Which of the following is a direct evidence of evolution? MCQ with Answer and Explanation

Explanation:
The juxtaglomerular apparatus (JGA) is a specialized structure where the distal convoluted tubule (DCT) comes into contact with the afferent arteriole. It consists of juxtaglomerular cells (modified smooth muscle cells in the afferent arteriole that secrete renin), macula densa cells (modified DCT cells that sense NaCl concentration), and extraglomerular mesangial cells. It plays a crucial role in regulating blood pressure and glomerular filtration rate via the renin-angiotensin-aldosterone system.

Explanation:
Bryophytes (mosses, liverworts, hornworts) are often called the 'amphibians of the plant kingdom' because, although they can live on land, they absolutely require water for the completion of their life cycle, specifically for the swimming of male gametes (antherozoids) to reach the female gamete (egg) during fertilization. Algae are mostly aquatic, while pteridophytes and gymnosperms are better adapted to terrestrial life.

Explanation:
Homologous organs share a common ancestral origin and structural plan but may have different functions (e.g., human arm, whale flipper, bat wing). This indicates divergent evolution. Analogous organs have different origins but similar functions (e.g., wings of birds and insects) due to convergent evolution. Vestigial organs are reduced and non-functional, like the human appendix.