Answer:
A. gravity
Explanation:
gravity is a force that makes things go downwards in this case Jeannie put her soccer ball on the ground on the side of the hill, the hill was in the top hence the ball went downward
lymphocytes are specialized T cell ,B cell, and natural killer cell .
these cells are distinguished from other lymphocytes by a protein on their surface known as the B cell receptor .these protein is specialized to recognize and attach to specific antigens.
Answer:
The correct answer will be option- synaptonemal complex.
Explanation:
The tetrad arrangement of the genetic material in an organism is mediated by a highly conserved structure known as the synaptonemal complex. The synaptonemal complex is formed during the prophase I of the meiosis I which attaches the chromatin of the homologous chromosomes.
The synaptonemal complex is a proteinaceous structure which is formed by the two lateral ladders like elements with a central portion composed of the central element. The chromatin gets attached to the lateral elements while the central a portion bridge space between the two ladders thus help in the formation of the tetrad.
Thus, option- synaptonemal complex is the correct answer.
Answer:
sarcoplasmic reticulum deteriorates and ATP production is stopped
Explanation:
Rigor mortis is the third stage of death characterized by stiffening of joints and muscles in body. The stiffening occurs because muscles are not able to return to the relaxed state. There are two reasons for rigor mortis, depletion of ATP and increase in calcium concentration in cytosol. Due to these factors the actin-myosin crossbridge is not able to break and the muscles remain in contracted state.
Sarcoplasmic reticulum deteriorates and calcium is released into the cytosol. Sarcolemma ( covering of muscle fiber ) also breaks down releasing extra calcium into the cytosol. Calcium is responsible for formation of actin-myosin cross bridge and when its concentration increases the bridge is formed continuously leading to stiffening of muscles and joints.
Answer:
D. Changes in the environment changed each morph's ability to evade predation in different ways.
Explanation:
The moth species<em> Biston betularia</em> has two color morphs, or variants. One has a speckled white and black color, while the other is all black. Over the period of time, the distribution of moths dramatically changed between 1900 and 1950 in such a way that black morph became dominant but speckled morphs became very much declined in abundance. The reasons behind this change was heavy industrial pollution in UK between 1900 and 1950.
When the environment became very polluted, dark and blackish, the speckled moth had more chanced of getting eaten by predators thats why they declined in number as compared to black morphs. On the other hand, backgrounds of grime and soot made black morphs less visible to the predators and they survived well. This is an excellent example of natural selection that only those specie better survive that have the ability to cope better with adverse environmental fluctuations.
Therefore, option D is best option.
Hope it help!