Answer:
definition with benefit is given below of
1st. gravitropism
2nd. phototropism
3rd. thigmotropism
4th. photoperiod
Explanation:
1st is gravitropism
gravitropism is process in which plant grow in the direction that gravity act
It is also called geotropism
and
Gravitropism is important for plants because it directs the roots to grow in the downward direction that is important for obtaining nutrients
2nd is phototropism
phototropism is the process in which plant growth directed by the light
and
we know plants need light to carry out photosynthesis
so Phototropism direct the growth of the stem and branch toward sunlight
3rd is thigmotropism
thigmotropism is the directional change in growth of plant in response to a touch stimulus
and
thigmotropism is especially important for climbing plant that is use support to climb up
4th is photoperiod
photoperiod is the physiological change in organism in the response to length of the day and night
and
it play important role to determining the physiological developmental process in the plant such as budding and tuberization
<span>A fossil leaf that is made only of carbon preserved between two rock layers is called carbon film fossil.
</span>Characteristic of the carbon film fossils is that they are primarily composed of carbon. The fossil leaf has usually lost <span>internal components (cell walls and internal cell structures ).</span>
Жила была царевна но туда ей бросил лёд
Tin, because it has five energy levels with four electrons in the fifth level
.
Explanation:
Tin has an electronic configuration as
1s2,2s2,2p6,3s2,...........4d10, 5s2,5p2
They have four valence electrons in their outer shell
Among the four diagrams given Tin is least reactive because the atomic radius of tin is largest among all four options. Due to large atomic radius electronegativity decreases and hence Tin is the least reactive element among Neon, Chlorine, gallium and tin.
The electronegativity of an element is its tendency to complete its octet by attracting electrons towards itself. Also tin is at the lowest place in the periodic table among all the four mentioned elements, its ionization energy is also low hence less electronegative and least reactive.
