
Concept explainers
Introduction:
Jawfish includes bony and cartilaginous fish. Jaws are developed from third and fourth gill arches. The development of the jaw means the appearance of teeth. With the passage of time, jaws became important for feeding. Some 420 million years old, Entelognathus primordialis may be the first vertebrae with a modern jaw. Originally the jaws help to pump the water above the gills so that the fish can breathe more perfectly. Jaws help fishes to catch larger prey.

Answer to Problem 1TY
The correct answer is option (a) gnathostomes.
Explanation of Solution
Explanation/justification for the correct answer:
Option (a) gnathostomes. They are marine fishes. Jawed fishes belong to clade Gnathostomes. Gnathostomes possess 2 sets of paired fins (i.e. pelvic fin and pectoral fin). They are enclosed with bony plates. The gill filaments are ectodermal. An enormous placoderm was Dunkleosteous from the ‘Devonian period’, 380-360 million years ago. Gnathostomes belong to the clade Chondrichthyes and Osteichthyes.
Explanation for incorrect answer:
Option (b) lobe fins. Lobe-finned fishes or Sarcopterygii is a clade that contains coelacanths, tetrapods, lungfishes, etc. Sarcopterygii are sometimes also called Crossopterygii. Lobe fins are the most important characteristics of lobe-finned fishes. Their fins are very elastic. Therefore, this is an incorrect answer.
Option (b) tetrapods. The word "Tetrapoda" means "four feet" in Greek. Reptiles, birds, amphibians, and mammals are the chief groups of the Tetrapoda. They first appeared 370 million years back during the ‘Devonian period’. Tetrapods vary in size. One of the important characteristics of tetrapods is, they bear four legs or if they do not have four limbs, their ancestors are assumed to have four limbs. Therefore, this answer is not correct.
Option (d) amniotes.The characteristic feature of amniotes is an amniotic egg. Birds, reptiles, and prototherian mammal produce an amniotic egg. The outer shell of an egg is made of hard calcium to protect it from pathogens, predators, drying, and damage. Amniotic egg contains amnion. Amnion membrane is the special feature of amniotic animals.Therefore, this answer is not correct.
Option (e) cyclostomes.Cyclostomes are jawless fishes having a large sucking mouth. They are fresh-water and marine vertebrates. Due to the absence of jaw, they are termed as jawless vertebratesTherefore, this answer is not correct.
Gnathostomes are the jawed vertebrates. Gnathostomes include two clades i.e. Chondrichthyes and Osteichthyes. Hence, the correct answer is option (a).
Want to see more full solutions like this?
Chapter 27 Solutions
Principles of Biology
- Explain down bellow what happens to the cell in pictures not in words: Decreased pH in mitochondria Increased ATP Decreased pH in cytosol Increased hydrolysis Decreasing glycogen and triglycerides Increased MAP kinase activity Poor ion transport → For each one:→ What normally happens?→ What is wrong now?→ How does it mess up the cell?arrow_forward1.) Community Diversity: The brown and orange line represent two different plant communities. a. Which color represents the community with a higher species richness? b. Which color represents the community with a higher species evenness? Relative abundance 0.1 0.04 0.001 2 4 6 8 10 12 14 16 18 20 22 24 Rank abundance c. What is the maximum value of the Simpson's diversity index (remember, Simpson's index is D = p², Simpson's diversity index is 1-D)? d. If the Simpson's diversity index equals 1, what does that mean about the number of species and their relative abundance within community being assessed?arrow_forward1.) Community Diversity: The brown and orange line represent two different plant communities. a. Which color represents the community with a higher species richness? b. Which color represents the community with a higher species evenness? Relative abundance 0.1 0.04 0.001 2 4 6 8 10 12 14 16 18 20 22 24 Rank abundance c. What is the maximum value of the Simpson's diversity index (remember, Simpson's index is D = p², Simpson's diversity index is 1-D)? d. If the Simpson's diversity index equals 1, what does that mean about the number of species and their relative abundance within community being assessed?arrow_forward
- what measures can a mother to take to improve the produce of her to milk to her newborn baby ?arrow_forward1. Color the line that represents all ancestors of the Eastern white pine tree green (but only the ancestral line NOT shared with other organisms) 2. Oncle the last common ancestor of the Colorado blue spruce tree and Eastern white pine tree. 3. Put a box around the last common ancestor of the sugar maple tree and the dogwood tree. 4. Put a triangle around the last common ancestor of the red pine tree and the american holly bush. 5. Color the line that represents all ancestors of the Ponderosa pine tree red (including all shared ancestors). 6. Color the line that represents all ancestors of the American elm tree blue (including all shared ancestors). 7 Color the line that represents all ancestors of the Sabal palm tree purple (including all shared ancestors) 8. Using a yellow highlighter or colored pencil, circle the clade that includes all pine trees. 9. Using a orange highlighter or colored pencil, circle the clade that includes all gymnosperms 10. Can you tell…arrow_forwardYou have been hired as a public relations specialist to give invertebrates a good name. After all, they are much more than just creepy crawly bugs! Your first task though is to convince yourself that is true. The best way to do that is to start close to home. Find something in your house that is a product obtained directly from an invertebrate or only due to an invertebrate’s actions. Describe the product, its function and utility, as well as any human manufactured alternatives. Be sure to highlight the advantages of obtaining this directly from nature. Keep in mind, a product can be something you use, wear, eat, or enjoy for its visual appeal.arrow_forward
- Use the following tree diagram to answer Questions #8-10. 8) Which of the following two animals are the most closely related based on the tree to the left? a) Pig and camel b) Hippo and pig c) Deer and cow 9) CIRCLE on the tree diagram where the common ancestor between a hippo and a cow is. 10) Put a SQUARE on the tree diagram where the common ancestor between a pig and a peccary is.arrow_forwardExplain: Healthy Cell Function Overview→ Briefly describe how a healthy cell usually works: metabolism (ATP production), pH balance, glycogen storage, ion transport, enzymes, etc. Gene Mutation and Genetics Part→ Focus on the autosomal recessive mutation and explain: How gene mutation affects the cell. How autosomal inheritance works. Compare the normal and mutated gene sequences simply. → Talk about possible consequences of a faulty hydrolytic enzyme.arrow_forwardCan you fill out those termsarrow_forward
- Explain down bellow what happens to the cell: Decreased pH in mitochondria Increased ATP Decreased pH in cytosol Increased hydrolysis Decreasing glycogen and triglycerides Increased MAP kinase activity Poor ion transport → For each one:→ What normally happens?→ What is wrong now?→ How does it mess up the cell?arrow_forwardAn 1100 pound equine patient was given 20 mg/kg sucralfate 3 times a day, 2.8 mg/kg famotidine twice a day, and 10mg/kg doxycycline twice a day. Sucralfate comes as a 1 gm tablet, famotidine as 20 mg tablets, and doxycycline as 100mg tablets. All are in bottles of 100 tablets.How many total mg are needed for the patient and how many tablets of each would be needed to provide each dose?How many bottles of each would be needed to have available if this patient were to be on this drug regimen for 5 days?arrow_forwardThe patient needs a solution of 2.5% dextrose in Lactated Ringer’s solution to run at 75 ml/hr for at least the next 12hours. LRS comes in fluid bags of 500 ml, 1 Liter, 3 Liters and 5 Liters. How can a 2.5% solution be made by adding50% dextrose to the LRS?arrow_forward
- Concepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax CollegeBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxBiology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage LearningBiology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage Learning





