How is the tundra different from the desert?

Tundra and desert are two of the five major biomes that exist on Earth. The others are the forest, aquatic, and grassland biomes. The desert and tundra biomes are the most similar of the five, since both receive little precipitation, support minimal vegetation, and have significantly lower nighttime temperatures. However, there are major differences that warrant the tundra and desert being classified as distinct biomes.
The major difference is the average temperature of the region. Deserts are found where temperatures are hot in the daytime. Tundra is only found in cold regions, including at high elevations in mountain ranges. Three types of tundra include arctic tundra, which is near the North Pole; antarctic tundra, which is near the South Pole; and alpine tundra, which occurs above the treeline in mountain ranges of high elevation. Deserts occur mainly at lower latitudes (nearer the equator), but some "cold" deserts occur farther north or south—for instance, in Utah and western Asia. Coastal deserts are found along the ocean—for example, in Chile.
Another difference between the two biomes is the biodiversity they support. While both have sparse flora relative to other biomes, the desert supports a greater variety of plant life—about 2,500 different species—compared to tundra, which supports only about 1,500 different species. Desert and tundra biomes have many similarities, but they have significant differences as well.
https://ucmp.berkeley.edu/exhibits/biomes/deserts.php

https://www.reference.com/science/desert-similar-tundra-62b5728a5aed3f6