
Concept explainers
Deathly Lamprey Repellent Predation by sea lampreys on native fishes in the Great Lakes is an ongoing problem. To help solve it, Michael Wagner and his team test methods of repelling lampreys. They carried out an experiment to investigate reports that sea lampreys detect the scent of lamprey carcasses and tend to avoid them. The researchers made alcohol-based lamprey carcass extracts, then observed what happened when lampreys were put in tanks and exposed to either this extract or to alcohol alone. FIGURE 25.6 shows their results.
FIGURE 25.6 Effectiveness of carcass extracts as a lamprey repellent.
Mean proportion of lampreys on the scented side of the test tank during B trials with 10 lampreys. Lampreys were placed in the tank for 20 minutes before exposure to alcohol or carcass extract and remained there for 40 minutes after exposure. The upper graph shows results with alcohol as the stimulus; the lower shows the results with carcass extracts. Bars indicate standard error.
Why was it necessary to test the response of lampreys to the scent of alcohol alone?

To explain: The reason why it is necessary to test the response of lampreys to the scent of the alcohol alone
Concept introduction: Sea lampreys are chordates that are classified as jawless fishes and are major parasitic carnivorous chordates. The sea lampreys are pests in the Great lakes of the USA as they cause loss of several commercial fishes.
Explanation of Solution
In order to reduce the menace of the lampreys, Scientist M and his team designed an experiment to investigate and report that sea lampreys detect the scent of other lamprey carcasses and have the nature to avoid them. The team used alcohol-based extracts of lamprey carcasses. They then observed the results when lampreys were put in two tanks: one with the alcohol-based extract and another with alcohol alone.
The alcohol serves as a control. The lampreys should not have any reaction towards alcohol as they are the additional substance present along with the tissue extract of lamprey carcass. Therefore, it is necessary to confirm that lampreys are not attracted to the scent alcohol.
The lampreys exposed to alcohol alone in the tank will help us to confirm if the lampreys are attracted to the carcass alone or both alcohol and carcass combined.
Want to see more full solutions like this?
Chapter 25 Solutions
Biology: The Unity and Diversity of Life (MindTap Course List)
Additional Science Textbook Solutions
SEELEY'S ANATOMY+PHYSIOLOGY
General, Organic, and Biological Chemistry - 4th edition
Introductory Chemistry (6th Edition)
Chemistry: Atoms First
Genetics: From Genes to Genomes
- What is a gain of function mutation?arrow_forwardMolecular Biology Question: Please help. Thank you Is Southern hybridization's purpose detecting specific nucleotide sequences? How so?arrow_forwardUse the following information to answer the question(s) below. Martin Wikelski and L. Michael Romero (Body size, performance and fitness in Galápagos marine iguanas, Integrative and Comparative Biology 43 [2003]:376-86) measured the snout-to-vent (anus) length of Galápagos marine iguanas and observed the percent survival of different-sized animals, all of the same age. The graph shows the log snout-vent length (SVL, a measure of overall body size) plotted against the percent survival of these different size classes for males and females. Survival (%) 100- 80- 60- 40- 20- 0+ 1.9 T 2 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Log SVL (mm) 19) Examine the figure above. What type of selection for body size appears to be occurring in these marine iguanas? A) directional selection B) stabilizing selection C) disruptive selection D) You cannot determine the type of selection from the above information. 3arrow_forward
- 24) Use the following information to answer the question below. Researchers studying a small milkweed population note that some plants produce a toxin and other plants do not. They identify the gene responsible for toxin production. The dominant allele (T) codes for an enzyme that makes the toxin, and the recessive allele (t) codes for a nonfunctional enzyme that cannot produce the toxin. Heterozygotes produce an intermediate amount of toxin. The genotypes of all individuals in the population are determined (see table) and used to determine the actual allele frequencies in the population. TT 0.49 Tt 0.42 tt 0.09 Refer to the table above. Is this population in Hardy-Weinberg equilibrium? A) Yes. C) No; there are more homozygotes than expected. B) No; there are more heterozygotes than expected. D) It is impossible to tell.arrow_forward30) A B CDEFG Refer to the accompanying figure. Which of the following forms a monophyletic group? A) A, B, C, and D B) C and D C) D, E, and F D) E, F, and Garrow_forwardMolecular Biology Question. Please help with step solution and explanation. Thank you: The Polymerase Chain Reaction (PCR) reaction consists of three steps denaturation, hybridization, and elongation. Please describe what occurs in the annealing step of the PCR reaction. (I think annealing step is hybridization). What are the other two steps of PCR, and what are their functions? Next, suppose the Tm for the two primers being used are 54C for Primer A and 67C for Primer B. Regarding annealing step temperature, I have the following choices for the temperature used during the annealing step:(a) 43C (b) 49C (c) 62C (d) 73C Which temperature/temperatures should I choose? What is the corresponding correct explanation, and why would I not use the other temperatures? Have a good day!arrow_forward
- Using the data provided on the mean body mass and horn size of 4-year-old male sheep, draw a scatterplot graph to examine how body mass and horn size changed over time.arrow_forwardPlease write a 500-word report about the intake of saturated fat, sodium, alcoholic beverages, or added sugar in America. Choose ONE of these and write about what is recommended by the Dietary Guidelines for Americans (guideline #4) and why Americans exceed the intake of that nutrient. Explain what we could do as a society and/or individuals to reduce our intake of your chosen nutrient.arrow_forwardWrite a 500-word report indicating how you can change the quantity or quality of TWO nutrients where your intake was LOWER than what is recommended by the Dietary Guidelines for Americans and/or the DRIs. Indicate how the lack of the nutrient may affect your health. For full credit, all of the following points must be addressed and elaborated on in more detail for each nutrient: The name of the nutrient At least 2 main functions of the nutrient (example: “Vitamin D regulates calcium levels in the blood and calcification of bones.”) Your percent intake compared to the RDA/DRI (example “I consumed 50% of the RDA for vitamin D”) Indicate why your intake was below the recommendations (example: “I only had one serving of dairy products and that was why I was below the recommendations for vitamin D”) How would you change your dietary pattern to meet the recommendations? – be sure to list specific foods (example: “I would add a yogurt and a glass of milk to each day in order to increase my…arrow_forward
- Why are nutrient absorption and dosage levels important when taking multivitamins and vitamin and mineral supplements?arrow_forwardI'm struggling with this topic and would really appreciate your help. I need to hand-draw a diagram and explain the process of sexual differentiation in humans, including structures, hormones, enzymes, and other details. Could you also make sure to include these terms in the explanation? . Gonads . Wolffian ducts • Müllerian ducts . ⚫ Testes . Testosterone • Anti-Müllerian Hormone (AMH) . Epididymis • Vas deferens ⚫ Seminal vesicles ⚫ 5-alpha reductase ⚫ DHT - Penis . Scrotum . Ovaries • Uterus ⚫ Fallopian tubes - Vagina - Clitoris . Labia Thank you so much for your help!arrow_forwardRequisition Exercise A phlebotomist goes to a patient’s room with the following requisition. Hometown Hospital USA 125 Goodcare Avenue Small Town, USAarrow_forward
- Biology: The Unity and Diversity of Life (MindTap...BiologyISBN:9781305073951Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa StarrPublisher:Cengage LearningBiology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage Learning


