The dark colored organic matter formed in the soil by the decomposition of animals and plants, is referred as:
A. Fossils
B. Humus
C. Chalk
D. Slit
Bacteria help to break dead:
A. Ends
B. Organic matter
C. Fossils
D. Alloys
Explanation: Bacteria play a crucial role in the decomposition process by breaking down dead organic materials such as plants, animals, and other biological substances, aiding in nutrient recycling and returning essential elements to the ecosystem.
Which of the following tools is more efficient for the production of electricity from the sun?
A. Galvanic cell
B. Solar cell
C. Lead cell
D. Dry cell
Repeated sessions of contraction and relaxation, are mainly associated with:
A. Supporting tissues
B. Nerve tissues
C. Muscle tissues
D. Epithelial tissues
Explanation: Muscle tissues are specialized tissues in the body that are responsible for contraction and relaxation, allowing for movement and other bodily functions. Skeletal muscles, smooth muscles, and cardiac muscles are all examples of muscle tissues that undergo repeated cycles of contraction and relaxation.
Which of the following elements are called transition elements?
A. group A
B. Group B
C. both a and b
D. none of these
Explanation: Group B metals are referred to as transition metals. They are located in the middle of the periodic table between Group IIA and Group IIIA.
Light sensory cells which are linked to optical nerve, from _____.
A. Retina
B. Yellow spot
C. Blind spot
D. sclerotic
