LET Reviewer BIOLOGICAL SCIENCE1. Humans and mice differ because A) their cells have different small organic molecules. B) their cells make different types of large biological molecules. C) their cells make different types of lipids. D) their cells have some differences in the sequence of nucleotides in their nucleic acids. E) their cells make different types of proteins.2. Why do organisms undergo molting? It is for _____. a. Growth b. Adaptation c. Locomotion d. Respiration 3. What composer the binomial nomenclature in taxonomy?a. Class and Orderb. Genus and Classc. Genus and Speciesd. Kingdom and Class4. Gymnosperms are woody plants with seeds and enclosed in fruits. An ex. is _______.a. Pine treeb. Mango treec. Acacia treed. Coconut tree

4. Which of the following field of science led to the development of Mendel's work on garden peas? a. Heredityb. Geneticsc. Biologyd. Taxonomy 5. Which of the following carbohydrates is polysaccharide?a. Glucoseb. Fructosec. Sucrosed. Starch

Molecules with which functional groups may form polymers via dehydration reactions?A) hydroxyl groups B) carbonyl groups C) carboxyl groups D) either carbonyl or carboxyl groups E) either hydroxyl or carboxyl groupsAnswer: EWhich of these molecules is not formed by dehydration reactions? A) fatty acids B) disaccharides C) DNA D) protein E) amyloseAnswer: A) In animal metabolism, most of the monomers released by digestion of food macromolecules are metabolized to provide energy. Only a small portion of these monomers are used for synthesis of new macromolecules. The net result is that A) water is generated by animal metabolism. B) water is consumed by animal metabolism. C) the water consumed is exactly balanced by the water generated, to maintain homeostasis. D) water is consumed during homeostasis, but water is generated during periods of growth. E) water is generated during homeostasis, but water is consumed during periods of growth.Answer: BWhich of these classes of biological molecules consist of both small molecules and macromolecular polymers? A) lipids B) carbohydrates C) proteins D) nucleic acids E) lipids, carbohydrates, proteins, and nucleic acids all consist of only macromolecular polymersAnswer: BWhich of the following is not a polymer? A) glucose B) starch C) cellulose D) chitin E) DNAAnswer: A

What is the chemical reaction mechanism by which cells make polymers from monomers? A) phosphodiester linkages B) hydrolysis C) dehydration reactions D) ionic bonding of monomers E) the formation of disulfide bridges between monomersAnswer: CHow many molecules of water are needed to completely hydrolyze a polymer that is 11 monomers long? A) 12 B) 11 C) 10 D) 9 E) 8Answer: CWhich of the following best summarizes the relationship between dehydration reactions and hydrolysis? A) Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers. B) Dehydration reactions eliminate water from lipid membranes, and hydrolysis makes lipid membranes water permeable. C) Dehydration reactions can occur only after hydrolysis. D) Hydrolysis creates monomers, and dehydration reactions break down polymers. E) Dehydration reactions ionize water molecules and add hydroxyl groups to polymers; hydrolysis reactions release hydroxyl groups from polymers.Answer: AWhich of the following polymers contain nitrogen? A) starch B) glycogen C) cellulose D) chitin E) amylopectinAnswer: DThe molecular formula for glucose is CH2O. What would be the molecular formula for a molecule made by linking three glucose molecules together by dehydration reactions?A) CHO B) CHO C) CHO D) C1HO E) CHOAnswer: BThe enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers are the form. Which of the following could amylase break down? A) glycogen B) cellulose C) chitin D) glycogen and chitin only E) glycogen, cellulose, and chitinAnswer: AOn food packages, to what does the term insoluble fiber refer? A) cellulose B) polypeptides C) starch D) amylopectin E) chitinAnswer: AA molecule with the chemical formula CHO is probably a A) carbohydrate. B) lipid. C) monosaccharide D) carbohydrate and lipid only. E) carbohydrate and monosaccharide only.Answer: ELactose, a sugar in milk, is composed of one glucose molecule joined by a glycosidic linkage to one galactose molecule. How is lactose classified? A) as a pentose B) as a hexose C) as a monosaccharide D) as a disaccharide E) as a polysaccharideAnswer: DAll of the following are polysaccharides exceptA) lactose. B) glycogen. C) chitin. D) cellulose. E) amylopectin.Answer: Aof the following is true of both starch and cellulose? A) They are both polymers of glucose. B) They are cis-trans isomers of each other. C) They can both be digested by humans. D) They are both used for energy storage in plants. E) They are both structural components of the plant cell wall.Answer: AWhich of the following is true of cellulose? A) It is a polymer composed of enantiomers of glucose. B) It is a storage polysaccharide for energy in plant cells. C) It is digestible by bacteria in the human gut. D) It is a major structural component of plant cell walls. E) It is a polymer composed of enantiomers of glucose, it is a storage polysaccharide for energy in plant cells, it is digestible by bacteria in the human gut, and it is a major structural component of plant cell walls.Answer: DHumans can digest starch but not cellulose because A) the monomer of starch is glucose, while the monomer of cellulose is galactose. B) humans have enzymes that can hydrolyze the glycosidic linkages of starch but not the glycosidic linkages of cellulose. C) humans have enzymes that can hydrolyze the glycosidic linkages of starch but not the glycosidic linkages of cellulose. D) humans harbor starch-digesting bacteria in the digestive tract. E) the monomer of starch is glucose, while the monomer of cellulose is glucose with a nitrogen-containing group.Answer: CWhich of the following statements concerning saturated fats is not true? A) They are more common in animals than in plants. B) They have multiple double bonds in the carbon chains of their fatty acids. C) They generally solidify at room temp

D) They contain more hydrogen than unsaturated fats having the same number of carbon atoms. E) They are one of several factors that contribute to atherosclerosis.Answer: BA molecule with the formula CH3O is probably a A) carbohydrate. B) fatty acid. C) protein. D) nucleic acid. E) hydrocarbon.Answer: BWhich of the following statements is true for the class of biological molecules known as lipids? A) They are insoluble in water. B) They are made from glycerol, fatty acids, and phosphate. C) They contain less energy than proteins and carbohydrates. D) They are made by dehydration reactions. E) They contain nitrogen.Answer: AThe label on a container of margarine lists "hydrogenated vegetable oil" as the major ingredient. What is the result of adding hydrogens to vegetable oil? A) The hydrogenated vegetable oil has a lower melting point. B) The hydrogenated vegetable oil stays solid at room temperature. C) The hydrogenated vegetable oil has more "kinks" in the fatty acid chains. D) The hydrogenated vegetable oil has fewer trans fatty acids. E) The hydrogenated vegetable oil is less likely to clog arteries.Answer: BWhich of the following is true regarding saturated fatty acids? A) They are the predominant fatty acid in corn oil. B) They have double bonds between carbon atoms of the fatty acids. C) They are the principal molecules in lard and butter. D) They are usually liquid at room temperature. E) They are usually produced by plants.Answer: CLarge organic molecules are usually assembled by polymerization of a few kinds of simple subunits. Which of the following is an exception to this statement? A) a steroid B) cellulose C) DNA D) an enzyme E) a contractile proteinAnswer: AWhich modifications of fatty acids will best keep triglycerides solid at warmer temperatures? A) creating cis double bonds to the fatty acidsB) adding hydrogens to the fatty acids C) creating trans double bonds to the fatty acids D) adding hydrogens and trans double bonds to the fatty acidsE) adding cis double bonds and trans double bonds to the fatty acidsAnswer: DWhy are human sex hormones considered to be lipids? A) They are essential components of cell membranes. B) They are not soluble in water. C) They are made of fatty acids. D) They are hydrophilic compounds. E) They contribute to atherosclerosis.Dehydration reactions are used in forming which of the following compounds? A) triacylglycerides B) polysaccharides C) proteins D) triacylglycerides and proteins only E) triacylglycerides, polysaccharides, and proteinsWhich bonds are created during the formation of the primary structure of a protein? A) peptide bonds B) hydrogen bonds C) disulfide bonds D) phosphodiester bonds E) peptide bonds, hydrogen bonds, and disulfide bondsAnswer: A

1. Which is not considered as adaptive mechanism of living things?a. Modification of body parts to suit the environment.b. Presence of specialized structures like thorns and fins.c. Possession of camouflage features like color, pattern or shape.d. Reproduction for the preservation of a certain species.

2. Biologists are at present involved in gene manipulation by altering the genes in nuclei. Which aims seem to be the most important of such manipulation?a. to cure ancient genetic diseases like cancerb. to prolong lifec. to create new types of agricultural plants and animalsd. to make significant changes in man himself

3. Which chemical substance produced by the body regulates and coordinates the functions and activities of bodily organ?a. geneb. Deoxyribonucleic acidc. hormoned. enzyme

4. Which endocrine abnormality is characterized by dwarfness, low intelligence and sex immaturity?a. myxedemab. cretinismc. tetany d. acromegaly

5. What is the present connotation of symbiosis?a. a give and take relationship of organismb. any type of relationship between two dissimilar organisms living togetherc. a one- sided relationship between two speciesd. neutral relationship that exist between two organisms

6. Living things are classified either as aerobic or anaerobic as they grow or metabolize in the presence or absence of:a. carbon dioxideb. nitrogenc. waterd. oxygen

7. What is the structural difference between plants and animals?a. Plant cells have plastids but animal cells do not.b. Plant cells have a stiff cell wall of cellulose but animal cells do not.c. Animal cells have centriole but the cells of higher plants do not.d. Plant cells have only a thin membrane but animals do not.

8. Only living things can respond to stimuli, to physical and chemical changes in their environment. Such a characteristic is called:a. metabolismb. irritabilityc. movementd. specific organization

9. The preservation of specie is made possible through:a. reproductionb. adaptationc. metabolismd. growth

10. Which process involves in the movement of dissolved molecules (solute) through a differentially permeable membrane?a. diffusionb. osmosisc. Brownian movementd. dialysis

11. Which refers to the earths entire zone of air, land and water which occupied by living things?a. biosphereb. biomec. bioassayd. biomass

12. Which body organ is responsible for the removal of waste from the blood and body fluids?a. liverb. pancreasc. kidneyd. large intestine

13. What is meant by excretion?a. Elimination of waste and undigested food from the anus.b. Removal from the cells and blood streams of substances which are no further use in the body.c. Release from the cell of some substance that is utilized elsewhere in some bodily process.d. Absorption of soluble food by the body cells.

14. The clotting of the blood is essentially the function of:a. red blood cellsb. white corpusclesc. plasmad. hemoglobin

15. All living things have a tendency to maintain uniformity or stability in their internal environment called:a. anabolismb. metabolismc. epigenesistd. homeostasis

16. What is an ecosystem?a. A basic unit that shows interaction between living things and their environment.b. A recognizable unit which shows plant and animal distribution as influenced primarily by climate.c. A fundamental unit that shows various types of relationship among organism.d. A distinct unit that shows how physical factor can affect other abiotic components in the environment.

17. Which plant structure transports organic nutrients both up and down the stem and roots?a. xylemb. vascular bundle c. parenchymad. phloem

18. Under what condition does a living organism live best or has the greatest chance of survival?a. maximalb. minimalc. optimumd. standard

19. Which traps light energy from the sun for use in the photosynthesis?a. carbon dioxideb. waterc. chlorophylld. oxygen20. Smoking cigarettes:a. causes ulcerb.decreases the vital capacity of the stomachc. leads to emphysema and lung cancerd. leads to abnormal life

21. Blood cells and plasma factors are important:a. immune defenseb. invadersc. external defensesd. internal defenses

22. A spinal nerve is:a. motor nerveb. sensory nervec. neurond. mixed nerve

23. The anterior pituitary stimulates the:a. motor coordinationb. consciousnessc. sense receptiond. homeostasis

24. What do all methods of birth control have in common?a. they all use some deviceb. they are all expensivec. they interrupt lovemakingd. they prevent the egg from coming in contact with the sperm

25. Pregnancy begins:a. upon successful implantation b. during the follicular phase c. when the egg is fertilizedd. when ovulation occurs

26. The fact that many insects are now immune to DDT is an example of:a. natural selectionb. genetic driftc. geographical isolationd. translocation

27. The nutrient glucose is useful to the body:a. to prevent goiter b. as a source of energy c. active reabsorptiond. during the process of respiration

28. Radiant energy is covered into chemical energy during:a. oxidationb. glycosisc. respirationd. photosynthesis

29. Which of the following is not a form of vegetative reproduction?a. regenerationb. buddingc. spore formationd. vegetation by runners

30. Nitrogenous waste is produced by the metabolism of:a. fats b. carbohydratesc. proteinsd. starches

31. Which of the following is a reflex act?a. breathingb. blinkingc. walkingd. sleeping

32. In an ecosystem:a. only energy is recycled b. only materials are recycled c. both materials and energy are recycledd. neither materials nor energy is recycled

33. Distribution of plants is affected by:a. type of soilb. amount of lightc. amount of rainfalld. A, B, and C are correct

34. Which decoction contains traces of iron to arrest hemorrhage?a. corn silkb. ampalaya leaves flowersc. gumamelad. coconut milk

35. Hyperacidity can destroy the lining of the stomach. Which of the following substance can ease the discomfort?a. water therapyb. milk of magnesiac. starch solutiond. gelatin

36. Deficiency of carbohydrates is characterized by:a. sluggishnessb. pallorc. obesityd. bone deformation

37. Salt as a preservative causes:a. cell shrinkageb. ionizationc. hydrolysisd. hydration

38. What do you call the practical or industrial application based on scientific principles?a. scientific methodb. technologyc. theory d. experimentation

39. What is the principal cause of earthquakes?a. faulting b. landslidesc. nuclear explosionsd. volcanic eruptions

40. Purification of metals can be done best by:a. filtration b. flotationc. aerationd. electrolysis

b. answers B, C, and Dc. Social Learningd. Behavioristic Learning

8. Usually, children learn mainly by observation. By doing this, they can get the information they need and incorporate it in the schemata. Which theory of learning is observed?a. Cognitive learningb. Humanistic learningc. Social learningd. Behavioristic learning

9. By and large educational authorities agree that character is caught and not taught. What is the rationale for this?a. Character is generally dependent on reasoning and intelligent thinkingb. Character is inborn and therefore it resists changesc. Character is generally dependent on what are seen and experiencedd. Character is developed through the process of trial and error

10. Miss X gives this activity to her pupils for ten minutes after the discussion of a lesson to help them transfer new information into long- term memory and relate them with the old lessons. What do you call this activity?a. drillb. practicec. motivationd. review

11. If a teacher discovers a mathematically- gifted child in her class, what best arrangements will be observed?a. provide him with enrichment activitiesb. let him teach the slow learnersc. place him in a special classd. accelerate him to the next grade level

12. Accordingly, one of the disadvantages of the recitation strategy is that it does not encourage understanding of information. How can the teachers improve the strategy?a. ask many questions about the topicb. ask thought- provoking questionsc. assign study topics beforehandd. give students time to think before answering

13. Generally before planning activities and experiences for his class, what would the teacher do first?a. give a diagnostic testb. identify the resources of the communityc. consult the principal about his classd. review the past lesson

14. Which of the following activities should a teacher vide to his pupils who need more practice to learn the skills?a. reviewb. practicec. drilld. seatwork

15. If you recall, there are four variables in the teaching learning process: the teacher, the nature of the subject matter, the learner and thea. referencesb. materials to usec. learning processd. objectives

16. Miss W reviews past lessons before introducing the new. She tries to establish continuity in learning and obviously she upholds s the principle of ___________.a. cause and effectb. motivationc. retentiond. apperception

17. Logically a teacher delegates some of her responsibilities to the whole class. He has an attendance monitor, pupils in charge of distributing and collecting materials. The teacher is good ina. classroom managementb. application of theoriesc. development of valuesd. instructional planning

18. The teacher who maintains disciplines and sustains interest of the students in spite of the big number of pupils in her class is said to be skilled in the ______________ aspect of classroom management.a. group focusb. movement managementc. with- itd. overlapping activities

19. All of the following are characteristics of a good question excepta. requires brief and direct answersb. stimulates students to thinkc. calls for straightforward responsed. appropriate to its purpose

20. In solving problems in Mathematics, at times these questions are asked: What is given? What is asked? and What process will you use? These type of questions area. diagnosticb. thought- provokingc. recalld. analytical

21. Logically, how can a teacher maintain the standard of quality and effectiveness of audio- visual materials in her room?a. by following closely the correct procedure in presenting themb. by constantly using them whenever possiblec. by having various types of materialsd. by continuously evaluating the revising materials

22. It is stated that audio- visual aids complement teaching to make perception more quickly and clearly. Why?a. they present programmed informationb. they present multi- sensory experiencec. they provide verbal and symbolic experiencesd. they make information readily available

23. A new teacher wants to prepare instructional material focusing informal activities with goals, rules and rewards. Which of the following can she prepare without necessarily spending money?a. puppetsb. gamesc. drawingsd. plays

14. The first task in the selection of media in teaching is to determine thea. choice of the studentsc. techniques to be usedb. availability of the mediad. strategies and techniques

25. It is accepted practice that in preparing a lesson for a day, the setting of objectives is followed by the selection of _________ to achieve the objectives.a. activities and referencesb. methods and proceduresc. group leaders and membersd. strategies and techniques

26. To you, which of these skills is basic and necessary in all investigate activities of the learners?a. inferringb. comparingc. observingd. measuring

27. What is the reason why learning activities should be carefully planned?a. the accomplishment of the objectives depends on itb. the learners skill and attitudes are developedc. they are centered In the childrens energiesd. the teachers ability to plan is tested

28. Which of the following is manifested if there are available textbooks and materials for every learner?a. improvement of quality educationb. development of study skillsc. encouragement of the student to studyd. improvement of school and community relation

29. In your new class, you observed that pupils answer even when not called, about Maam to get your attention, and laugh whenever someone commits mistakes. What should you do to stop this malpractice?a. mistakes. What should you do to stop this malpractice?a. involve the whole class in setting rules to conduct for the classb. write the parents about their childrens misbehaviorc. send the pupils who are misbehaving to the guidance counselord. set the rules for the class to observe

30. During a typhoon, your room was one of those damaged and you were advised to hold classes on the stage. What should you do to manage the class?a. create the most conducive and comfortable setting out of the situationb. instruct other pupils not to loiterc. post a sign Class Going On so as not to disrupt classesd. arrange the pupils to the left side of the stage

31. What can you do to adapt yourself to the technological advances in teaching and learning?a. encourage my co- teachers to make use of themb. do away with the traditional methodsc. learn and apply the technologyd. be acquainted with the new technology

32. How does the Department of Education respond primarily to the changes occurring in the modern world?a. by simplifying administrative functionb. by establishing schools in every barangayc. by modifying the curriculumd. by giving more emphasis on teachers roles

33. Mr. XW provides his class with experience which is abstractions of the real world involving objects, processes or situations with goals, rules and rewards. Obviously, the ___________ approach is used by him.a. Discussionb. Role Playingc. Activityd. Simulation

34. Mr. Cruz is tired on his discussion method of teaching, so he tried a new one. The class invited resource persons and after their talks, the class was required to participate. This is called __________.a. Debateb. Symposiumc. Round table conferenced. Brainstorming

35. What method is used when a large number of imaginative ideas or solutions to open- ended problems are elicited from a group of individuals who are encouraged to expand their thinking beyond the routine sort of suggestions?a. Buzz sessionb. Brainstormingc. Fish bowl techniqued. Critiquing session

36. What method is resorted to by teachers to students who need more closely monitored practice and drills before they can proceed to other task? Corrective feedback is provided for them to grasp the materials and avoid frustrations?a. Programmedb. Independent Studyc. Remediald. Self- directed

37. Miss Santos grouped her class into small group of 3 to 4 members each. Each group was given time to discuss the problems. Reporters from each group presented the solutions to the given problems to the whole class. This technique is calleda. Buzz sessionb. Fish Bowl Techniquec. Forumd. Simulation

38. What method is used when a teacher provides various exercises with increasing difficulty to her class and the students are very receptive?a. story grammar, structuralb. diagnostic perspectivec. multi- leveld. dimensional

39. An experienced teacher of the school is requested to assist and help the inexperienced teachers. This strategy is called ____________a. peer teachingb. pair teachingc. peer coachingd. team teaching

40. Logically, both review and practice are necessary to reinforce retention of what has been learned. The latter is most useful in thea. changing of attitudesb. understanding of vague conceptsc. comparisons of concepts learnedd. mastery skills

41. You will be assigned to another school after the second grading period. You will:a. leave important completed school records to the principalb. report at once to the principal at the said schoolc. ask your co- teacher next to your room to complete your recordsd. ask the principal to complete all your records

42. A new co- teacher of yours comes terribly ill and could not teach her class. The principal is not in the school as he is attending a whole day meeting in another district. You willa. tell her to go home and dismiss her classb. combine her class to your classc. refer the matter to the teacher in charge of the school whenever the principal is outd. ask the assistant principal to teach her class

43. You were required eight hours to work although your official time is only six hours.a. leave the school when the principal is not watchingb. entertain the principal in her officec. gossip with your close friendsd. find something useful to do within the school building to complete the required eight hours

44. The barangay chairman needs you to lecture to the barrio youths but you have a class.a. tell him you cannot make itb. tell him to look after your class so that you can do what he is requestingc. bring your class to the Barrio Halld. refer matter to your principal for appropriate action

45. This is conflict of procedures to follow and responsibilities and functions as regards the issuance of records in your school. Which of the following will you suggest immediately?a. a workflow chartb. organizational chartc. action officed. grievance/complaint office

01. d02. d03. c04. c05. a06. d. A, B, C, and D07. a. A, B and D08. c09. c10. d11. b12. b13. a14. c15. d16. b17. a18. b19. c20. c21. b22. c23. b24. c25. d26. a27. b28. a29. d30. a31. c32. c33. a34. b35. b36. c37. a38. c39. d40. d41. a42. c43. d44. d45. d