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SCIENCE VI NAT REVIEWER

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Page 1: Science vi nat reviewer

SCIENCE VINAT REVIEWER

Page 2: Science vi nat reviewer

THE MALE AND FEMALE REPRODUCTIVE

ORGANS AND THEIR FUNCTIONS

Page 3: Science vi nat reviewer

THE FEMALE REPRODUCTIVE SYSTEM

The female reproductive anatomy includes internal and external structures.

The function of the external female reproductive structures (the genital) is to enable sperm to enter the body and to protect the internal genital organs from infectious organisms.

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THE MAIN EXTERNAL STRUCTURES OF THE FEMALE REPRODUCTIVE SYSTEM INCLUDE:

1. Labia majora: The labia majora enclose and protect the other external reproductive organs. The labia majora contain sweat and oil-secreting glands. After puberty, the labia majora are covered with hair.

2. Labia minora: They lie just inside the labia majora, and surround the openings to the vagina and urethra.

3. Bartholin's glands: These glands are located next to the vaginal opening and produce a fluid (mucus) secretion.

4. Clitoris: The two labia minora meet at the clitoris, a small, sensitive protrusion that is comparable to the penis in males. The clitoris is covered by a fold of skin, called the prepuce, which is similar to the foreskin at the end of the penis. Like the penis, the clitoris is very sensitive to stimulation and can become erect.

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THE INTERNAL FEMALE REPRODUCTIVE SYSTEM :

1. Vagina: The vagina is a canal that joins the cervix (the lower part of uterus) to the outside of the body. It also is known as the birth canal.

2. Uterus (womb): The uterus is a hollow, pear-shaped organ that is the home to a developing fetus. The uterus is divided into two parts: the cervix, which is lower part that opens into the vagina, and the main body of the uterus, called the corpus. The corpus can easily expand to hold a developing baby. A channel through the cervix allows sperm to enter and menstrual blood to exit.

3. Ovaries: The ovaries are small, oval-shaped glands that are located on either side of the uterus. The ovaries produce ova and hormones.

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THE INTERNAL FEMALE REPRODUCTIVE SYSTEM :

1. Fallopian tubes: These are narrow tubes that are attached to the upper part of the uterus and serve as tunnels for the ova (egg cells) to travel from the ovaries to the uterus.

2. Cervix: The cervix is the lower end of the uterus. It is located at the top of the vagina and is about one inch long. The cervical canal passes through the cervix, allowing blood from a menstrual period and a baby (fetus) to pass from the womb(uterus) into the vagina. The cervical canal also allows sperm to pass from the vagina into the uterus.

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THE MALE REPRODUCTIVE SYSTEM

The penis and the scrotum are the external organs. The penis is the organ for reproduction andfor urination. Behind the penis is the scrotum, a sac-like pouch that supports the testes. The testes begin to produce sperms during puberty.

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THE MALE REPRODUCTIVE SYSTEM Each testis produces billions of sperm cells. Each sperm, the male reproductive cell, has a head and a tail. The

tail makes the sperms move very fast. The sperm travels from the testes through the tubes called the

vas deferens that circle the bladder. The bladder is a sac that serves as the receptacle for urine. Behind the bladder is the gland called seminal vesicle. This gland

provides the sperms with a fluid that enables them to move. The mixture of the sperm and the fluid is known as the semen. The

semen leaves the body via the urethra. Urethra is also the tube that carries urine out from the body. A

muscle at the back of the bladder contracts during ejaculation to prevent urine from entering the urethra.

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TEST YOURSELF.

1. What is another name for the uterus? a. stomach b. womb c. ovary d. marrow

2. What is the name of the tube that carries the egg cell to the uterus? a. fallopian b. urethra c. aorta d. Vagina 

3. What do the ovaries store?a. Semen b. embryos c. sperm d. egg cells

4. The cervix is the connection between which two structures? a. penis and testicles b. fallopian tube and ovaryc. vagina and uterus d. elbow and wrist

5. Only girls have a urethra. a. True b. False c. Definitely d. Maybe

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TEST YOURSELF.

6. Name the parts labeled A and B in the diagram.

a. A=prostate gland B=urethrab. A=scrotum B=prostate glandc. A=scrotum B=urethrad. A=sperm duct B=penis

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TEST YOURSELF.

7. The diagram shows a sperm. The tail enables the sperm to swim. Why does the sperm need to be able to swim?

a. In order to get the eggb. Because it is a member of the fish familyc. So that it does not drown in the semend. To travel around in the testicle

8. Which of the following is not part of the male reproductive system?

e. seminal vesiclesf. urethrag. prostate glandh. kidney

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TEST YOURSELF.

9. The tube that connects to the bladder and carries urine out of the body is called the___________?

a. artery b. fallopian c. penis d. Urethra

10. Which of the following surrounds the testicles?

a. The sperm duct b. The scrotum c. The urethra d. The penis

 11. Another name for the sex cell is ___________.

a. hormone b. gamete c. zygote d. testicle

 12. A gamete is the name given to the sex cell produced by either parent. What is the name of the male gamete?

a. Egg b. Sperm c. Semen d. hormone

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TEST YOURSELF.

12. Name the part labeled X in the diagram that produces fluids which help the sperm to swim?

a. Ureter b. Prostate glandc. Urethra d. Scrotum

13. Where is the hormone testosterone made? a. penis b. uterus c. testicles d. kidney

14. Identify the parts labeled A and B in the diagram of a sperm shown.

b. A=nucleus B=legc. A=head B=nucleusd. A=nucleus B=taile. A=head B=tail

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HOW THE RESPIRATORY SYSTEM WORKS

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15. What is the purpose of the little hairs inside the nose?a. To fight disease. b. They serve no purpose.c. To keep dust out of the lungs. d. To tickle the nose and cause sneezes.

16. What is another name for the windpipe?

a. Lungs b. Larynx c. esophagus d. Trachea

18. Air can enter the body and travel to the lungs _____________________.

a. through the mouth b. through the esophagus and gullet

c. through the windpipe and the pores d. thru the nose and the nervous system

19. What is the respiratory system?

a. The body’s breathing system. b. The body’s system of nerves.

c. The body’s food processing system. d. The body’s blood transferring system.

20. What happens to the windpipe, or trachea, before it reaches the lungs?

a. It branches in two directions b. It branches in three directions.

c. It vibrates and creates sounds. d. It closes up so that no oxygen can escape.

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21. What important activity takes place in the lungs?a. Food is digested. b. Liquid waste is filtered from the blood.c. Oxygen is exchanged for carbon dioxide. d. The trachea is exchanged for the larynx.

 22. Oxygen moves from the lungs into the bloodstream through _______________.

a. nerve fibers b. a large artery in the heart

c. small blood vessels in the lungs d. a tube in the lungs called the jugular vein

 23. When we breathe in, we inhale many gases, including oxygen. What happens to the gases that the body can't use?

a. They are exhaled. b. They are changed into oxygen by the lungs.

c. They circulate through the body and are disposed of later.

d. They are absorbed into the digestive system and used to create energy.

24. What are lungs for?

a. To digest food. B. To help us breath.

c. To help us be active. D. To help us excrete waste

25. What body structure protects the lungs from outside harm?a. Cartilage b. Tiny sacs c. The rib cage d. The diaphragm

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26. To go on living, the body's cells need food, water, chemicals, and _____________.

a. helium b. oxygen c. vegetables d. carbon dioxide

27. What happens when you breathe in?

a. your diaphragm expands and your ribcage contracts

b. your diaphragm contracts and your ribcage expands

c. your diaphragm explodes and your ribcage contradicts

d. All of the above

28. What are bronchial tubes?

a. air passages inside your lungs b. blood vessels inside your body

c. tiny air sacs that deliver oxygen to the blood d. none of the above

29. Air enters your lungs through the __________.

a. trachea b. esophagus c. alveoli d. bronchial tubes

30. What systems are working together during the process of respiration?

a. Respiratory and lymphatic system. B. Respiratory and cardiovascular system.

c. Lymphatic and cardiovascular system. D. Respiratory, lymphatic & cardiovascular system.

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URINARY SYSTEM AND ITS FUNCTIONS

The urinary system removes substances from the blood in the form of urine and regulates various metabolic processes. The urinary system is made up of two kidneys, two ureters, the urinary bladder, two sphincters and the urethra.

 Two kidneys - a pair of purplish-brown organs located below the ribs toward the middle of the back. Their function is to remove liquid waste from the blood in the form of urine; keep a stable balance of salts and other substances in the blood; and produce erythropoietin, a hormone that aids the formation of red blood cells.

The kidneys remove urea from the blood through tiny filtering units called nephrons. Each nephron consists of a ball formed of small blood capillaries, called a glomerulus, and a small tube called a renal tubule. Urea, together with water and other waste substances, forms the urine as it passes through the nephrons and down the renal tubules of the kidney.

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URINARY SYSTEM AND ITS FUNCTIONS

 Two ureters - narrow tubes that carry urine from the kidneys to the bladder. Muscles in the ureter walls continually tighten and relax forcing urine downward, away from the kidneys. If urine backs up, or is allowed to stand still, a kidney infection can develop. About every 10 to 15 seconds, small amounts of urine are emptied into the bladder from the ureters

Bladder - a triangle-shaped, hollow organ located in the lower abdomen. It is held in place by ligaments that are attached to other organs and the pelvic bones. The bladder's walls relax and expand to store urine, and contract and flatten to empty urine through the urethra. The typical healthy adult bladder can store up to two cups of urine for two to five hours.

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URINARY SYSTEM AND ITS FUNCTIONS

• Two sphincter muscles - circular muscles that help keep urine from leaking by closing tightly like a rubber band around the opening of the bladder.

• Nerves in the bladder - alert a person when it is time to urinate, or empty the bladder.

• Urethra - the tube that allows urine to pass outside the body. The brain signals the bladder muscles to tighten, which squeezes urine out of the bladder. At the same time, the brain signals the sphincter muscles to relax to let urine exit the bladder through the urethra. When all the signals occur in the correct order, normal urination occurs.

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31. The urinary system includes all but which of the following?

a. Urethra b. ureters c. kidneys d. adrenal glands 

32. What are you doing when your diaphragm and rib muscles contract and air enters the space created inside your chest cavity?

a. Coughing b. Eating c. Inhaling d. Exhaling

 33.   Functions of the urinary system include all of the following except:  a. Regulating blood volume.b. Conserving nutrients by preventing their excretion in the urine.c. Regulating plasma concentrations of ions by controlling the amount lost in

the urine.d. Regulating blood pressure.

 34. What is the purpose of the little hair inside the nose?

a. To fight disease. B. They serve no purpose.

c. To keep dust out of the lungs. d. To tickle the nose and cause sneezes.

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35. Structurally, a kidney is__________________.  a. approximately the size of a full gall bladder.b. soft enough to change shape dramatically in response to the activity of

abdominal organs that might constrict it. c. covered by four capsular layers.d. kidney-bean shaped.

36. A glomerulus___________________________.e. is a portion of the proximal convoluted tubule.f. occurs in the Loop of Henle.g. filters urine just prior to its exit from the kidney. h. is a capillary knot contained within the renal corpuscle.

37. Which of the following is not true of nephrons?   i. There are roughly 2.5 million nephrons in each kidney.j. Each nephron consists of a long renal tubule.k. They can be viewed only with a microscope.l. One type occurs only in the medulla of the kidney.

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38.   A nephron has two parts, and these are the______________. a. glomerulus and collecting duct.b. renal corpuscle and renal tubules.c. collecting duct and convoluted tubules.d. proximal convoluted tubule and distal convoluted tubules

39. The renal medulla is composed of tissue called ______. a. renal pyramids b. nephrons c. renal sinus d. renal pelvis

40. Which is found in the highest concentration in the urine? a. Uric acid b. Urea c. Glucose d. Creatinine

41. The ___________________ is the functional unit of the kidney.

a. renal pyramid b. renal medulla c. nephron d. renal cortex 

42. Where is the location of the external urethral sphincter in the human male?

a. prostatic urethra b. spongy urethra

c. membranous urethra d. tip of the penis

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4c. An infection of the urinary bladder is termed _________________.

a. Urethritis b. cystitis c. nephritis d. glomerulonephritis

  4d. How is excess salts and minerals from the bladder remove?

a. by respiration b. by the sweat glands

c. by digestion d. by urination

  45. Which organ excretes urine?

a. Kidneys b. sweat glands c. large intestine d. anus

 

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CLASSIFICATION OF VERTEBRATES

Vertebrates possess a skull that protects the brain. Vertebrate skulls house the sensory organs for taste, smell, hearing and vision. Most vertebrates have two pairs of appendages which can take the form of wings, flippers, fins, arms or legs.

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CLASSIFICATION OF VERTEBRATES

1. Amphibians - live both on land and in the water. They are cold- blooded animals with three- chambered heart.

2. Mammals - generally considered the most advanced members of the animal kingdom.

3. Reptiles - they have either an outer covering of scales or thick, leathery plates.

4. Birds - they are warm-blooded, they consume a great deal of food to maintain their body temperature.

5. Fishes - are vertebrates with special characteristics that allow them to spend all or part of their lives in water.

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46. What do you call animals that are cold-blooded with three-chambered heart as well as other organs are commonly found?

a. Birds b. Mammals c. Amphibians d. Fish47. What are the typical examples of amphibians?

a. Frogs, toads and salamanders b. Giraffe, cat and dogsc. Sharks, salmon and trout d. Turtles, reptiles and lizards

48. How do amphibians protect themselves?a. by quickly scurrying away from dangerb. absorb oxygen into their bodies through their skinc. they need parental care to protect them.d. by hiding into the grasses.

49. The picture below shows several different birds.

What characteristic do all birds share?

a. They can fly.

b. They have feathers.

c. They have webbed feet.

d. They eat worms.

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50. Which of the following questions is testable in a scientific investigation? a. Are dogs better pets than cats?b. b. Are dogs happy when they are walked?c. Are cats more active at night than during the day? d. Are cats easier to take care of than dogs?

 51. What are the special characteristic of a fish and amphibians?e.  Allow them to spend all of part their lives in water.f. They are oviparous and lay eggs with brittle shells which must be incubated while

they develop.g. They breathe exclusively through the use of well-developed lungs.h. They possess hair that can cover all or part of their bodies.

52. Which of the following mammals belong to phylum Chordata?a. giraffe b. dog c. elephant d. frog

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53. The following are characteristics of mammals, which one does not belong to the group?

a. They are members of Phylum Chordata.b. They are the most advanced members of the animal kingdom.c. They are nourished with milk secreted by the mammary glands of their mothers.d. They are more sophisticated than other types of animals.

 54. What are the two classes of fish?

a. Chondrichthyes and osteichtyhyes b. Aves and reptilia

c. Chordata and mammalia d. All of the above

55. What are the common characteristics of a bird?

a. They are warm blooded.

b. They consume s great deal to maintain their body temperature

c. Have highly efficient respiratory system and a fast beating.

d. All of the above

 56. Which group of animals has bones?

a. Vertebrates b. Invertebrates c. Subphylum Vertebrata d. Chordata

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CHARACTERISTICS THAT ENABLE ANIMALS TO SURVIVE IN AN ENVIRONMENT.

Animals characteristics include numerous adaptations that enable them to survive in a wide range of environments. They live in nearly every habitat around the globe, from frigid polar regions, to turbulent seas, to dense tropical forests. Animals also possess body structures that help them get their food. They also possess body structures to protect themselves .

Modern mammals range in stature from tiny field mice to massive whales and although various species may look drastically different, all mammals still share a unifying set of characteristics. Some mammal characteristics—such as their hair, mammary glands, and three specialized middle-ear bones—are shared by no other groups of animals.

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CHARACTERISTICS THAT ENABLE ANIMALS TO SURVIVE IN AN ENVIRONMENT.

Fish are found nearly everywhere there is water with enough food, oxygen and cover. Near your home there should be a body of water that has fish living in it.

Amphibians have adapted to survive in many different types of habitats. They can be found in forests, woodlots, meadows, springs, streams, rivers, lakes, ponds, bogs, marshes, swamps, vernal ponds and even farmland.

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CHARACTERISTICS THAT ENABLE ANIMALS TO SURVIVE IN AN ENVIRONMENT.

ANIMAL ADAPTATION

1. MIMICRY – Imitating the shapes, colors, smells or sounds of other animals.

2.  MIGRATION – Movement of animals to warmer places during winter. Movement from one place to another during certain seasons of the year.

3.  CAMOUFLAGE – Copying the features of a superior animal to protect oneself from its enemies.

4.  GROUP LIFE – Animals gathering together usually following a leader.

5.  ESTIVATION – Deep sleep during summer that lasts for a long time.

6.  HIBERNATION – Deep sleep during winter that last for a long time.

7.  PROTECTIVE COLORATION – Blending of an animal’s color to its surrounding.

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58. Which of the following animals live in the pond?

  a. rabbit b. milkfish c. dove d. cat

 59. Koala bears live on ___________.

a. fruit bearing tree b. mountain c. eucalyptus Three d. acacia tree

60. What kind of poison does Puffer fish have?

a. Venom b. Tetradon Toxin c. Cyanide d. ethanol

61. Mosquitoes breed and stay in _____________________.

a. clear stagnant water b. trees and bushes

c. rice field with plenty of grains d. inside the house

62. Most animals sleep during winter, what do we call this?

a. Camouflage b. Hibernation c. Estivation d. Rainy season

63. Largest bird in existence, this bird cannot fly although it has a pair of wings.

a. Kiwi b. Ostrich c. Vulture d. Dove

 

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64. Animals that can blend with its surrounding are called ___________.

a. camouflage b. blending c. coloring d. eagle

 65. Which of these animals demonstrates cryptic coloration?

a. native ducks b. bumble bee c. grasshopper d. tamaraw

 66. Which of these describes cryptic coloration?

a. blends with the environment b. changes the environment

c. changes in color d. invisibleness

• 67. Some animals like fish can live only in water. Some animals can live only in land. Why can animals live in a particular environment?

a. They live where they can get food.b. They live where the temperature is hotc. They live where they have no enemies.d. They live where the temperature is cold.

68. Where would you most likely find a bird with long, stilt-like legs, pointed beak?

a. River b. Garden c. Forest d. Desert

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69. Why do polar bears have thick furs?a. So that they can walk fast. B. So they can sleep better.c. So that they are good to look at. C. So that they can always feel warm.

 70. Which of the following animal characteristics in NOT mimicry?a. Frogs change their colors.b. Turtles hide under their hard shellsc. Walking sticks blends with twigs and under bush.d. Sphinx moth resembles its wooden resting place.

 71. Animals live in places where they can find food and shelter. Which animal is mostly likely in frigid climates?

a. Camel b. Polar Bear c. Lion d. Monkey

72. Why do many desert animals eat meat?c. Desert animals do not like plants.d. Desert animals cannot chew grass.e. Desert animals always hide under the ground.f. There are more meats than plants in the desert.

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73. How do animals in cold places adapt to his cold surroundings?a. They have thick skin to keep their body warm.b. Their body’s color blends with their surroundings.c. They have layers of fats to keep their body warm.d. They have feathers or hair to keep their body warm.

 

7d. How does a skunk protect itself from its enemies?e. It blends its color with the environment.f. It mimics the sound and shape of its prey.g. It secretes a foul-smelling substance that keeps its enemies away.h. They play dead.

 75. How do ants, monkeys and elephants protect themselves from their enemies?

i. They group themselves.j. They develop strong legs for running.k. They produce loud cries to scare away their enemies.l. They change color that blends with the surroundings.

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• 76. How do bears prepare themselves for hibernation?

a. They grow large thick furs.

b. They build nests for themselves.

c. They change the color of their furs.

d. They eat enormous amount of food just before winter.

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DESCRIBE THE CHARACTERISTICS OF DIFFERENT KINDS OF PLANTS.

• Plants have special characteristics which help them adapt to their environment.

•  

1. PROTOPHILIC – Plants that adapt to intense light.

2. PHOTOPHOBIC – Plants that grow in shady areas

3. PARASITE PLANTS – Non-green plants survived by getting food from other living things.

4. SAPROPYTES – plants line on the body of once living thing.

5. HYDROPYTES – Plants with special structures that allow the passage and storage of air within their tissues.

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77. The branches and stems of plants move towards source of light. This type of movement is called _____.

a. geotropism b. hydrotropism c. chemotropism d. phototropism

 78. Seeds are dispersed from one place to another. Which seed is best suited for dispersal by means of animals like birds?

a. Narra b. Guava c. Coconut d. Mango

79. How do colors of flowers help the plant in reproduction?

a. They help in beatifying the garden.

b. they drive insects that harm the plants.

c. They attract insects that help in reproduction of plants.

d. To attract insects that protects plants from harmful enemies.

80. Why do coconut seeds and fruits easily float on water?a. They have light husks.b. They have seeds in cones.c. They have smooth coverings.d. They have feathery structures.

 

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81. What characteristics make the water hyacinth float in water?

a. Light weight of the plants. B. Light, rounded, waxy leaves.

c. Bulbous stems filled with air. D. Spreading, feathery root stem.

82. Why mosses able to live on damp rocks?a. Because they can make rock slippery.b. Because they can cut down water loss.c. Because they can give off carbon dioxide.d. Because they can absorb water better in this place.

83. What makes rain and snow easily slide of pine trees?

I. Its waxy-coated leaves.

II. Its needle-shaped leaves.

III. Its drooping leaves and branches.

 a. I and II only b. I and III only c. II and III only d. I, II and III

 84. Which plants have leaf surfaces covered with hairs?

a. Mango b. Squash c. Tomatoes d. Calamansi

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85. Some people plant bougainvillea along fences to prevent people from passing through. What prevents people from touching or getting near bougainvillea plant?

a. It has hooks.b. It has sticky juice.c. It has sharp thorns.d. It has unpleasant smell.

 

86. How do some mushrooms protect themselves from animals?e. By growing spines.f. By having fine hairs.g. By producing poison.h. By emitting bad smell

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DIFFERENTIATE PHYSICAL FROM CHEMICAL CHANGES/PROCESSES

1. PHYSICAL CHANGE – Involves the change in phase, size, and shape of matter but not changing its chemical properties. It does not produce new substances. The new form may be changed back in to the old form.

Tearing cutting crumpling

Drying pounding breaking

Molding bending shaping

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DIFFERENTIATE PHYSICAL FROM CHEMICAL CHANGES/PROCESSES

2. CHEMICAL CHANGE – It alters the chemical characteristics of matter, thus forming a new substance. It cannot return to its former structure.

Some evidences of chemical changes are:formation of gasformation of precipitatechange in colorproduction of light and heat energyburning, cooking, rusting, decaying, fermenting.

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87. Michelle hung wet clothes outsides the house during a sunny day. After hours they all dried up. What change took place?

a. Physical change b. Chemical change

c. Physical and chemical change. D. None of the above.

 88. Hazel heated the sugar to make syrup. What change was brought by heating?

  a. Physical change b. Chemical change

c. Physical and chemical change d. No change at all

 89. Your mother brought ½ Kilo raw mangoes from the market. She placed them in a basket. After 3 days, the green mangoes turned yellowish in color. What changes took place?

  a. Physical change b. Chemical change

c. Energy change d. Electrical change

 90.A child pours water into a plastic container in the freezers. After an hour it turned ice. What change took place?

  a. Physical change b. Chemical change

c. Energy change d. Electrical change

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91. How can you produce a chemical change in wood?

  a. Chop it b. Cut it into many tiny places c. Burn it d. Put it in water

For Items Number 92 and 93, refer to the box listing the different changes take place.

9b. Which are examples of chemical change?a. A, B, Cb. A, B, Fc. B, D, Fd. C, D, E

9c. Which are examples of physical change?e. A, B, Cf. A, B, Fg. C, D, Eh. D, E, F

A. Ripening of fruits D Evaporating saltwaterB. Burning of wood E. Sewing cloth into a dressC. Cementing processes F. Coconut water turning into vinegar

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For item 94, refer to the box below.

9d. Which statement is true about the changes in the two given examples?a. I is physical change. II is chemical change.b. I is chemical change. II is physical change. c. I and II are physical changes.d. I and II are chemical changes.

95. Which of the following is a result of a chemical change?e. Frozen water f. Broken glass g. Chopped woodh. Tarnished silverware

96.Which of the following is a result of physical change?i. An iron nail becomes rusty.j. Burning a piece of paper.k. Nail polish was removed from the fingernails using acetone.l. Mixing of salt and water.

I – melting iceII – melting wax 

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OXYGEN –CARBON DIOXIDE CYCLE

•  

• An ecosystem has materials that plants and animals used in order to live. Among these materials are oxygen and carbon-dioxide.

• Oxygen is a gas released as a by-product of photosynthesis. It is cycled in the environment.

• Carbon dioxide is released in respiration .It is also released when decomposition occurs.

• Oxygen is released by plant sand is taken in by animals for respiration while carbon dioxide is taken in by plants for photosynthesis.

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97. In the carbon-oxygen cycle carbon gas and oxygen gas mixes in the ____________.

a, atmosphere b. soil c. fossil fuel d. factories

98. Carbon dioxide is taken in by plants through the process called_______________.

a. symbiosis b. photosynthesis c. chemical process d. All of the above

 99. Carbon gas can be stored underneath the earth as a _____________.

a. fossil fuel b. soil c. water d. garbage

 

100. Carbon- dioxide is one of the gases that cause the warming of the atmosphere. This condition is known as the ____________.

a. global warming b. green house effect c. thermal energy d. heat

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101 .The cycle shown in the illustration below is ____________.

a. carbon cycle b. carbon –oxygen cycle

c. oxygen cycle d. none of these

 102. Which statement is true about the plants in the illustration?a. They give off carbon-dioxide for animals use.b. They give off oxygen for children use in breathingc. They need oxygen to synthesize glucose and photosynthesisd. They need carbon-dioxide from the sun to manufacture food.

103. Which statement is true about the animals in the illustration?e.  They give-off carbon-dioxide for plants usef. They need carbon-dioxide from the plants for breathingg. They give off oxygen gas for plants use in photosynthesis.h. They need the sun which provide them oxygen for breathing

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The plants and the fish in the aquarium show a basic type of ecosystem.

104. Which statements above illustrate the dependence of one organism to another?a. The fish can make food through the help of the plantsb. The fish needs the plants for reproduction and the plants need the fish for

protection.c. The fish need carbon-dioxide from the plants for respiration and the plants

oxygen from the fish for photosynthesis.d. All of the above.105. What will if the supply of carbon –dioxide is permanently cut off? a. Green plants will grow b. Photosynthesis cannot take place c. Animals can not undergo respiration d. All of the above106. What is a by-product of respiration?a. Oxygen b. Carbon –dioxide and water c. Nitrogen d. Both 1 & 2

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ENCIRCLE THE NUMBER OF THE CORRECT ANSWER.

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