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Honors Biology Assignments

April 20-24

Coach Erwin

903-756-5314 ext. 4109

[email protected]

OR USE THE REMIND APPJoin the Remind Group

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Assignments for the week are focused on vertebrate animals and their characteristics. Read the material carefully to identify specifics traits! The review assignment for the week goes back to comparisons of aerobic and anaerobic processes such as photosynthesis and cellular respiration. Use the review sheet to recall important information about these processes!

If you have any questions use the remind app to ask!

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© Houghton Mifflin Harcourt Publishing Company.

Holt McDougal Biology 1 Vertebrate Diversity

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Name:_______________________________Class:___________________Date:____________________

HONORS Assignments April 20-24

MONDAY

Review and edit last week’s assignments if necessary. Those assignments are due by Wednesday.

TUESDAY (USE REVIEW PAGE)

1. What are some factors that affect enzyme function?2. We refer to organisms that carry out photosynthesis as _______________.3. Chemosynthesis occurs in organisms that live where?4. Energy from aerobic respiration is used to make what molecule?5. Light is required for what process?6. Enzymes can also be referred to as what kind of molecule?

WEDNESDAY

Active Reading and Data Analysis Activities

THURSDAY (USE REVIEW PAGE)

1. What molecules are largely responsible for building new cells?2. What process occurs in all living things?3. What kind of organisms use the process of chemosynthesis?4. What sugar is broken down during cellular respiration?5. The organisms that carry out chemosynthesis are referred to as _______________.6. Carbon dioxide is taken in during what process?

FRIDAY

Pre-AP Activity “Poison Dart Frogs and Their Toxins”



Name:_______________________________Class:___________________Date:____________________

Poison Dart Frogs and Their Toxins

Pre-AP ActivityIn Chapter 25, you have learned that some tropical frogs make toxins to protect themselves from predators. The most poisonous type of frogs, the poison dart frogs, make up the family Dendrobatidae. Different types of toxins are found in these frogs. In this activity you will learn about several of these toxins and how scientists think the frogs acquire them.

FAMILY DENDROBATIDAEPoison dart frogs, known for their bright coloration and toxic secretions, are found throughout the tropical regions of Central and South America. There are eight genera and less than 200 species of these frogs, with the greatest diversity occurring in the northwestern regions of South America. Poison dart frogs have cutaneous granular glands that are scattered over their bodies. When a frog is threatened, toxins are secreted from these glands onto their skin. These toxins are alkaloids, organic compounds that contain nitrogen. There are more than 500 different types of alkaloids that can be secreted. If a predator comes into contact with a toxin, the reaction can range from mild (numbness) to severe (death). Most toxins secreted by poison dart frogs are neurotoxins, which affect nerve transmission and the contraction of muscle cells. Two such toxins, which are also the two most poisonous, are batrachotoxins and pumiliotoxins.

BATRACHOTOXINSThis type of toxin is commonly found in poison dart frogs belonging to the genus Phyllobates. Batrachotoxins increase the permeability of the outer membrane of nerve and muscle cells, allowing more sodium ions to enter. This prevents nerve cells from signaling muscle cells to relax. The muscle cells stay contracted, which can lead to heart arrhythmias, convulsions, heart failure, and death. The Emberá and Noanamá Chocó Indians of western Colombia have used batrachotoxins secreted from frogs to poison the darts used in their blowguns, hence the common name of these frogs. Batrachotoxins are among the world’s most deadliest substances and there is no antidote.

One of the most poisonous animals on Earth is Phyllobates terribilis, the golden poison frog. One individual contains between 700 to 1900 µg of batrachotoxins. The minimum lethal dose required to kill a 20 g mouse is 0.05 µg, meaning one frog contains enough toxin to kill more than 20,000 mice. In comparison, the minimum lethal dose required to kill a 68 kg (150 pound) human is 136 µg. This means that one frog has enough toxin to kill ten humans. The only known predator of P. terribilis is the snake Leimadopis epinephelus, which is immune to batrachotoxins.



Name:_______________________________Class:___________________Date:____________________

Pre-AP Activity continued

PUMILIOTOXINSPumiliotoxins are found in poison dart frogs belonging to the genus Phyllobates and Dendrobates and are 100 to 1000 times less toxic than batrachotoxins. There are more than 100 pumiliotoxins that are classified into three groups: Pumiliotoxins A, B, and C. These toxins are not yet fully understood, but it is thought that they affect calcium and sodium–dependent processes in nerve and muscle cells, thereby causing problems with movement. Pumiliotoxins belonging to groups A and B are more toxic than those in group C. When 100 g of pumiliotoxin A or B are injected into mice, restricted movement, convulsions, partial paralysis, and death can occur.

TOXIC DIETScientists have been researching how the poison dart frogs acquire the toxins they secrete. It appears as if the frogs’ diet may have something to do with it. By eating formicine ants and other invertebrates that are rich in alkaloids, the frogs are able to accumulate pumiliotoxins and store them in their skin. This conclusion was reached after studies were conducted using frogs raised in captivity. One group of captive frogs were fed a diet of fruit flies and crickets, which lack alkaloids. Over time, those frogs lost the ability to secrete toxins. Another group of captive frogs were fed a diet of invertebrates collected from their native leaf litter. These frogs were able to secrete toxins. Other studies have shown that at least three species of Dendrobates frogs can modify alkaloids gained through food sources and make them five times as poisonous.

It may also be possible that poison dart frogs can manufacture toxins independently. Batrachotoxins are not known to exist in any other animal except for the hooded pitohui bird of New Guinea. These toxins are not found in the poison dart frogs’ diet, which leads scientists to believe that the frogs may produce some poisons internally.1. Compare the defense mechanisms used by poison dart frogs to that of non–poisonous

frogs.________________________________________________________________________________________________________________________________



Name:_______________________________Class:___________________Date:____________________

Pre-AP Activity continued

2. From an evolutionary perspective, describe a sequence of selection events that would lead to the bright, warning coloration that is now characteristic of poison dart frogs. Assume that at one time, both poisonous frogs and non–poisonous frogs had the same dull coloration.

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

3. Epibatidine is a rare alkaloid secreted by the phantasmal poison frog, Epipedobates tricolor. This alkaloid has been shown to be 200 times more potent than morphine, a painkiller. Why do you think medical scientists might be very interested in researching frog toxins? Explain.

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ACTIVE READING WORKSHEETS

FISHES© Houghton Mifflin Harcourt Publishing Company.


Name:_______________________________Class:___________________Date:____________________

Jawless and Cartilaginous FishesRead the passage below, which covers topics from your textbook. Answer the questions that follow.

1 Cartilaginous fishes differ from jawless fishes in that fertilization occurs inside the body of the female. 2 This type of fertilization is called internal fertilization. 3 During mating, the male transfers sperm into the female’s body with modified pelvic fins called claspers. 4 In a few species of sharks and rays, the females lay large yolky eggs right after fertilization. 5 The young develop within the egg, are nourished by the yolk, and hatch as miniature versions of the adults. 6 The eggs of many species develop in the female’s body, and the young are born live. 7 In some of these species, the mother nourishes the developing sharks while they are in her body. 8 No cartilaginous fishes provide parental care for their young after birth or hatching.

Read each question and write your answer in the space provided.SKILL: Recognizing Text Structure1. When items are compared, similarities between them are noted. When items are

contrasted, dissimilarities or differences are noted. What trait of cartilaginous and jawless fishes is being contrasted in Sentence 1?________________________________________________________________

2. What is the similarity or difference of cartilaginous fishes identified in Sentence 8?________________________________________________________________

Circle the letter of the phrase that best completes the sentence.3. In some species of cartilaginous fishes, the mother nourishes her developing sharks

a. after they hatch from eggs.b. after they are born live.c. while they are inside her body.d. Both (a) and (b)



Name:_______________________________Class:___________________Date:____________________

ACTIVE READING WORKSHEETS

AMPHIBIANS

Characteristics of AmphibiansRead the passage below, which covers topics from your textbook. Answer the questions that follow.

The amphibian digestive system includes the pharynx, esophagus, stomach, liver, gallbladder, small intestine, large intestine, and cloaca. The elastic esophagus and stomach allow an amphibian to swallow large amounts of food. Once food reaches the stomach, tiny glands in the stomach walls secrete gastric juices that help break down, or digest, the food. A muscle called the pyloric sphincter at the lower end of the stomach relaxes, which allows digested food to move into the small intestine. The upper portion of the small intestine is called the duodenum. The coiled middle portion of the small intestine is the ileum. A membrane resembling plastic wrap, called the mesentery, holds the small intestine in place. Inside the small intestine, digestion is completed and the released nutrients pass through capillary walls into the bloodstream, which carries them to all parts of the body.

The lower end of the small intestine leads into the large intestine. Here indigestible wastes are collected and pushed by muscle action into a cavity called the cloaca. Waste from the kidneys and urinary bladder, as well as either eggs or sperm from the gonads, also passes into the cloaca. Waste materials exit the body through the vent.

Write the name of digestive organ described on the line provided.SKILL: Vocabulary Development

_________________________ 1. where waste materials exit the body

_________________________ 2. where digestion is completed

_________________________ 3. the organ in which glands in the walls secrete gastric juices

_________________________ 4. where indigestible materials are collected after leaving the small intestine

_________________________ 5. holds the small intestine in place

_________________________ 6. the organ into which eggs or sperm from the gonads may pass



Name:_______________________________Class:___________________Date:____________________

Write your answers in the spaces provided.

Read the question and write your answer in the space provided.SKILL: Vocabulary Development8. The prefix in- often means “not,” while the suffix -ible means “able to do or make.” How

does knowledge of these word parts aid in decoding the term indigestible?________________________________________________________________________________________________________________________________

Circle the letter of the word or phrase that best completes the analogy.9. Small intestine is to duodenum as stomach is to

a. pyloric sphincter. c. esophagus.b. vent. d. cloaca.



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