine N. Marieb, Katja N. Hoehn Publisher: PEARSON 1 The Human Body: An Orientation expand_moreChapter 1 : The Human Body: An Orientation Chapter Questions expand_moreSection: Chapter Questions Problem 1RQ: The correct sequence of levels forming the structural hierarchy is A. (a) organ, organ system,... format_list_bulletedProblem 1RQ: The correct sequence of levels forming the structural hierarchy is A. (a) organ, organ system,... See similar textbooks Bartleby Related Questions Icon Related questions Bartleby Expand Icon bartleby Concept explainers bartleby Question Draw a replication bubble with two replication forks.blue lines are DNA single strands and red lines are RNA single strands.indicate all 3' and 5’ ends on all DNA single…

Provide an answer

Question 4 1 pts Which of the following would be most helpful for demonstrating alternative splicing for a new organism? ○ its proteome and its transcriptome only its transcriptome only its genome its proteome and its genome

Answer 2

Question

Definition Definition Organ system that helps in the digestion of food by mechanical and biochemical processes. The digestive system breaks down food into simpler components that enable the body to then absorb or transport nutrients. The human digestive system includes the gastrointestinal tract or alimentary canal and the associate glands. The organs of the gastrointestinal tract include the mouth, pharynx, esophagus, stomach, small intestine, and large intestine. The associated glands include salivary glands, liver, gallbladder, and pancreas.

Chapter 32.4, Problem 3CC

Summary Introduction

To evaluate: The statement that the “Cambrian explosion actually consists of three explosions, not one.”

Concept introduction:

Cambrian explosion refers to the rapid diversification of animals that occurred 535-525 million years ago, during the Paleozoic era. Simple, soft bodied animals also called Ediacaran fauna inhabited the earth before the Cambrian explosion. There are various hypotheses that explain the Cambrian explosion.

According to one hypothesis, the appearance of a prey-predator relationship led to the Cambrian explosion. The predators in the Cambrian period acquired novel adaptations for predation. This led to natural selection of prey with hard bodies. The hard bodies helped them in defense from predators.

Another hypothesis emphasizes on the increase in atmospheric oxygen. The increase in atmospheric oxygen led to the evolution of animals with high metabolic rate and larger body size.

According to another hypothesis, the **evolution of Hox genes (developmental genes) and microRNAs** led to the evolution of animals with complex bodies. The evidences of first arthropods and chordates come from the rock strata of the Cambrian period.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Answer 3

Question

Definition Definition Organ system that helps in the digestion of food by mechanical and biochemical processes. The digestive system breaks down food into simpler components that enable the body to then absorb or transport nutrients. The human digestive system includes the gastrointestinal tract or alimentary canal and the associate glands. The organs of the gastrointestinal tract include the mouth, pharynx, esophagus, stomach, small intestine, and large intestine. The associated glands include salivary glands, liver, gallbladder, and pancreas.

Chapter 32.4, Problem 3CC

Summary Introduction

To evaluate: The statement that the “Cambrian explosion actually consists of three explosions, not one.”

Concept introduction:

Cambrian explosion refers to the rapid diversification of animals that occurred 535-525 million years ago, during the Paleozoic era. Simple, soft bodied animals also called Ediacaran fauna inhabited the earth before the Cambrian explosion. There are various hypotheses that explain the Cambrian explosion.

According to one hypothesis, the appearance of a prey-predator relationship led to the Cambrian explosion. The predators in the Cambrian period acquired novel adaptations for predation. This led to natural selection of prey with hard bodies. The hard bodies helped them in defense from predators.

Another hypothesis emphasizes on the increase in atmospheric oxygen. The increase in atmospheric oxygen led to the evolution of animals with high metabolic rate and larger body size.

According to another hypothesis, the **evolution of Hox genes (developmental genes) and microRNAs** led to the evolution of animals with complex bodies. The evidences of first arthropods and chordates come from the rock strata of the Cambrian period.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Answer 4

Question

Definition Definition Organ system that helps in the digestion of food by mechanical and biochemical processes. The digestive system breaks down food into simpler components that enable the body to then absorb or transport nutrients. The human digestive system includes the gastrointestinal tract or alimentary canal and the associate glands. The organs of the gastrointestinal tract include the mouth, pharynx, esophagus, stomach, small intestine, and large intestine. The associated glands include salivary glands, liver, gallbladder, and pancreas.

Chapter 32.4, Problem 3CC

Summary Introduction