Biology Questions

Tooth Enamel is the hardest and most highly mineralized substance in the human body. It is a tissue and not a bone. This tissue has high mineral content which makes it hardest substance.

Femur and Temporal bone of the skull are the hardest bones of the human body.

Nostoc is a prokaryote. Prokaryotic cells lack membrane bound organelles and well organized nucleus, that is nuclear envelope is absent in these cells.

The nuclear envelope, also known as the nuclear membrane, a bilayer membranes which surrounds the nucleus, and in eukaryotic cells it encases the genetic material.

Mushrooms are heterotrophs. They are not plants or autotrophs.

Every living thing that exists need energy in order to live. This energy ultimately comes from the sun, and only plants, or autotrophs, can directly use this energy to make food. Those organisms that cannot harness the sun's energy are known as heterotrophs.

Mushrooms belong to kingdom Fungi and are heterotrophs because they decompose and consume nutrients from the soil. They are not green so they cannot photosynthesize

For this reason, mushrooms and all other fungi are heterotrophs.

Eukaryotic cells contain membrane-bound organelles, including a nucleus. Eukaryotes can be single-celled or multi-celled, such as you, me, plants, fungi, and insects.

Whereas Prokaryotic cells do not contain a nucleus or any other membrane-bound organelle. Bacteria are an example of prokaryotes.

Here from the above options, Algae is an Autotroph.

Autotrophs : 

An Autotroph is also called as Producer, is an organism that produces complex organic compounds from simple substances present in its surroundings, generally using energy from light or inorganic chemical reactions.