Answer:
Space carries a massive atmosphere that can be adverse for planets. For example, stars tend to flow gases knows as stellar winds, high-intensity rays known as the cosmic rays flow through space, solar winds from the sun are also very harmful.
For a planet to be habitable, the magnetic field is essential to deflect the solar winds and other harmful rays. Without the magnetic field, the planet would emit harmful rays from the Sun making and hence, no life would be able to sustain on it.
Answer:
20 ( B )
Explanation:
Given data:
a and b are 10 map units apart
b and c are 20 map units apart
a and c = 30 map units apart
<em>condition </em>; Triple heterozygote testcrossed
number of progeny = 1000
<u>Determine the number of double crossover result </u>
P( crossover between a and b ) = 10/100 = 0.1
P( crossover between b and c ) = 20/100 = 0.2
p( double crossover ) = 0.1 * 0.2 = 0.02
hence number of double crossovers = number of progeny * 0.02
= 1000 * 0.02 = 20
Answer:
Mitochondria originated when an ameoba like organism engulfed an aerobic proteobacterium capable of cellular respiration.
Explanation:
Endosymbiotic Theory:
- The endosymbiotic theory explains the origin of eukaryotic cells and eukaryotic organelles, particularly the chloroplast and mitochondria.
- According to this theory, a prokaryotic ameoba like organism increased in size and gradually developed infoldings of its plasma membrane. These infoldings gradually developed into an endomembrane that enclosed the genetic material and nucleus.
- This cell then engulfed a proteobacterium capable of cellular respiration. Over time, this cell thrived as oxygen increased in the atmosphere of the Earth. The proteobacterium survived as an endosymbiont and later evolved into mitochondria.
Microtubules, a structure of the cytoskeleton, are responsible for assuring that the two members of a homologous chromosome pair go to different daughter cells. During Anaphase I, the pair of homologous chromosome move to opposite sides of the cell, through a process called segregation. Microtubules emerging from a structure on the cell surface, called spindle, bind to each chromosome of the pair and ensure the separation of the pair.
The student's conclusion was incorrect because the tropical rainforest biome has an average of 200-400 centimeters or 80-100 inches of rain a year. The correct biome based on the climatograph is temperate grassland because, on average per year, this biome has 25-75 centimeters of precipitation each year. Its temperature is ranging from 0-25 degrees Celcius.