TRANPORTASI TUMBUHAN KELAS 11 SMA #Jaringantumbuhan # transportasi #biologi

Summary

This biology lesson focuses on the transport of substances in plants, including the processes of guttation and transpiration. It explains the importance of regulating water content within plants and introduces two main transport pathways: extravascular (horizontal) and intravascular (vertical). The lesson highlights key plant structures involved, such as the xylem and phloem, and theories like the Vital-Dixon, Joly, and root pressure theories that explain how water and nutrients move. Factors like humidity, temperature, light, wind, and soil moisture that influence transport speed are also discussed, providing a comprehensive understanding of plant hydration and nutrient movement.

Takeaways

• 😀 Transport in plants is essential for regulating water content and nutrient distribution.
• 🌱 Guttation is the release of water droplets from plant leaves, usually observed in the morning.
• 🌞 Transpiration is the evaporation of water from leaves, typically occurring during the day.
• 🌍 There are two main types of transport: extravascular (horizontal) and intravascular (vertical).
• 💧 Extravascular transport occurs in the roots and involves pathways like the epidermis, cortex, and endodermis.
• 🔄 The symplastic pathway involves the movement of water through living cells connected by plasmodesmata.
• 🧱 The apoplastic pathway involves water movement through dead cells, such as cell walls and intercellular spaces.
• 🌳 Intravascular transport takes place in the stem and involves xylem and phloem tissues.
• 💦 Xylem transports water and minerals from roots to leaves, while phloem transports food (photosynthesis products) from leaves to other plant parts.
• 📚 There are three theories explaining the upward movement of water: Vital Theory, Cohesion-Tension Theory (Transpiration), and Root Pressure Theory.
• 🌬️ Factors affecting transport speed include humidity, temperature, light, wind, and soil water content.

Q & A

What are the two main processes that help plants regulate water content?

The two main processes are gutasi and transpiration. Gutasi involves the release of water droplets from the plant, often seen in the morning, while transpiration is the evaporation of water from the plant during the day.

What is the difference between extravascular and intravascular transport in plants?

Extravascular transport occurs outside the vascular system, typically in the roots, and does not involve vascular bundles like xylem and phloem. Intravascular transport, on the other hand, happens within the vascular system, with xylem and phloem transporting substances vertically through the plant.

Why is the extravascular transport also known as horizontal transport?

Extravascular transport is called horizontal transport because it mainly takes place in the root system, where substances move horizontally through the tissues like root hairs, epidermis, cortex, and endodermis.

What are the two types of pathways in extravascular transport?

The two types of pathways are the symplast pathway and the apoplast pathway. The symplast pathway involves living cells and uses plasmodesmata to connect them, while the apoplast pathway involves dead cells, moving substances through the cell walls and intercellular spaces.

What role does plasmodesmata play in the symplast pathway?

Plasmodesmata are channels that connect plant cells, allowing substances to move from one living cell to another in the symplast pathway. This pathway connects the root's epidermis, cortex, endodermis, and pericycle.

How does the apoplast pathway differ from the symplast pathway?

The apoplast pathway involves the movement of substances through dead cells, specifically through cell walls and intercellular spaces, while the symplast pathway involves living cells connected by plasmodesmata.

What substances are transported through the xylem and phloem in plants?

Xylem transports water and minerals from the roots to the rest of the plant, while phloem transports food (mainly sugars) produced through photosynthesis from the leaves to other parts of the plant.

What are the three main theories explaining how water and minerals move in plants?

The three main theories are: 1) The Cohesion-Tension Theory, which explains water movement through transpiration and cohesion of water molecules; 2) The Root Pressure Theory, which involves the pressure created by the roots to push water upwards; and 3) The Capillarity Theory, which describes the movement of water through narrow spaces due to surface tension.

How does transpiration influence the movement of water in plants?

Transpiration creates a pulling force that helps move water from the roots to the leaves. As water evaporates from the leaves, it creates a negative pressure that draws more water upwards through the plant.

What factors affect the rate of water transport in plants?

The rate of water transport is influenced by humidity, temperature, light intensity, wind speed, and soil moisture. For example, high humidity slows transport, while strong winds and high temperatures increase transpiration and water movement.