Explanation

Endocardium lines the inner chambers of the heart.

Myocardium is the thick, muscular middle layer responsible for contraction.

Epicardium is the outermost protective layer.

Together, these three layers make up the complete structure of the heart wall.

Explanation

The poem "Music, When Soft Voices Die" was written by Percy Bysshe Shelley, a major English Romantic poet.

It expresses the idea that beautiful experiences and memories live on even after they're gone.

Explanation

These lines are taken from "Elegy Written in a Country Churchyard" by Thomas Gray.

The stanza reflects on the unrecognized potential of people buried in a quiet graveyard — possibly capable of greatness but lost to obscurity.

Explanation

Chlorella is a unicellular green alga, meaning the entire organism consists of a single cell.

Bacteria are also unicellular but are prokaryotic, while Chlorella is eukaryotic.

Viruses are not made of cells at all.

Explanation

He said that he would pay the next day.

"Will" changes to "would" in indirect speech.

"Tomorrow" changes to "the next day" in reported speech.

Explanation

Root hairs increase the surface area of roots for efficient absorption of water and minerals from the soil.

They play a key role in anchoring the plant and facilitating nutrient uptake.

Explanation

The sentence is in past simple tense (did discourage) — passive form becomes was/were + past participle.

So, correct passive structure: "Why were they discouraged by you?"

Explanation

With "Does", we always use the base form of the verb — so "have", not "has".

Correct sentence: "Does anyone have a pencil I could borrow?"

Explanation

Neutron is a neutral particle, meaning it has no electric charge.

Because of this, it didn't respond to electric or magnetic fields, making its detection difficult and late compared to protons and electrons.

Explanation