Answer:
Ozone (O₃) gas
Explanation:
In the Earth's stratosphere, oxygen gas (O₂) is combined with atomic oxygen (O) to form ozone gas (O₃). This is very important because ozone protects the life on Earth from ultraviolet (UV) radiation from the Sun. UV radiation is high-energy radiation, and it is very dangerous for living organisms. Ozone molecule (O₃) absorbs UV radiation and it breaks down by forming O₂ and atomic oxygen (O) again. In this way, it protects the Earth from nocive radiation.
Answer:
D) A and C
Explanation:
Gram staining is a laboratory technique used for bacterial species. It is used to differentiate between two groups of bacteria based on the components of their cell wall. Gram staining was developed by a scientist called Christian Gram in the year 1884. In the gram stain procedure, the following occurs:
- Due to the thick peptidoglycan component of their cell wall, GRAM POSITIVE bacteria retains the crystal violet due and stain VIOLET.
- On the contrary, due to the thin peptidoglycan component of their cell wall, GRAM NEGATIVE bacteria do not retain the crystal violet dye and hence stain, RED.
Based on this, a bacteria that has been gram stained has been tested for its GRAM REACTION and microscopic morphological characteristics, since it is a microbe.
Dehydration because animals can only live so long with water
True they can be man made and naturally made.
Answer:
Explanation:
Escherichia coli, is a type of bacteria that lives in the intestines. It's also found in the gut of some animals. Most of them are harmless, they aid keeping the digestive tract healthy. Though if contaminated food or fouled water is consumed, some strains can cause diarrhea .
Catalase enzymes, hydroperoxidase I (HPI) and HPII, catalyze the dismutation of hydrogen peroxide to water and oxygen but they play crucial roles in protecting cells against the effects of oxidative stress.
Some examples of pathogenic microorganisms which produces catalase include staph, bacillus, aureus,etc
Test Procedure:
- With the aid of a loop or sterile wooden stick, a small amount of bacterial colony should transferred onto the surface of clean, dry glass slide .
- A drop of 3% Hydrogen peroxide should be placed on to the slide and mixed.
- A positive result is indicated by the rapid evolution of oxygen gas (within 5-10 seconds), which is evident by bubbling, while a negative produces no bubbles or only a few scattered bubbles.
- The used slide should be disposed in the bio hazard glass disposal container.