Lecture 1 & 2: Vertebrate origins Flashcards
What are the 5 chordate features?
- notochord
- pharyengeal slits
- Endostyle
- Nerve cord
- Postanal tail
Which of the following structures in chordates assists in filter feeding and iodine metabolism?
A) Pharyngeal slits
B) Endostyle
C) Notochord
D) Postanal tail
B) Endostyle
Which part of the nerve chord in chordates is dorsal to the gut?
A) Pharyngeal slits
B) Endostyle
C) Nerve chord
D) Postanal tail
C) Nerve chord
Which of the following classes within the subphylum Chordata includes animals with a skull?
A) Tunicates
B) Cephalochordata
C) Craniata
D) Agnatha
c) Craniata
Tunicates are also known as:
A) Sea squirts
B) Lancelets
C) Lampreys
D) Hagfish
A) Sea squirts
Which of the following chordates is characterized by a notochord extending through most of its body length?
A) Craniata
B) Tunicates
C) Cephalochordata
D) Agnatha
c) Cephalachordata
Vertebrates in the class Craniata are characterized by the presence of:
A) A notochord
B) A dorsal hollow nerve cord
C) A segmented body
D) A skull enclosing the brain
D) A skull enclosing the brain
How do cephalochordates facilitate blood circulation in their circulatory system?
A) Through the contraction of the hepatic vein
B) Through the pumping action of a heart
C) By the contractions of the ventral aorta and other vessels
D) Through the rhythmic expansion and contraction of bulbili
A) through the contractions of the ventral aorta and other vesseles like the hepatic vein
- they have no heart
Which of the following statements about tunicates is true regarding their circulatory system?
A) Tunicates lack a circulatory system altogether.
B) Tunicates possess a highly developed heart with multiple chambers.
C) Tunicates have a rudimentary heart that aids in circulation.
D) Tunicates rely solely on diffusion for the transport of nutrients and gases.
C) Tunicates (Urochordates) have a rudimentary heart helping in circulation
Which of the following developments in protochordates led to the evolution of vertebrates, driven by food-related reasons?
A) Strengthening of the tail for enhanced locomotion
B) Reduction of the pharynx to simplify feeding
C) Evolution of simple gills to support increased respiratory demands
D) Expansion of body size for better predator avoidance
c) evolution of gills to support increased respiratory demands for more active feeding lifestyle
Which two developments were critical for the evolution of Craniata, distinguishing them from other chordates?
A) Strengthening of the tail for enhanced locomotion and reduction of the pharynx to simplify feeding
B) Evolution of paired fins for improved maneuverability and development of a ventral nerve cord
C) Development of a vertebral column and a protective cranium around the brain
D) Strengthening of the pharynx for improved respiration and expansion of body size for better predator avoidance
c) Development of the vertebral coloumn and a protective cranium around the brain
Which of the following groups are considered living agnathans?
A) Placoderms
B) Bony fish
C) Cyclostomes
D) Ostracoderms
c) Cyclostomes (Hagfish/Lamprey)
Which group of extinct jawless fish is characterized by a median nostril?
A) Acanthodians
B) Placoderms
C) Ostracoderms
D) Conodonts
C) Ostracoderms (extinct)
What common feature do ostracoderms and cyclostomes share?
A) Paired fins
B) Median nostril
C) Bony skeleton
D) Internal gills
b) median nostril
