What are heterotrimeric G proteins?

What are heterotrimeric G proteins?
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1 Answer

Answer :

G proteins with three different subunits, designated as alpha, beta, and gamma.
Alpha and gamma subunits attach to the plasma membranes via lipid anchors. In
the absence of a signal, the entire GDP-bound G protein complex binds a nearby
GPCR. Once activated, GDP bound to the alpha subunit is replaced by GTP, and
the GTP-bound alpha subunit and beta-gamma dimer dissociate.
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Last Answer : There are eukaryotic cells without nucleus and others with more than one nucleus. Osteoclasts, the cells responsible for resorption of the osseous matrix, for example, are multinucleate cells; ... cells. Cell Nucleus Review - Image Diversity: cell nucleus miltinucleate cells enucleated cells

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Description : What is autophagic intracellular digestion ?

Last Answer : Why is this type of intracellular digestion intensified in an organism undergoing starvation? Autophagic intracellular digestion is the cellular internal digestion of waste and residual materials. In general ... obtain from its own constituent materials the nutrients necessary to stay alive.

What is heterophagic intracellular digestion ?

Description : What is heterophagic intracellular digestion ?

Last Answer : How is this process accomplished? Heterophagic intracellular digestion is the breaking into smaller substances of external substances engulfed in the cell by pinocytosis or phagocytosis. Phagosomes or pinosomes fuse ... with the plasma membrane and liberates its waste in the exterior space.

What is the main cell organelle involved in cell digestion ?

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Last Answer : What are the properties of that organelle that enable it to the task? The organelles responsible for intracellular digestion are the lysosomes. Lysosomes are vesicles that contain digestive enzymes ... digested and then digestion takes place. Cell Digestion Review - Image Diversity: lysosomes

What is intracellular digestion ?

Description : What is intracellular digestion ?

Last Answer : Intracellular digestion, or cellular digestion, is the breaking in the interior of the cell of big molecules coming from outside or even from the own cell metabolism into smaller ... is classified into two types: heterophagic intracellular digestion and autophagic intracellular digestion.

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What are some examples of secretory cells ?

Description : What are some examples of secretory cells ?

Last Answer : Endocrine and exocrine pancreatic cells, thyroid and parathyroid endocrine cells, adenohypophysis, adrenal and pineal endocrine cells, the many types of gastric exocrine and endocrine cells, the mucous secretory cells ... of the ovaries and testicles, etc., are all examples of secretory cells.

Which cell organelles are well-developed in secretory cells ?

Description : Which cell organelles are well-developed in secretory cells ?

Last Answer : In secretory cells, like the secretory cells of endocrine glands, organelles related to production, processing and exportation of substances are widely present and well-developed. These ... protein synthesis between the cytoplasm and the nucleus. Rough endoplasmic reticulum Golgi apparatus

What is meant by cellular secretion ?

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Last Answer : Cell secretion is the elimination to the exterior of substances produced by the cell (for example, hormones, mucous, sweat, etc.)

What is cyclosis ?

Description : What is cyclosis ?

Last Answer : Cyclosis is a type of internal cell movement in which an oriented flow of circulating material is created and maintained in the cytoplasm by the action of microfilaments. Cyclosis is more easily observed in plant cells. Cytoskeleton and Cell Movement - Image Diversity: cyclosis

What are some examples of movement created by the contraction of sarcomeres of the muscle cells ?

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Last Answer : The handling of a cup of coffee, the peristaltic movements of the bowels, the cardiac beats and even a smile are examples of movement created by contraction of the sarcomeres of the muscle cells. This contraction is a type of cell movement.

How do the amoeboid movements occur ?

Description : How do the amoeboid movements occur ?

Last Answer : What are examples of beings and cells that use such movements for locomotion? Amoeboid movements are created by cytoplasmic movements and plasma membrane projections called pseudopods. Their formation ... in the inflammatory process. Cytoskeleton and Cell Movement - Image Diversity: pseudopods

What are cilia and flagella ?

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Last Answer : How do these structures acquire movement? What are some examples of ciliated and flagellated cells in humans? Cilia and flagella are structures found in some prokaryotes as well in some eukaryotic ... the ovule. Cytoskeleton and Cell Movement - Image Diversity: ciliated cell flagellate cell

What are cell movements ?

Description : What are cell movements ?

Last Answer : How are these movements created? Cell movements are movements performed by cell structures, like the movements of cilia and flagella, the pseudopod movements (in amoeba, macrophages, etc. ... action, by differences of viscosity among cytoplasmic regions and by intracellular contraction systems.

which substance are microtubules made ?

Description : which substance are microtubules made ?

Last Answer : In which structures and cellular processes do microtubules participate? Microtubules are made of consecutive dimers of the protein tubulin (each dimer has an alpha and a beta tubulin associated) ... also form the centrioles. Cytoskeleton and Cell Movement - Image Diversity: microtubules tubulin

What is cytoskeleton ?

Description : What is cytoskeleton ?

Last Answer : What are its main constituents in animal cells? Cytoskeleton is the cytoplasmic structure that supports the cell, keeps its shape and fixates and moves the cell organelles. It is made of an ... intermediate filaments. Cell Skeleton and Cell Movement - Image Diversity: the "cell skeleton"

Why are salt and sugar used in the production of dried meat and dried fruits ?

Description : Why are salt and sugar used in the production of dried meat and dried fruits ?

Last Answer : Substances that maintain highly hypertonic environment, like sugar and salt, are used in the production of dried meat, fish or fruits (for example, cod) because the material to be conserved is then ... the growth of populations of decomposer beings (since these beings also lose water and die).

What is deplasmolysis of plant cells ?

Description : What is deplasmolysis of plant cells ?

Last Answer : The plant cell when placed under hypertonic medium loses a great amount of water and its cell membrane detaches from the cell wall. In that situation the cell is called plasmolysed cell. When ... medium it absorbs water and becomes a turgid cell. This phenomenon is called deplasmolysis.

Since DPD ?

Description : Since DPD ?

Last Answer : SF – TP and TP is negative (< 0) its formula becomes DPD = SF + |TP|.

What is the formula of the DPD for withered ?

Description : What is the formula of the DPD for withered ?

Last Answer : shrank) plant cells? How is that situation possible? Withered plant cells are those that shrank due to loss of water by evaporation without enough replacement. In this situation the cell membrane retracts ... The cell wall moreover expands in length to stimulate the entrance of water making TP <