More than 70 percent of species recorded on the Earth are animals and only 22 percent species are plants. There is quiet a large difference in their percentage. This is because animals have adapted themselves to ensure their survival in changing environments in comparison to plants. For example, insects and other animals have developed a complex nervous system to control and coordinate their body structure. Also, repeated body segments with paired appendages and external cuticles have made insects versatile and have given them the ability to survive in various habitats as compared to other life forms.
Fill in the blanks:
(a) Humans reproduce __________. (asexually/sexually)
(b) Humans are__________. (oviparous/viviparous/ovoviviparous)
(c) Fertilization is __________ in humans. (external/internal)
(d) Male and female gametes are __________. (diploid/haploid)
(e) Zygote is __________. (diploid/haploid)
(f) The process of release of the ovum from a mature follicle is called__________.
(g) Ovulation is induced by a hormone called the __________.
(h) The fusion of male and female gametes is called _____________.
(i) Fertilisation takes place in _____________.
(j) Zygote divides to form _____________which is implanted in uterus.
(k) The structure which provides vascular connection between fetus and uterus is called ____________.
What is biosphere Reserves?
question is how animals have achieved greater diversification ? why animals were able to adapt themselves and how they developed those features necessary for their diversity?