BIO 170 Final
Comprehensive Questions
with Verified Answers
Graded A+
1. Animals are typified by what kind of life cycle and early
embryological devel- opment? Answer: Most animals reproduce sexually, and the diploid
stage usually dominates the life cycle (diplontic). •
2. What are the only haploid stages in the animal life cycle? Answer:
Sperm/egg phases
3. How are sperm and egg cells produced? Answer: They are produced directly by
meiotic division
4. What colonial protists are thought to be related to the protists
giving rise to animals? Answer: A suspension feeder similar to present day
choanoflagellates.
5. What is the evidence for the choanoflagellates as being related to
the protists giving rise to animals? Answer: Collar cells, cells that adhere with
proteins homologous to animals
6. Approximately how long ago did the first animals appear? Answer: Fossil
1/
16
,steroids suggest that animals had arisen by 710 million years ago. But according to Kevin, 635
mya is the correct time.
7. In a phylogenetic sense, how are these earliest animal fossils
related to subsequent animal taxa? Answer: They are directly branched from the common
animal ancestor. Phylogenetically, these animal fossils are more primitive or more direct descendent
of the ancestors giving rise to the animals.
8. What was the Cambrian explosion? Answer: A wave of animal diversification occuring
535-525 million years ago, during the Cambrian period of the Paleozoic era. This phenomenon is
referred to as the Cambrian explosion.
• In strata that are found within this time period, paleontologists find the oldest fossils of about half of all
extant animal phyla.
9. Most of the fossils from the cambrian explosion fit into which
group? Answer: Bilaterians
10. What morphological features are employed in traditional
animal classifica- tion? Answer: Body symmetry Answer: 2 main groups
Radiata
Bilateria
11. What anatomical features are employed in traditional animal
classification?-
Answer: Embryonic germ
tissues Body cavities
12. What developmental features are employed in traditional
animal classifica- tion? Answer: Protostomal development- meaning mouth first
Deuterostome development - meaning mouth later
13. What is a coelom? Answer: The coelom is a fluid or air filled space located between
2/
16
, the digestive tract and outer body wall surrounding internal organs.
• The so called true coelom forms from tissue derived from mesoderm.
3/
16
Comprehensive Questions
with Verified Answers
Graded A+
1. Animals are typified by what kind of life cycle and early
embryological devel- opment? Answer: Most animals reproduce sexually, and the diploid
stage usually dominates the life cycle (diplontic). •
2. What are the only haploid stages in the animal life cycle? Answer:
Sperm/egg phases
3. How are sperm and egg cells produced? Answer: They are produced directly by
meiotic division
4. What colonial protists are thought to be related to the protists
giving rise to animals? Answer: A suspension feeder similar to present day
choanoflagellates.
5. What is the evidence for the choanoflagellates as being related to
the protists giving rise to animals? Answer: Collar cells, cells that adhere with
proteins homologous to animals
6. Approximately how long ago did the first animals appear? Answer: Fossil
1/
16
,steroids suggest that animals had arisen by 710 million years ago. But according to Kevin, 635
mya is the correct time.
7. In a phylogenetic sense, how are these earliest animal fossils
related to subsequent animal taxa? Answer: They are directly branched from the common
animal ancestor. Phylogenetically, these animal fossils are more primitive or more direct descendent
of the ancestors giving rise to the animals.
8. What was the Cambrian explosion? Answer: A wave of animal diversification occuring
535-525 million years ago, during the Cambrian period of the Paleozoic era. This phenomenon is
referred to as the Cambrian explosion.
• In strata that are found within this time period, paleontologists find the oldest fossils of about half of all
extant animal phyla.
9. Most of the fossils from the cambrian explosion fit into which
group? Answer: Bilaterians
10. What morphological features are employed in traditional
animal classifica- tion? Answer: Body symmetry Answer: 2 main groups
Radiata
Bilateria
11. What anatomical features are employed in traditional animal
classification?-
Answer: Embryonic germ
tissues Body cavities
12. What developmental features are employed in traditional
animal classifica- tion? Answer: Protostomal development- meaning mouth first
Deuterostome development - meaning mouth later
13. What is a coelom? Answer: The coelom is a fluid or air filled space located between
2/
16
, the digestive tract and outer body wall surrounding internal organs.
• The so called true coelom forms from tissue derived from mesoderm.
3/
16
