Radicle (baby root) enters ground. "Gravitropism" tells it which way is down.
Seed leaves (cotyledons) and stem go up, also via gravitropism - plus, they seek heat.
At the tips of both the roots and the emerging stem are areas known as apical meristems. Thest are where certain growth hormones tell the plant's cells to divide.
Just behind this leading edge, is the "zone of elongation". This is where other hormones tell the new cells what to do next. In the stem thy might be told to become a leaf cell, a petiole cell, a fiber cell... In the root, the same thing happens - cells turn into root-hair cells, storage cells, epidermal cells...
At a certain age in a plant's life, environmental triggers will tell the plant to begin producing a new set of hormones. These hormones tell the plant that it is in the prime of its life (for and annual), or it is the best time of the season (in perennials) to reproduce.
These hormones act on the apical meristems and tell them to begin producing flowers, instead of leaves. Female flowers produce ovaries/eggs. Male flowers produce pollen. When the pollen makes it to a female's ovary, they combine and create a fertilized seed. And it all starts over again...
Seeds wait to germinate until three needs are met: water, correct temperature (warmth), and a good location (such as in soil). During its early stages of growth, the seedling relies upon the food supplies stored with it in the seed until it is large enough for its own leaves to begin making food through photosynthesis. The seedling's roots push down into the soil to anchor the new plant and to absorb water and minerals from the soil. And its stem with new leaves pushes up toward the light:
The germination stage ends when a shoot emerges from the soil. But the plant is not done growing. It's just started. Plants need water, warmth, nutrients from the soil, and light to continue to grow.
Plant parts do different things for the plant.
Roots
Roots act like straws absorbing water and minerals from the soil. Tiny root hairs stick out of the root, helping in the absorption. Roots help to anchor the plant in the soil so it does not fall over. Roots also store extra food for future use.
Stems
Stems do many things. They support the plant. They act like the plant's plumbing system, conducting water and nutrients from the roots and food in the form of glucose from the leaves to other plant parts. Stems can be herbaceous like the bendable stem of a daisy or woody like the trunk of an oak tree.
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Seed germinates.
Radicle (baby root) enters ground. "Gravitropism" tells it which way is down.
Seed leaves (cotyledons) and stem go up, also via gravitropism - plus, they seek heat.
At the tips of both the roots and the emerging stem are areas known as apical meristems. Thest are where certain growth hormones tell the plant's cells to divide.
Just behind this leading edge, is the "zone of elongation". This is where other hormones tell the new cells what to do next. In the stem thy might be told to become a leaf cell, a petiole cell, a fiber cell... In the root, the same thing happens - cells turn into root-hair cells, storage cells, epidermal cells...
At a certain age in a plant's life, environmental triggers will tell the plant to begin producing a new set of hormones. These hormones tell the plant that it is in the prime of its life (for and annual), or it is the best time of the season (in perennials) to reproduce.
These hormones act on the apical meristems and tell them to begin producing flowers, instead of leaves. Female flowers produce ovaries/eggs. Male flowers produce pollen. When the pollen makes it to a female's ovary, they combine and create a fertilized seed. And it all starts over again...
Seeds wait to germinate until three needs are met: water, correct temperature (warmth), and a good location (such as in soil). During its early stages of growth, the seedling relies upon the food supplies stored with it in the seed until it is large enough for its own leaves to begin making food through photosynthesis. The seedling's roots push down into the soil to anchor the new plant and to absorb water and minerals from the soil. And its stem with new leaves pushes up toward the light:
The germination stage ends when a shoot emerges from the soil. But the plant is not done growing. It's just started. Plants need water, warmth, nutrients from the soil, and light to continue to grow.
Plant parts do different things for the plant.
Roots
Roots act like straws absorbing water and minerals from the soil. Tiny root hairs stick out of the root, helping in the absorption. Roots help to anchor the plant in the soil so it does not fall over. Roots also store extra food for future use.
Stems
Stems do many things. They support the plant. They act like the plant's plumbing system, conducting water and nutrients from the roots and food in the form of glucose from the leaves to other plant parts. Stems can be herbaceous like the bendable stem of a daisy or woody like the trunk of an oak tree.
Through a process called germination.