Sometimes called molecular photocopying the polymerase chain reaction is a fast and inexpensive technique used to amplify copy small segments of DNA.
<span>Selective breeding (also called artificial selection) is the process by which humans use animal breeding and plant breeding to selectively develop particular phenotypic traits (characteristics) by choosing which typically animal or plant males and females will sexually reproduce and have offspring together. (Domesticated) animals are known as breeds, normally bred by a professional breeder, while domesticated plants are known as (varieties), cultigens, or cultivars. Two purebred animals of different breeds produce a (crossbreed). Flowers, vegetables and fruit-trees may be bred by amateurs and commercial or non-commercial professionals: major crops are usually the provenance of the professionals. </span>
The xylem is made from dead, hollow cells.
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Tracheids and vessel elements are the main components of xylem witch have a function to transport water. Those are elongated dead cells at maturity (without protoplast) with a thick, strengthened cellulose cell wall and a hollow lumen. Even though they are dead they still maintain a function, because are being protected by surrounding living cells.</span>
Answer:
The correct order is:
- <em>1. A hematoma forms at the </em><em>fractured area</em><em>.</em>
- <em>2. A mass of tissue containing </em><em>cells that produce collagen fibers forms</em><em>. These collagen fibers extend across the broken bone and attach the pieces back together.</em>
- <em>3. </em><em>Osteoblasts and osteoclasts</em><em> arrive at the fracture and begin to produce bone tissue there.</em>
- <em>4. The broken bone begins to take the shape it had prior to the fracture.</em>
Explanation:
After the fracture of a bone several events occur that involve the regeneration and remodeling of the broken bone:
- Hematoma in the fracture area is produced by the bleeding of the bone marrow, especially when it occurs in long bones.
- The collagen fibers are intended to initiate the repair process, trying to join the bone fragments that have separated. The purpose of this is to build a soft tissue base on which the new bone will grow.
- Osteoblasts and osteoclasts are responsible for the process of ossification and remodeling, respectively. Only a bone scar will remain at the fracture site.
- With the process of ossification and remodeling, the bone acquires the same shape it had before the injury.
This whole process is necessary for the morphological and functional recovery of a bone when it has suffered a fracture.
Answer:
C. Water enters the roots, gets transported through the stem, and evaporates through the leaves
Explanation:
The process of transpiration within the plants has multiple steps. In order to get to the water, the plants use their roots, thus they manage to get it from the soil. From the roots, the water is then transported to the stem, and through the stem is transported throughout all of the plant, most importantly to the leaves. Once the water has been used, and the temperature is high enough, it evaporates through the pores of the leaves. This is part of the water cycle, and it is a very nice example of the interaction between four spheres, the hydrosphere, geosphere, biosphere, and atmosphere.