In an area of alpine glaciation, sinuous, sharp-edged ridges called and sharp, pyramid- like peaks called are common features. arêtes; horns horns; hanging valleys tarns; cirques cirques; arêtes

In an area of alpine glaciation, sinuous, sharp-edged ridges called aretes and sharp, pyramid- like peaks called horns are common features.

Explanation:

The glaciers in a valley form various features due to erosion. Two of these features are the aretes and horns.

When two glaciers gradually wear away, a willowy ridge is made which separates one valley from another. This is known as the Arete. For example, The “Garden Wall” made in the Glacier National Park, Montana

When several Aretes crumble, horns are formed. The horns can be seen as the peaks on the top of the mountains. E.g The Matterhorn in Switzerland

c.) polymerase chain reaction

- "unlike the original dna fingerprinting method, dna profiling does not use restriction enzymes to cut the dna. instead it uses the polymerase chain reaction (pcr)? to produce many copies of specific str sequences. pcr is an automated procedure that generates lots of copies of a specific sequence of dna."