Transport in Plants and Humans - Vocabulary Flashcards

This study guide provides key vocabulary terms related to transport in plants and humans, including definitions and explanations to aid learning.

Xylem

Conducts mainly water and minerals from the roots up to other parts of the plants and also provides support.

Phloem

Conducts organic food from the leaves both up and down the plant.

Xylem

Conducts mainly water and minerals from the roots up to other parts of the plants and also provides support.

Phloem

Conducts organic food from the leaves both up and down the plant.

Tracheids

Single cells that are elongated, tapering, and lignified, providing mechanical strength and support.

Xylem Vessels

Conducting units of angiosperms, long tubular structures formed by the fusion of several vessel cells end to end.

Xylem Parenchyma

Involved in food storage, deposition of crystals, radial transport of food and water, and gaseous exchange.

Phloem Tissues

Composed of living cells, responsible for translocating solutions of organic solutes throughout the plant.

Sieve Tube Elements

Cells which fuse end-to-end to form sieve tubes, facilitating the translocation of organic solutes.

Companion Cells

Cells that provide support to sieve tube elements, forming a functional unit with them.

Diffusion

Movement of substances from an area of higher concentration to an area of lower concentration.

Osmosis

Diffusion of water through living membranes from high potential to low potential through a semipermeable membrane.

Plasmolysis

Shrinkage of the protoplasm of a cell due to exosmosis when placed in hypertonic solution.

Apoplast Pathway

Extracellular pathway between the cell walls of adjacent cells.

Casparian Strips

Bands of cell wall material composed of suberin, deposited in the radial and transverse walls of root endodermal cells, preventing apoplast movement.

Symplast Pathway

Pathway works through plasmodesmata, which are cytoplasmic microscopic channels between cell walls of adjacent cells.

Vacuolar Pathway

Water moves from vacuole to vacuole through neighbouring cells, crossing the symplast and apoplast in the process.

Adhesion

The attractive force between water molecules and other substances.

Cohesion

Attractive force between water molecules, forming weak hydrogen bonds that collectively produce high cohesion.

Tension

A negative pressure that pulls water from locations where the water potential is greater.

Transpiration

The loss of water vapours by evaporation from aerial parts of the plants.

Starch Sugar Hypothesis

Explains the opening and closing of stomata based on the conversion of starch to sugar and vice versa.

Influx of K+ ions Hypothesis

Explains the opening and closing of stomata through the movement of potassium ions into and out of the guard cells.

Source

The part of the plant from which sucrose and amino acids are translocated (e.g., green leaves and stem).

Sink

The part of the plant where sucrose and amino acids are being translocated (e.g., yellow leaves, fruits, seeds, and roots).

Water Potential

Kinetic energy of water molecules; water moves from a region of higher potential to lower potential.

Osmotic (Solute) Potential

Measure of the change in water potential due to the presence of solute molecules (always negative).

Pressure Potential

Pressure exerted by the protoplast against the cell wall of the plant.

Plasmolysis

Shrinkage of protoplast due to exosmosis of water.

Ascent of Sap

The pull of water and dissolved minerals through the xylem tissue towards the leaves.

Root Pressure

Pressure created by the active secretion of salts and other solutes from other cells into the xylem sap.

Imbibition

The uptake of water by dry cell walls of plant cells, leading to an increase in volume without dissolving.

Bleeding

Flow of sap from the cut ends or surfaces when certain plants are cut, pruned, tapped, or otherwise wounded.

Pericardium

Double membranous sac enclosing the heart, protecting it and preventing overextension.

Epicardium

The thin, outer layer of the heart wall comprised of a serous membrane.

Myocardium

The thick, middle layer of the heart composed of cardiac muscle cells.

Endocardium

The smooth, inner layer of the heart chambers.

SA node

Sinoatrial node, impulse-generating (pacemaker) tissue located in the upper dorsal wall of the right atrium of the heart. initiates the electrical impulses for heartbeat and keeps the heart in motion.

AV node

Atrioventricular node, an electrical relay station between the atria and the ventricles. Electrical signals from the atria must pass through the AV node to reach the ventricles.

Pulmonary semilunar valve

The valve allows blood to flow from the right ventricle into the pulmonary trunk and prevents blood from flowing back into the right ventricle.

Aortic semilunar valve

The valve allows blood to flow from the left ventricle into the aorta and prevents blood from flowing back into the left ventricle.

Vaso vasorum

A network of small arteries supply blood to the arteries themselves.

Active Transport

Movement of materials across capillary walls requiring energy.

Diffusion

Movement of materials across capillary walls from an area of high concentration gradient to low concentration gradient.

Interstitial Fluid

Fluid in the interstitium, derived from filtration and diffusion from the capillaries. Serves as a medium for material exchange between blood and body cells.

Artificial pacemaker

Battery operated device producing an electric stimulus is used to provide continued rhythmic impulses to the ventricles that take over the control of ventricles.