Answer:
B
Explanation:
i am sorry if this is wrong
Answer:
III. Condensation of chromosomes begins.
I. Synapsis occurs.
II. Crossing-over is completed.
IV. Separation of homologous chromosomes begins
Explanation:
The prophase I of meiosis I begins with the condensation of chromosomes. The process of compaction makes the individual chromosomes visible and the stage is called leptotene.
Leptotene is followed by zygotene of prophase I during which the homologous chromosomes are paired together. The process is mediated by the synaptonemal complex. As the homologous chromosomes are paired, each pair is visible as a tetrad as each of the chromosomes of a pair has two sister chromatids.
The exchange of part of chromatids occurs during crossing over. Crossing over is the event of the pachytene stage of prophase I. After crossing over, the homologous chromosomes begin to separate from each other during diplotene but stay paired at the points of crossing over. These points are called chiasmata. Diakinesis of prophase I is marked by the dissolution of chiasmata.
Answer:
c) melatonin
Explanation:
Melatonin its a hormone formed by the pineal gland, which regulates an individual wake cycles and sleep. Jetlag alters the hormone function leading to an alteration with the body clock of the persom.
Jetlag is a sleep disorder common to those who travel swiftly over several time zones. It is not a permanent sleep disorder. Its due to the body's internal clock lacking sync with cues generated in a different time zone, Cues may be due to light exposure and how often the person eats.
A basic factor on ones internal clock is sunlight. It controls the regulation of melatonin which aid in synchronizing cells in the body.
Specific cells of the tissue at retina moves the light signals the thypothalamus.
At night, the hypothalamus signal to the pineal gland to produce melatonin. At daylight hours, the reverse is the case.
Answer:
ER is found in both animals and plants
Explanation:
the endoplasmic reticulum is found in both cells of animals and plants
The hotspots are regions, where the plumes of magma are present just below the lithosphere. The plume of the magma is the particles of the volcano and the gases, which is erupted during the volcanic eruption. It is generated by the fragmentation of the magma. Once, it reaches the lithosphere, it get spreaded laterally.
The plumes at the hotspots are present just below the tectonic plates, a high temperature r heat and the low pressure causes the rocks present in the lithosphere to melt resulting in volcanic eruption. At hotspot, the melting of rock takes time, sometimes it is very slow, due to the presence of various tectonic plates. Hence, the plumes can remain stationary for a very long period of time without erupting.
So, the first blank can be filled with Lithosphere and the second blank can be filled with Stationary.
