NAT REVIEWER FOR GRADE 6

1. THIRD GRADING
• Describe characteristics of the earth’s interior layers
Read each questions. Choose the letter of the best answer.
Easy
1. Tina uses clay to construct a model of the Earth. Which layer of the model should be the
thickest?
A. Mantle
B. Outer core
C. Inner core
D. Crust
2. Which is the uppermost layer of the Earth?
A. Crust
B. Inner core
C. Mantle
D. Outer core
3. Which layer of the earth consists of liquid iron and nickel?
A. Crust
B. Inner core
C. Mantle
D. Outer core
4. The illustration shows the three main layers of the Earth. Which statement describes
Layer III?
A. It is the hottest layer of the earth
B. It is the largest layer of the earth
C. It is the outermost layer of the earth
D. It is the thinnest layer of the earth
5. Which statement describes the Earth’s mantle layer?
A. It is the Earth’s largest layer covering about 67% of its mass

2. B. It is the outermost and the thinnest layer of the Earth
C. It is the Earth’s innermost layer
D. It is made of iron and nickel
Average
6. The part of the earth that is solid but has the ability to flow is the
A. Lithosphere
B. Oceanic crust
C. Asthenosphere
D. Inner core
7. The crust of the earth is made mostly by
A. Oxygen and silicon
B. Iron and silicon
C. Iron and nickel
D. Copper and nickel
8. The layer that makes up most of the earth’s mass and volume is the
A. Mantle
B. Magma
C. Crust
D. Core
Difficult
9. The inner core is the hottest interior layer of the Earth. Why?
A. It is where heating of iron and nickel takes place so intensely
B. It is where the ring of fire is formed
C. It is composed of very hot tectonic plate
D. It is composed of hot gases
10. The Earth’s crust moves constantly although its movement is not felt by the people. Why
is the Earth’s crust in constant motion?
A. It is composed of big bodies of water like the oceans
B. It floats on a mantle of hot liquid rocks that move constantly
C. It is divided into smaller hot plates
D. It has a strong magnetic field

3. FIRST GRADING
• Identify major parts of the nervous system and their functions.
Easy
1. What are the main parts of the nervous system?
A. Brain, spinal cord and nerves
B. Hands, feet and tongue
C. Arteries, veins and capillaries
D. Heart, blood and blood vessels
2. The nervous system is the center of all mental activity including all the following except
________.
A. Thinking
B. Learning
C. Digesting
D. Memory
3. Which part of the nervous system is found throughout the body?
A. Neuron
B. Cerebrum
C. Vertebrum
D. Cerebellum
4. What is the biggest part of the brain?
A. Brain stem
B. Cerebrum
C. Cerebellum
D. Medulla Oblongata
5. Which organ of the human body serves as the control center of the nervous system?
A. heart
B. brain
C. kidney
D. skin organ

4. Average
6. Which parts of our nervous system transmit messages to the brain?
A. Bipolar cells
B. Receptor cells
C. Motor neurons
D. Sensory neurons
7. Which part of the brain controls reflex actions such as sneezing and eye blinking?
A. Cerebrum
B. Cerebellum
C. Temporal lobe
D. Medulla oblongata
8. Which is NOT a function of the spinal cord of the nervous system?
A. Pathway of sensory messages to the brain
B. Controls automatic response without passing the brain
C. Pathway of motor signals from the brain to the neurons to the glands or muscles.
D. Controls involuntary activities like breathing and digesting
Difficult
9. In what way does the nervous system function as a two – way communication system in
the body?
A. The brain receives messages through sensory nerves and sends out messages
through motor nerves
B. It has brain that consists of two hemispheres: the left and the right hemisphere
C. The spinal cord contains bodies of nerve cells where messages to the brain pass
through.
D. It has two vital organs: the brain and the spinal cord
10. You run to meet your mother in order to help her carry the basket full of groceries into
the house. In correct order, which parts of the neurons are involved in the relay of
messages in the given situation?
A. dendrites tissue axon
B. Nerve cell dendrites axon
C. Synapse axon dendrites
D. Dendrites axon synapse