
Concept explainers
Introduction: The most advanced placental mammals are the primates. Primates are mammals that lead an arboreal mode of life, except humans who lead terrestrial mode of life. They evolved during the Cenozoic era. The primate evolution began from Africa and there are several excavated evidences to support this theory.

Answer to Problem 1TYU
Correct answer: The first primates evolved from shrew-like placental mammals. Hence, the correct answer is option (c).
Explanation of Solution
Reasons for the correct answer:
Evolution of animals is often explained with the help of fossil evidences, body structure, and DNA analysis of fossils. Based on the available evidences, paleontologists hypothesize that shrew-like placental mammals are the immediate ancestors of the first primates that evolved. The earliest known primate is Plesiadapis, which shares several features with shrews.
Option (c) is given as “shrewlike placental mammals”.
The first primates shared several features with the shrews; hence, they are said to have evolved from shrew-like placental mammals. Thus, the correct answer is option (c).
Reasons for incorrect answers:
Option (a) is given as “shrewlike monotremes”.
Shrewlike monotremes are not the ancestors of the first primates. Montremes are not placental mammals. Primates are placental mammals. Hence, option (a) is incorrect.
Option (b) is given as “therapsids”.
Therapsids gave rise to the first mammals. They are not the direct ancestors of primates. Shrew-like placental mammals are the direct ancestors of the primates. Hence, option (b) is incorrect.
Option (d) is given as “tarsiers”.
Tarsiers are not the first primates. They are the second level of primates to have evolved. Tarsiers evolved from Simians. Hence, option (d) is incorrect.
Option (e) is given as “shrewlike marsupials”.
Shrewlike marsupials are not the ancestors of the first primates. Marsupials are not placental mammals. Primates are placental mammals. Hence, option (e) is incorrect.
Hence, options (a), (b), (d), and (e) are incorrect.
The first primates shared several features with the shrews; hence, they are said to have evolved from shrew-like placental mammals.
Want to see more full solutions like this?
Chapter 22 Solutions
Biology (MindTap Course List)
- Mutations Here is your template DNA strand: CTT TTA TAG TAG ATA CCA CAA AGG 1. Write out the complementary mRNA that matches the DNA above. 2. Write the anticodons and the amino acid sequence. 3. Change the nucleotide in position #15 to C. 4. What type of mutation is this? 5. Repeat steps 1 & 2. 6. How has this change affected the amino acid sequence? 7. Now remove nucleotides 13 through 15. 8. Repeat steps 1 & 2. 9. What type of mutation is this? 0. Do all mutations result in a change in the amino acid sequence? 1. Are all mutations considered bad? 2. The above sequence codes for a genetic disorder called cystic fibrosis (CF). 3. When A is changed to G in position #15, the person does not have CF. When T is changed to C in position #14, the person has the disorder. How could this have originated?arrow_forwardhoose a scientist(s) and research their contribution to our derstanding of DNA structure or replication. Write a one page port and include: their research where they studied and the time period in which they worked their experiments and results the contribution to our understanding of DNA cientists Watson & Crickarrow_forwardhoose a scientist(s) and research their contribution to our derstanding of DNA structure or replication. Write a one page port and include: their research where they studied and the time period in which they worked their experiments and results the contribution to our understanding of DNA cientists Watson & Crickarrow_forward
- 7. Aerobic respiration of a protein that breaks down into 12 molecules of malic acid. Assume there is no other carbon source and no acetyl-CoA. NADH FADH2 OP ATP SLP ATP Total ATP Show your work using dimensional analysis here: 3arrow_forwardFor each of the following problems calculate the following: (Week 6-3 Video with 6-1 and 6-2) Consult the total catabolic pathways on the last page as a reference for the following questions. A. How much NADH and FADH2 is produced and fed into the electron transport chain (If any)? B. How much ATP is made from oxidative phosphorylation (OP), if any? Feed the NADH and FADH2 into the electron transport chain: 3ATP/NADH, 2ATP/FADH2 C. How much ATP is made by substrate level phosphorylation (SLP)? D. How much total ATP is made? Add the SLP and OP together. 1. Aerobic respiration using 0.5 mole of glucose? NADH FADH2 OP ATP SLP ATP Total ATP Show your work using dimensional analysis here:arrow_forwardAerobic respiration of one lipid molecule. The lipid is composed of one glycerol molecule connected to two fatty acid tails. One fatty acid is 12 carbons long and the other fatty acid is 18 carbons long in the figure below. Use the information below to determine how much ATP will be produced from the glycerol part of the lipid. Then, in part B, determine how much ATP is produced from the 2 fatty acids of the lipid. Finally put the NADH and ATP yields together from the glycerol and fatty acids (part A and B) to determine your total number of ATP produced per lipid. Assume no other carbon source is available. 18 carbons fatty acids 12 carbons glycerol . Glycerol is broken down to glyceraldehyde 3-phosphate, a glycolysis intermediate via the following pathway shown in the figure below. Notice this process costs one ATP but generates one FADH2. Continue generating ATP with glyceraldehyde-3-phosphate using the standard pathway and aerobic respiration. glycerol glycerol-3- phosphate…arrow_forward
- Don't copy the other answerarrow_forward4. Aerobic respiration of 5 mM acetate solution. Assume no other carbon source and that acetate is equivalent to acetyl-CoA. NADH FADH2 OP ATP SLP ATP Total ATP Show your work using dimensional analysis here: 5. Aerobic respiration of 2 mM alpha-ketoglutaric acid solution. Assume no other carbon source. NADH FADH2 OP ATP Show your work using dimensional analysis here: SLP ATP Total ATParrow_forwardBiology You’re going to analyze 5 ul of your PCR product(out of 50 ul) on the gel. How much of 6X DNAloading buffer (dye) are you going to mix with yourPCR product to make final 1X concentration ofloading buffer in the PCR product-loading buffermixture?arrow_forward
- Write the assignment on the title "GYMNOSPERMS" focus on the explanation of its important families, characters and reproduction.arrow_forwardAwnser these Discussion Questions Answer these discussion questions and submit them as part of your lab report. Part A: The Effect of Temperature on Enzyme Activity Graph the volume of oxygen produced against the temperature of the solution. How is the oxygen production in 30 seconds related to the rate of the reaction? At what temperature is the rate of reaction the highest? Lowest? Explain. Why might the enzyme activity decrease at very high temperatures? Why might a high fever be dangerous to humans? What is the optimal temperature for enzymes in the human body? Part B: The Effect of pH on Enzyme Activity Graph the volume of oxygen produced against the pH of the solution. At what pH is the rate of reaction the highest? Lowest? Explain. Why does changing the pH affect the enzyme activity? Research the enzyme catalase. What is its function in the human body? What is the optimal pH for the following enzymes found in the human body? Explain. (catalase, lipase (in your stomach),…arrow_forwardAnwser these Discussion Questions: Part One Why were the plants kept in the dark prior to the experiment? Why is this important? Why is it important to boil the leaf? Explain why it was necessary to use boiling alcohol? What is the purpose of the iodine? Part Two What was the purpose of keeping the leaf in the dark and then covering it with a cardboard cut-out? What conclusions can you draw from this part of the lab? Part Three 7. In this experiment what was the purpose of adding the soda lime? 8. Why was a sealed bag placed around each plant? 9. What happened in the control plants? 10. What was the result on photosynthesis? Part Four 11. Why was a variegated leaf used in this experiment? !2. What conclusions can you draw about starch production in a variegated leaf?arrow_forward
- Biology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage LearningBiology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning
- Concepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax CollegeBiology: The Unity and Diversity of Life (MindTap...BiologyISBN:9781337408332Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa StarrPublisher:Cengage LearningBiology: The Unity and Diversity of Life (MindTap...BiologyISBN:9781305073951Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa StarrPublisher:Cengage Learning





