When a plant grows toward sunlight it is called positive phototrophism.
Answer:
<em>CHARACTERÍSTICAS </em><em> </em><em>DE </em><em>LOS </em><em>BIOELEMENTOS:</em>
<em>*</em><em>Masa </em><em>molecular </em><em>pequeña:</em><em> </em><em>esto </em><em>les </em><em>permite</em><em> </em><em>compartir </em><em>electones </em><em>de </em><em>su </em><em>capa </em><em>externa </em><em>y</em><em> </em><em>formar</em><em> </em><em>enlaces</em><em> </em><em>covalentes</em><em> </em><em>estables</em><em>.</em>
<em>*</em><em>Polaridad:</em><em> </em><em>muchas </em><em>veces </em><em>la </em><em>tienen </em><em>los </em><em>compuestos </em><em>formados.</em><em> </em><em>.</em><em>.</em><em>.</em>
<em>*</em><em>El </em><em>carbono </em><em>comparte </em><em>cuarto </em><em>electrones </em><em>formado </em><em>cuarto </em><em>enlaces</em><em> </em><em>covalentes</em><em> </em><em>muy </em><em>estable.</em>
Answer:
vestigial structures are considered evidence because scientists believe they are structures that were once used by a species ancestors but are not longer needed. these structures do not impair the organism in any way, so there is no need for evolution to get rid of them. for example, the human appendix is considered a vestigial structure.
Explanation:
:D
<span>The Syrian desert, located in the arabian peninsula area of Syria.</span>
They are rich in hydrogen and helium, they have unlimited supply of hydrogen, they have a strong gravitational pull.
Explanation:
Space where huge size of gaseous and dust cloud is present is called nebula. It is mainly made of hydrogen and helium. Nebula exist in the space which is between the stars and it is call as interstellar space.
Helix nebula is closest nebula which is near the earth. It’s distance from earth is about 700 light years.
Dark nebulae are very dense as well as cold. Nebula can be divided into dark nebula and bright nebula. The gas which is present between the stars is always combine with solid grains cosmic dust.