Animals need other organisms to survive and plants only need sunlight and water
Answer:
Oxygen levels stay above 15 percent starting 200 million years ago
Explanation:
Atmospheric oxygen levels are related to the evolution on Earth and changes in geochemical cycles that involve climate variations.
The presence of O
2 and evolution of oxygen gave new opportunities to the life on Earth. Oxygen levels in atmosphere have fluctuated between 15% and 35% of atmospheric volume, since the start of the Cambrian period.
So, form the starting 200 million years ago, oxygen level stay above 15 percent and the correct option is "B".
Specific gravity<span>reflects the amount of wastes, minerals, and solids present in the urine</span>
Answer:
LIGHT ENERGY is converted to CHEMICAL ENERGY in the process of PHOTOSYNTHESIS
Explanation:
According to the law of conservation of energy, energy cannot be created nor destroyed but can only be changed from one form to another. This means that no form of energy gets destroyed but only transformed. This is evidently so in so many natural processes including the process of PHOTOSYNTHESIS undergone by plants.
Photosynthesis, which is the way plants obtain their food via sunlight, converts the LIGHT ENERGY of the sun to CHEMICAL ENERGY in glucose produced. Hence, photosynthesis obeys the law of conservation of energy.
Answer:
Please find the detailed explanation/description on how to use the light microscope to view a wet mount of a protist. The 9 structures mentioned in the question are in CAPS.
Explanation:
- Firstly, the slide containing the wet mount of the protist is prepared and placed at the centre of a lowered STAGE. The STAGE CLIPS over the sides of the slide are used to hold it in place.
- The revolving turret or nosepiece is turned so that the LOWEST POWER OBJECTIVE LENS is in position i.e. directly above the sample/slide. The SCANNING OBJECTIVE LENS, the lowest objective lens with power of 4x is used initially.
- The slide is viewed through the EYEPIECE, and the image is brought into focus using the STAGE KNOBS.
- The COARSE FOCUS KNOB is turned until the protist on the slide is brought into broad focus. The FINE FOCUS KNOB is then used to bring the image on the slide into sharp focus.
N.B: The OBJECTIVE LENS should not touch the cover slip on the slide during this process.
- When the protist on the slide is clear using lowest power objective lens, the revolver turret can be rotated to allow HIGHER POWER OBJECTIVE LENS.
- Due to higher magnification of the HIGH POWER OBJECTIVE LENS, the protist might need to be refocused using the FOCUS KNOBS.
