Bio1331 Animals - Evolution - Origins Of Invertebrates (Lecture One)
You should be able to: Demonstrate understanding of the proposed origins of the invertebrates
Questions and Answers
- 1.
What is the simple definition of an invertebrate?
- A.
An animal without a backbone
- B.
An animal with a backbone
- C.
An animal without a notochord
- D.
An animal with a notochord
Correct Answer
A. An animal without a backboneExplanation
The correct answer is "An animal without a backbone." This definition accurately describes an invertebrate, which is a type of animal that does not possess a backbone or vertebral column. Invertebrates make up the majority of the animal kingdom and include various groups such as insects, worms, mollusks, and arachnids.Rate this question:
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- 2.
What evidence can be used to provide clues to the relatedness of a species to others?e.g. using molecules and gene sequences
Correct Answer
Fossils
Looking at fossils
A fossil
Morphology
Morphology of extant animals
Physiology
Physiology of extant animals
Morphology and physiology
Morphology and physiology of extant animals
Embryonic development
EmbryosExplanation
The evidence that can be used to provide clues to the relatedness of a species to others includes fossils, morphology (both of extant animals and their physiology), and embryonic development. Fossils can provide information about the physical characteristics of extinct species and how they may be related to current species. Morphology refers to the study of the form and structure of organisms, and comparing the morphology of different species can reveal similarities and differences that may indicate relatedness. Similarly, studying the physiology of extant animals can provide insights into their evolutionary relationships. Finally, examining embryonic development can help identify similarities in the early stages of different species, suggesting a common ancestry.Rate this question:
- 3.
Animals are ________, because they digest outside nutrients and have a gut.
Correct Answer
HeterotrophsExplanation
Animals are classified as heterotrophs because they rely on external sources for obtaining nutrients. Unlike autotrophs, which can produce their own food through photosynthesis, animals cannot synthesize organic molecules and must consume other organisms or their byproducts to obtain energy. The mention of having a gut further supports this classification, as animals possess specialized digestive systems that allow them to break down and absorb nutrients from the food they consume.Rate this question:
- 4.
Name the putative animal ancestor.
Correct Answer
The choanoflagellate
The choanoflagellates
Choanoflagellate
ChoanoflagellatesExplanation
The correct answer is "choanoflagellate" or "choanoflagellates." Choanoflagellates are considered to be the putative animal ancestor because they share many similarities with animals, particularly in the structure and function of their flagella and collar cells. These similarities suggest a close evolutionary relationship between choanoflagellates and animals, making choanoflagellates a potential ancestor of animals.Rate this question:
- 5.
Which of the following is true for the putative animal ancestor Choanoflagellate?You may choose more than one.
- A.
Has actin collar for prey capture
- B.
Has flagellum for movement
- C.
Is multicellular
- D.
Is single-cellular but exists in colonies
- E.
Has a cell wall
- F.
Has capsule similar to bacteria
Correct Answer(s)
A. Has actin collar for prey capture
B. Has flagellum for movement
D. Is single-cellular but exists in coloniesExplanation
The putative animal ancestor Choanoflagellate has an actin collar for prey capture, which helps it capture food. It also has a flagellum for movement, allowing it to swim and navigate through its environment. Although it is single-cellular, it can exist in colonies, forming a group of cells that work together. However, it is not multicellular, meaning it does not consist of multiple specialized cells. It does not have a cell wall, which is a rigid outer layer found in many organisms. It also does not have a capsule similar to bacteria, which is a protective layer.Rate this question:
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- 6.
When did the choanoflagellates arise?
- A.
>600 million years ago
- B.
>600 thousand years ago
- C.
>1 billion years ago
- D.
>1 million years ago
Correct Answer
A. >600 million years agoExplanation
Choanoflagellates are a group of single-celled organisms that are considered the closest living relatives of animals. Fossil evidence suggests that choanoflagellates arose over 600 million years ago, making them one of the oldest known groups of eukaryotic organisms. This early emergence is significant because it provides insights into the evolutionary history of animals and their transition from single-celled to multicellular organisms. Therefore, the correct answer is ">600 million years ago."Rate this question:
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- 7.
Complete the following sentence:Choanoflagellates are morphologically similar to ________ cells found in sponges, associated with assisting water flow through the sponge.
Correct Answer
Choanocyte
Choanocytes
The choanocyteExplanation
Choanoflagellates are morphologically similar to choanocyte cells found in sponges, associated with assisting water flow through the sponge. Choanocytes are specialized cells that have a collar of microvilli surrounding a flagellum, resembling the structure of choanoflagellates. These cells create water currents by beating their flagella, which helps in capturing food particles and maintaining water flow through the sponge's body. The similarity in morphology suggests a possible evolutionary relationship between choanoflagellates and choanocytes in sponges.Rate this question:
- 8.
Complete the following sentence:The choanoflagellate M. brevicollis shares animal receptor ___________ genes associated with intercellular signalling.
Correct Answer
Tyrosine kinaseExplanation
The choanoflagellate M. brevicollis shares animal receptor tyrosine kinase genes associated with intercellular signaling. This suggests that these genes have been conserved throughout evolution and play a crucial role in cellular communication and signaling pathways. Tyrosine kinases are enzymes that phosphorylate tyrosine residues on proteins, thereby regulating their activity and initiating downstream signaling cascades. The presence of these genes in M. brevicollis indicates that they may have been present in the common ancestor of animals and choanoflagellates, highlighting their importance in cellular communication processes.Rate this question:
- 9.
Complete the following sentence:Animals are _________, meaning they are related to, descending from or derived from one source.
Correct Answer
MonophyleticExplanation
Animals are monophyletic, meaning they are related to, descending from, or derived from one source. This term refers to a group of organisms that includes a common ancestor and all of its descendants. In the case of animals, it signifies that all animals share a common ancestor and have evolved from it over time. This concept is crucial in understanding the evolutionary relationships and classification of different animal species.Rate this question:
- 10.
Name the ancient life form resembling jellyfish, corals and worms that appeared approx 610 million years ago, often described as a 'failed experiment' in multicellular life.
Correct Answer
Ediacaran biota
E biota
E. biotaExplanation
The correct answer is Ediacaran biota, E biota, E. biota. The Ediacaran biota refers to a group of ancient life forms that appeared approximately 610 million years ago. These organisms resembled jellyfish, corals, and worms. They are often described as a "failed experiment" in multicellular life because they existed for a relatively short period of time and did not give rise to any modern-day descendants. The term "E biota" and "E. biota" are abbreviations for Ediacaran biota.Rate this question:
- 11.
Complete the following sentence:The _________ explosion was a period of rapid evolution of novel morphologies within a few million years.
Correct Answer
CambrianExplanation
The Cambrian explosion refers to a time period in Earth's history, approximately 541 million years ago, when there was a sudden and rapid diversification of life forms. During this period, a wide range of novel morphologies and body plans evolved within a relatively short span of time, which greatly contributed to the development of complex organisms. This explosion of life forms in the Cambrian period laid the foundation for the subsequent evolution and diversity of life on Earth.Rate this question:
- 12.
True or False?Marine environments have salinity levels of approximately 3.5%.
- A.
True
- B.
False
Correct Answer
A. TrueExplanation
Marine environments, such as oceans and seas, have salinity levels of approximately 3.5%. This means that for every 1,000 grams of water, about 35 grams are dissolved salts. The high salinity is due to the continuous input of salts from rivers and the evaporation of water, leaving behind the dissolved salts. This salinity level is important for the survival of marine organisms, as it affects their osmoregulation and overall physiological processes.Rate this question:
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- 13.
Which habitat type harbours the greatest biodiversity and abundance of invertebrates?
- A.
Marine
- B.
Freshwater
- C.
Terrestrial
- D.
Salt marshes and mangrove swamps
- E.
Estuaries
Correct Answer
A. MarineExplanation
Marine habitats are known to harbor the greatest biodiversity and abundance of invertebrates. This is because the marine environment provides a wide range of niches and habitats for various species to thrive. The vastness of the oceans and the diverse ecosystems within them, such as coral reefs, seagrass beds, and deep-sea habitats, offer a rich and diverse array of food sources and shelter for invertebrates. Additionally, the constant movement of water in marine habitats ensures a steady supply of nutrients, further supporting the growth and abundance of invertebrate populations.Rate this question:
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- 14.
Complete the following sentence:A _______ is an immature life stage that differs from the adult.
Correct Answer
LarvaeExplanation
A larvae is an immature life stage that differs from the adult. Larvae are typically found in insects and other animals that undergo metamorphosis. They often have different physical characteristics and behaviors compared to the adult form. During this stage, larvae undergo significant growth and development before eventually transforming into the adult form.Rate this question:
- 15.
Complete the following sentence:___________ is when characteristics of one life stage improve the ability for one activity but reduce performance in others.
Correct Answer
Trade-off
Trade offExplanation
A trade-off is a situation in which the characteristics of one life stage enhance the ability to perform a specific activity but at the same time hinder performance in other activities. It refers to the concept of making a compromise or sacrificing one thing in order to gain something else. In this context, it implies that there is a trade-off between the advantages gained in one area and the disadvantages experienced in another area due to the characteristics of a particular life stage.Rate this question:
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Mar 19, 2023Quiz Edited by
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Nov 23, 2015Quiz Created by
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