Science 8
Chemistry and Biology
Year End Exam
I. IDENTIFY THE FAMOUS CONTRIBUTORS IN CHEMISTRY. WRITE THE
ANSWERS ONLY.
1. Water is the primal matter since water was found everywhere
2. All substances are composed of the four elements: air, earth, water and fire
3. All things are composed of tiny bits of matter that cannot be further divided
4. He proposed an atomic theory which developed a milestone in the history of
chemistry
5. An Irish physicist who proposed that electrical charge units are directly related
to the atoms. He called such units electrons
George Johnstone Stoney
Democritus
Humphry Davy
John Dalton
Robert Millikan
Aristotle
William Crookes
Thales
Eugen Goldstein
James Chadwick
I. IDENTIFY THE FAMOUS CONTRIBUTORS IN CHEMISTRY. WRITE THE
ANSWERS ONLY.
6. Conducted an experiment on the gas discharge tube or the cathode ray tube
7. An English chemist who discovered the existence of five elements: Ba,Ca,K,
and Sr
8. A German physicist who first discovered positive rays or streams of positive
ions
9. Conducted the first oil drop experiment
10. An English physicist who published his works identifying neutral particles that
exists in an atom
George Johnstone Stoney
Democritus
Humphry Davy
John Dalton
Robert Millikan
Aristotle
William Crookes
Thales
Eugen Goldstein
James Chadwick
II. TRUE OR FALSE
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Digestion is the process of converting food into forms that can be used by the
cells of the body.
The mouth or the oral cavity is the second part of the digestive system; it is the
place where food is digested.
The pharynx or throat is a passageway for both food and air.
The esophagus connects the pharynx to the stomach.
The stomach is an R-shaped, expandable bag in which most digestion occurs.
The stomach and the large intestine contain digestive juices and mucus that help
facilitate digestion.
The final digestion and absorption of nutrients takes place in the small intestine.
Enzymes from the accessory digestive glands help hasten chemical reactions.
Fibrous foods help clean the small intestine and facilitate comfortable
elimination of undigested food.
The appendix is the small sac located in the lower right side of the abdomen.
III. WRITE THE LETTER OF THE CORRECT ANSWER
1. The fluid that helps emulsify fat
a. Appendix
2. The first segment of the small intestine
b. Bile
3. The longest organ in the digestive tract
c. Duodenum
4. The common passageway for food and air
d. Jejunum
5. The enzymes that aid in the digestion of fats
e. Large intestine
6. The valve that prevents the backflow of food
f. Lipase
7. The organ that can act as temporary storage of food
g. Pharynx
8. The folds that increase the absorption area of the stomach
h. Small intestine
9. The small sac located on the lower right side of the abdomen i. Sphincter
10. The organ responsible for the final absorption of water and j. Stomach
salt
k. Rugae
III. WRITE THE LETTER OF THE CORRECT ANSWER
11. The conservation method done in the natural habitat
12. The conservation method outside of the natural habitat
13. Producers in the ecosystem
14. They depend on other organisms for food.
15. It refers to the sequence of food transfer
from one trophic level
16. An interlocking pattern of food chains.
17. A model which represents the number of
organisms at each trophic level
18. The process where liquid becomes gas
19. The conversion of nitrogen gas to nitrate
20. The conversion of nitrate to nitrous oxide
A. denetrification
B. nitrification
C. in-situ conservation
D. Ex-situ conservation
E. evaporation to the next.
F. pyramid of numbers
G. Autotrophs
H. Heterotrophs
I. food web
J. food chain