Ethylene
Explanation:
Introduction
The growth and development of plants under varied environmental conditions determine agricultural production. The growth, development, and senescence of plant’s organs can influence crop production by modulating photosynthesis, nutrient remobilization efficiency, and harvest index (Paltridge et al., 1984; Jing et al., 2005; Iqbal et al., 2012). Phytohormones have been shown to increase growth and yield of plants. The phytohormone ethylene controls growth and senescence of plants (Reid, 1995; Lutts et al., 1996; Thompson et al., 1998; Pierik et al., 2006; Masood et al., 2012; Nazar et al., 2014). Ethylene is regarded as a multifunctional phytohormone that regulates both growth, and senescence. It promotes or inhibits growth and senescence processes depending on its concentration, timing of application, and the plant cell
Answer:
that lightning sparked chemical reactions in Earth's early atmosphere. The early atmosphere contained gases such as ammonia, methane, water vapor, and carbon dioxide. Scientists hypothesize
The second one, I took the test already. And I got it right. But just negate it. Causijg more soil erosion.
<span>1. temperature
2.water purification
3. succession
4. alien species
5. conduct a survey of a species population in an ecosystem
6. adopt ecological conservation practices</span>
Answer: Polyploidy
Explanation:
Polyploidy is defined as the phenomenon by which cells, tissues or organisms with three or more complete sets of chromosomes originate. Such cells, tissues or organisms are called polyploids.
If the genomes of a polyploid species come from the same ancestral species, it is said to be autopolyploid or autoploid. And if they come from two different ancestral species, it is said to be allopolyploid or alloploid. <u>Depending on the number of complete chromosome sets that the species has it is called triploid (3X), tetraploid (4X), pentaploid (5X), hexaploid (6X) and so on, where X is the monoploid number, and not to be confused with the haploid number.
</u>
Redundant genetic elements of polyploid organisms can be transformed into single copies by sub-functionalization, neofunctionalization mechanisms or by the appearance of certain mutations.
<u>Two populations are sympatric when they exist in the same area and thus frequently encounter one another. </u>In general, different species cannot interbreed and produce healthy and fertile offspring due to barriers known as reproductive isolation mechanisms. Polyploidy speciation is common in plants but rare in animals. So, animal species are much less tolerant of changes in ploidy. For example, human embryos that are triploid or tetraploid are not viable, cannot survive.
