Answer:
four
Explanation:
Carbon atoms have four electrons in their outer shell. So, it exhibits tetravalency & thus, a single carbon atom can form a maximum of four (4) bonds with other atoms
Answer:
Our immune system produces antibodies against that antigen of pathogen.
Explanation:
Injecting an antigen from a pathogen would help our immune system memorize the infection and protect our body from causing of the disease because our immune system produces antibodies against that antigen so when the pathogen enters our body these antibodies attack on that and prevent them of causing infection in the body so that's why injecting an antigen has to be done from the childhood to prevent diseases.
Hi,
The correct answers should be:
Electrons are smaller than protons
The majority of an atom’s mass is in the nucleus
Protons and neutrons are about the same size.
The first option is not true since in the picture you can see three different kinds of particles, while the second one is false since different electrons can occupy different energy levels and the same electron can “jump” from one energy level to another one if stimulated.
Hope this helps! If my answer was not clear enough or you’d like further explanation, please let me know. Also, English is not my first language so I’m sorry for any mistakes.
Answer: Has a metallic luster and has a black streak.
Explanation:
Protists are eukaryotic organisms that cannot be classified as a plant, animal or fungus. They are mostly unicellular, but others like algae are multicellular. Protists have mitochondria responsible for respiration to produce energy to be used by cells. Additionally, they can be parasites and mostly prefer aquatic or moist environments. They may be classified as animal-like protists (heterotrophs and have ability to move), Plant-like (autotrophs that photosynthesize) and fungi-like (heterotrophs with cells that have cell wall and reproduce by spore forming). Protists reproduce by asexual means (e.g. budding) or sexually. Therefore, in this case we may conclude that they are all parasites and reproduce sexually or asexually.
