PERTUMBUHAN DAN PERKEMBANGAN- KELAS 9 SMP

Summary

This educational video explains the differences between growth and development, focusing on both humans and animals. Growth refers to the irreversible increase in size and cell number, while development involves maturation and changes that are reversible. The video also covers the stages of human life, from fertilization to adulthood, emphasizing puberty and aging. Additionally, it delves into animal reproduction types, metamorphosis, and plant growth processes like germination and meristematic growth. The script concludes with interactive questions that reinforce key concepts about human and animal development, as well as plant growth.

Takeaways

• 😀 Growth refers to the increase in the number and size of cells, which is irreversible and measurable. An example of growth is the increase in height.
• 😀 Development is the process of maturation that is reversible and qualitative, such as the development of reproductive abilities during puberty.
• 😀 The life cycle of humans includes stages: baby, child, teenager, and adult. Each phase involves different physical and emotional changes.
• 😀 In the early years after birth, babies experience rapid growth in their nervous and motor systems, including milestones like sitting, crawling, and talking.
• 😀 Puberty is the transition from childhood to adulthood, marked by the development of primary and secondary sexual characteristics in both males and females.
• 😀 In adulthood, physical growth stops, but changes such as aging and the decrease in reproductive abilities begin, especially around the ages of 30-50.
• 😀 Animals undergo different reproductive methods: oviparous (egg-laying), ovoviviparous (eggs hatch inside the mother), and viviparous (giving birth).
• 😀 Metamorphosis in animals can be either perfect (holometabolous) or imperfect (hemimetabolous), affecting how animals develop from eggs to adults.
• 😀 Perfect metamorphosis involves distinct stages: egg, larva, pupa, and imago. Imperfect metamorphosis includes egg, nymph, and imago with less noticeable changes.
• 😀 Plant growth begins with germination, and growth types include primary growth (apical meristem) and secondary growth (lateral meristem) that occurs in dicotyledonous plants.
• 😀 Factors that influence growth and development include internal factors like genes and hormones, and external factors like light, nutrients, oxygen, and temperature.

Q & A

What is the difference between growth and development?

Growth refers to an increase in the number and size of cells, which is irreversible and quantitative. An example of growth is an increase in height. Development, on the other hand, is a process towards maturity that is reversible and qualitative. It includes processes like differentiation and specialization in sex cells, which cannot be measured.

What happens in the human life cycle?

The human life cycle includes several phases: baby, child, teenager (puberty), and adulthood. During these stages, there are significant changes in height, motor skills, language, and reproductive abilities. For example, after puberty, primary and secondary sexual characteristics develop, and in adulthood, the body reaches stability.

How does the process of human fertilization and development begin?

Human development begins with fertilization, where sperm and egg cells fuse to form a zygote. This zygote then undergoes mitosis and becomes a morula, which develops into a blastula, and later a gastrula. These processes continue until a fetus is formed, which eventually leads to birth.

At what stage in life does a human experience the most rapid growth?

The most rapid growth occurs in the first 1 to 2 years of life after birth, especially in the nervous and motor systems. During this period, the baby undergoes significant developmental milestones like sitting, crawling, standing, and walking.

What happens during puberty in humans?

Puberty is the transitional phase from childhood to adulthood, marked by the emergence of primary and secondary sexual characteristics. In females, this includes the start of menstruation, and in males, sperm production begins. Secondary sexual characteristics, such as body hair, also appear.

What is the role of the placenta in viviparous animals?

In viviparous animals, the placenta is the channel that facilitates the exchange of nutrients, oxygen, and metabolic waste between the mother and the developing embryo. This allows the embryo to develop inside the mother's body until it is ready for birth.

How do oviparous animals reproduce?

Oviparous animals lay eggs that develop outside the mother's body. These eggs have a hard shell for protection, and the embryo inside gets nutrition from the yolk. After the embryo matures, the egg hatches outside the mother's body.

What is metamorphosis, and how does it differ between animals?

Metamorphosis is the process of gradual change in shape during the growth and development of some animals. There are two types: holometabolous (perfect metamorphosis) where animals go through distinct phases (egg, larva, pupa, imago), and hemimetabolous (imperfect metamorphosis) where the phases are less different (egg, nymph, imago).

Do monocotyledonous plants experience secondary growth?

No, monocotyledonous plants do not experience secondary growth because they lack cambium tissue. Secondary growth occurs only in dicotyledonous plants, which have cambium for lateral growth.

What factors influence the growth and development of living organisms?

Growth and development are influenced by both internal and external factors. Internal factors include genes and hormones, while external factors consist of light, nutrients, oxygen, water, humidity, and temperature.