Explanation

When one harmful species resembles another harmful species, it is known as Müllerian mimicry.

This type of mimicry involves two or more harmful or poisonous species evolving to look alike, reinforcing the avoidance behavior in predators.

Explanation

Ernst Haeckel introduced the recapitulation theory

Which posits that the embryonic development of an organism reflects the evolutionary history of its species.

Explanation

LH stands for Luteinizing Hormone, which is a protein hormone.

It plays a crucial role in the regulation of the reproductive system,

They including the stimulation of ovulation in females and testosterone production in males.

Explanation

Angiotensin III is part of the renin-angiotensin system, which regulates blood pressure and fluid balance.

The juxtaglomerular cells, located in the kidneys, release renin in response to a decrease in sodium chloride concentration in the distal tubules.

Renin then catalyzes the conversion of angiotensinogen to angiotensin I,

Which is further converted to angiotensin II, and subsequently to angiotensin III.

This cascade helps in regulating blood pressure and sodium balance.

Explanation

In the taxonomic hierarchy, the rank that comes directly below the class is the order.

The full hierarchy from broader to more specific categories is:

1. Domain
2. Kingdom
3. Phylum
4. Class
5. Order
6. Family
7. Genus
8. Species.

Explanation

In gastropods (such as snails and slugs), the veliger stage is a crucial developmental phase following the trochophore stage.

During the veliger stage, the larva develops a shell and ciliated structures that help it swim.

Explanation

The nacre is continuously deposited onto the inner surface of the shell

The iridescent nacreous layer is commonly known as the mother of pearl

Nacre is secreted by the epithelial cells of the mantle tissue of various molluscs.

The layers of nacre smooth the shell surface and help defend the soft tissues against parasites 

Explanation

It is estimated that about 99.9% of all species that have ever existed on Earth are now extinct.

This figure underscores the vast extent of extinction events throughout:

• Earth's history
• reflects the dynamic 
• often unstable nature of life on the planet.

The remaining 0.1% of species are the ones that are still extant today.

Explanation

The fluid mosaic model describes the structure of the plasma membrane of both prokaryotic and eukaryotic cells.

This model illustrates the membrane as a dynamic and flexible structure with various proteins floating in or on the fluid lipid bilayer.

Explanation

Jaws were absent in the class Ostracodermi.

Ostracoderms are an extinct group of jawless fish that lived in the Paleozoic era.

They are characterized by their armored bodies and lack of jaws, unlike later vertebrates that evolved jaws.