Answer:
According to the current fossil record, scientists believe that the life on earth began about 3.5 billion years ago.
I think the answer is non reactive. As the outer shells gets filled ,valency decreases, so reactivity also decreases.
All the best
Answer:
Consuming tuna from a dented, bulging can. (Ans. C)
Explanation:
Botulism is a rare poison, and caused by a toxin which is known as clostridium botulinum. Botulinum requires emergency medical care because sometimes it can be fatal. It can spread through contaminated water, food, and by touching the surface area which is contaminated.
Symptoms of botulism includes:
1) Difficulties in speaking, and facial weakness.
2) Pain in the abdomen area.
3) Weak eye muscles.
4) Feeling dizziness.
5) Double vision or blurred vision.
Answer:
Option). Centriole.
Explanation:
Centrioles are small, cylindrical cell organelles, present near the nuclei of animal cells. They are involved in formation of spindle fibers at the time of cell division that help in proper separation of chromosomes during cell division. Plant cells do not have centrioles.
Nucleus and ribosomes are present in both animal and plant cells, while cell wall is found only in plant cell. Thus, the organelle in diagram that should be listed under 'animal only' will be 'centriole.'
