Postembryonic development and laws of ontogenesis
Answers are for parents and teachers.
1
Compare direct development and development with metamorphosis in a table (3 differences).
Direct: young resemble adults, no larva, mainly growth. With metamorphosis: a larva, a change stage, different food.
2
If a Hydra is cut into pieces and each piece grows into a new Hydra, how many new Hydras from 4 Hydras each cut into 6 pieces?
24
3
How do alcohol, nicotine and narcotic drugs harm the foetus? Write briefly.
They pass through the mother’s blood and disturb growth and brain development, raising the risk of defects.
4
What is acceleration and what are its causes?
Faster physical development and puberty of children; caused by better nutrition and living conditions.
5
What does the presence of pharyngeal arches in the human embryo show?
That vertebrates came from a common ancestor.