The answer is option A.
The Student identifies the test tube
that stops bubbling first contains the catalyst.
Because Catalyst is a substance which
increases the rate of reaction, and the reaction shows that when a product is
obtained bubbles formed.
<span>When the student added X, Y and Z to the
test tubes. The one which is a catalyst fastened the reaction.</span>
Answer:
C.
Explanation:
The axial skeleton include the vertebrae, sacrum, coccyx, ribs, and sternum. The main focus of these is to protect the vital organs. The appendicular skeleton is made up of pectoral and pelvic girdle along with forearms, hands, feet, ankle. The main purpose, movement.
Answer:
skeletal muscles control his leg movement and cardiac muscles control his heart rate
<span>Anton van Leeuwenhoek learned to grind lenses ( 1668) and develop simple microscopes.
</span>
Leeuwenhoek heated the middle of a small soda glass rod , over a flame. On pulling apart the two ends, the glass rod elongated into thin whiskers .
Heating the end of this whisker resulted in a tiny high quality glass sphere. These glass spheres then became the lens of his microscope, with the smallest sphere providing the greatest magnification.
Leeuwenhoek's designs were very basic. The body of the microscope was a single lens mounted in a tiny hole on a brass plate. The specimen was then mounted on a sharp point that sticks up in front of the lens. It's position and focus could be adjusted by turning the two screws.
The entire instrument was about 3 to 4 inches long and had to be held up close to the eye, requiring good lighting and great patience to use.
