what are the membrane structures that function in active transport

The transport of materials across the cell membranes with the help of energy is called active transport. Both diffusion and osmosis are passive transport mechanisms, not requiring energy. Active transport helps in the trans..

The human heart is a muscular, cone-shaped, hollow organ about the size of a fist (about 12cm in length and 9cm in breadth). The heart is situated behind the sternum, between the lungs in the thoracic cavity. The heart is tilted slightly such that its apex is towards the left side. External Hea..

Summary - In lower organisms, there is no transport system as the cells are in touch with the surrounding medium. The transport is by the physical processes like diffusion, osmosis, etc. With the advancement in structure, the organisms have to evolve methods to tr..

Plasma Membrane - The plasma membrane or cell membrane surrounds the cell contents in all types of cells. It is a multipurpose covering composed of phospholipids and proteins. fig. 16.4 - Cell Membrane Apart from the plasma membrane, an eukaryotic c..

The cell membrane and the membranes of various cell structures exhibit the same structure and as such perform the same functions. However, the amount and arrangement of phospholipids and proteins varies in different cells and organelles. This variat..

Transport of Minerals - Minerals are absorbed from the soil along with water as they are dissolved in water. They are taken up in the ionic form . For example, potassium is taken up as K + ions. They are transported through the xylem along with the water. Some of the mineral ion..

Minerals are absorbed from the soil along with water as they are dissolved in water. They are taken up in the ionic form . For example, potassium is taken up as K + ions. They are transported through the xylem along with the water. Some of the mineral ions like the nitrates enter into the..

Unit Membrane Concept - The molecular structure of cell membrane is still not clearly known. Several models have been proposed from time to time to explain its structure based on its physico-chemical properties. In the year 1935 Danielli and Dawson proposed t..

1. Peptide hormones Insulin has a profound influence or carbohydrate metabolism. It facilitates entry of glucose and other sugars into the cells by increasing penetration of cell membranes and augmenting phosphorylation of glucose. This decreases glucose concentration in blood and insuli..

This process is much faster and requires energy. A membrane pump operates across the cell membranes which transports the nutrients from the lumen of the intestine into the cells. This transport occurs with the help of ATP molecules. The carrier proteins in t..