Which statement BEST describes the role of casparian strip in mineral ion uptake?
It enhances water uptake by increasing the surface area of the root.
It prevents water loss from the xylem back into the cortex.
It facilitates passive diffusion of all minerals into the stele.
It forces water and minerals to enter the symplast, allowing for selective uptake by endodermal cells.
Related Questions
The process of mineral ions moving from one part of the plant to another is primarily driven by:
Diffusion and osmosis
Active transport and transpiration pull
Gravity and capillary action
Passive transport and root pressure
Which statement BEST describes the role of casparian strip in mineral ion uptake?
It enhances water uptake by increasing the surface area of the root.
It prevents water loss from the xylem back into the cortex.
It facilitates passive diffusion of all minerals into the stele.
It forces water and minerals to enter the symplast, allowing for selective uptake by endodermal cells.
Which of the following is a micro-nutrient required by plants?
Calcium
Magnesium
Manganese
Potassium
Which condition would MOST significantly inhibit the translocation of sucrose in phloem?
Decreased sucrose concentration in source cells
Increased sucrose concentration in sink cells
Application of a metabolic inhibitor that blocks ATP synthesis in companion cells
Exposure to light
A researcher is studying phloem transport in a plant using radioactive . After introducing the radioisotope to a mature leaf, where would the LEAST radioactivity be detected after a short period?
Apical meristem
Young developing leaves
Roots
Mature leaf cells lacking plasmodesmatal connections to the phloem
Direction of translocation of organic food or solutes, is
Upward
Downward
Radial
All of these
Which element is LEAST likely to be remobilized within the plant?
Nitrogen
Phosphorus
Potassium
Calcium
Researchers observed that inhibiting phloem unloading in a developing fruit resulted in a decrease in sucrose transport to that fruit. However, the transport of certain amino acids to the fruit was unaffected. Which explanation is MOST likely?
Amino acids are transported through the xylem, not the phloem.
Amino acid transport is solely driven by diffusion, unaffected by phloem unloading mechanisms.
Amino acids and sucrose share the same transporters, but amino acids have a higher affinity.
Amino acids are unloaded via a different mechanism than sucrose, potentially utilizing specific transporters independent of sucrose unloading.
Which of the following is NOT a factor affecting mineral uptake by plants?
Soil pH
Temperature
Light intensity
Microbial activity
The process by which mineral ions are transported from the soil to the xylem is primarily:
Diffusion
Osmosis
Active transport
Passive transport
