Sickel cell anemia is an inherited disease that is due to a base substitution mutation in a gene.
Answer:
Channel proteins and Carrier proteins
Explanation:
These are type of membrane proteins that transcend the entire length of phosphoslipid bi- layer in the plasma membrane.They facilitate the movement of ions and molecules across the walls of the plasma membranes.
Generally, substances like glucose, amino acids, are too large to pass through the phopholipid bilayers. Likewise ions of potassium, sodium calcium, because of their polarities can not pass through either. They are ferried across the phospholipid by group of protein structures called channel proteins. Some are also transported across by carrier proteins. The process by which these protein structures aided the diffusion of substances across the phospholipid bilayer is called Facilitated diffusion.
Channel proteins are pores, that are filled with water molecules with the entrance well gated. That is the entrance is controlled by part in the inner structure of the protein which can open or close the pores like a gate to control the movement of ions across it. e.g Sodium channels are gated for movement of sodium ions by voltage or ligands(chemicals) during nervous transmission to elicits action potential. Like wise Potassium channels allow diffusion of potassium ions across the phospholipid bilayers. it gates are shut when sodium channels are open; this regulate ion exchange.
Their structures are well fixed in shape , specific to the substance or ions being transported;and the rate of diffusion depends on the like hood of opening of the gate or closure.
Carrier molecules also in the membranes do not have a fixed shape, and their transport direction is determined by the direction of concentration gradients. Thus they can flip on either sides of the membranes to aid diffusion across. Their movement can be both passive and active, and the rates of diffusion depends on the number of available carrier proteins in the membrane. They are also specific to the ions they transport.And are not gated,
Therefore these two membrane integral proteins facilitate movements of substances across the phospholipild bilayers
Explanation:
Cell Structure
Creatures in kingdom Animalia are all multicellular organisms with eukaryotic cells that have nuclei and organelles. Unlike plants and fungi, animal cells do not have a cell wall. In addition, with the exception of sponges, cells are divided into specialized tissues or organs.
Movement
All Animalia members are mobile at some point in their lives. Motion is achieved through the musculoskeletal system and is one of the factors that allow animals to live in diverse ecosystems including oceans, mountains and deserts. Movement is achieved in various ways including legs, fins and wings.
Food and Respiration
All members of kingdom Animalia are "heterotrophs." They obtain nourishment from other organisms and digest the food internally. In addition, animals utilize aerobic respiration for cellular energy and food breakdown on a molecular level. Oxygen works at a molecular level to complete the metabolic processes necessary to turn fat and sugar into energy for the cells.
Answer:
Explanation:
Al igual que la mitosis, la meiosis es una forma de división celular eucariota. Sin embargo, estos dos procesos distribuyen el material genético entre las células hijas resultantes de formas muy diferentes. La mitosis crea dos células hijas idénticas, cada una de las cuales contiene el mismo número de cromosomas que su célula madre.