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Carbohydrates and Low-Carb Diets
Carbohydrates are vital part of a healthy diet. Carbohydrates do not cause weight gain unless they are eaten in excess. Low-carb diets are dietary programs which regulate carbohydrate intake to prevent weight gain.
5,534 Questions
What does carbohydrates and fats and proteins contain?
Carbohydrates provide energy for the body, fats serve as a concentrated form of energy storage, and proteins are essential for building and repairing tissues in the body. Each of these macronutrients plays a vital role in supporting various functions within the body and are required for overall health.
What is the carbohydrate in plant cell walls?
Plant cells have cell walls composed mainly of cellulose.
CELL MEMBRANE:- A thin, transparent, electron microscopic, elastic, regenerative and selectively permeable membrane, which forms the outermost covering of the cell organelles, called cell membrane or plasma membrane or plasma lamella. It lies just below the cell wall in the plant cell and forms outermost covering in the animal cell.
Chemical composition of cell membrane:- Chemically, cell membrane are lipoproteinous i.e. they are chiefly composed of lipids and proteins. Lipid constitutes (40-79) %, protein (20-70) %, carbohydrates (1-5) % and water 20%. Phospholipids are the major lipids present in the cell membrane. The other lipids are Sphignolipids, Glycerol, Sterol, etc. The proteins are globular, structural, carrier and enzymatic. Carbohydrates are branched or unbranched Oligosaccharides.
Some important structural model of cell membrane:-
A. Lamellar Model:-
i.Sandwich model:-This model was proposed by Danielli and Davson in 1935. This model was based on the physical and the chemical properties of the cell membrane. It states that: →cell membrane is a trilaminar structure having a phospholipid bilayer sandwiched by the two surfaces layer of the protein molecules.
→ protein molecules are globular structures and provide stability to the cell membrane. →each phospholipid molecules have hydrophilic heads and hydrophobic tails. → the hydrophilic head of phospholipid molecules faces towards the opposite direction associated with protein molecules, and the hydrophobic tails held together by Vander Waal Force.
ii.Unit membrane concept:-This model was proposed by Robertson in 1959. It is the improvement over Danielli and Davson model. It states that:- → all cell membrane have trilaminar structure. → the mucoid protein lie towards the external surface and the non-mucoid protein lie towards the internal surface. → the thickness of cell membrane is 75 Å having 35 Å phospholipid bilayer and 20 Å each protein layer.
The lamellar model has not explained: →permeability to the water →protein and lipid ratio →active transport →unit membrane concept.
B.Fluid mosaic Model: - It is the recent model of cell membrane proposed by Singer and Nicolson in 1972. It states that "plasma membrane is formed of protein icebergs in the sea of lipids". It's statements are:
→cell membrane is trilaminar and proteinous structure.
→phospholipid bilayer is fluidy in nature in which phospholipid molecules show: - transitional and flip-flop movement.
→each phospholipid molecules have two specific ends; ●hydrophilic head of glycerol ●hydrophobic tail of fatty acid.
→hydrophilic head of phospholipid molecules are directed oppositely, while the hydrophobic tails faces each other.
→proteins are globular and are of two types: - ●Extrinsic or peripheral proteins ●Intrinsic or integral proteins.
→carbohydrates (Oligosaccharides) are associated with outer surface of plasma membrane in the form of glycolipids or glycoproteins. They play important role in blood grouping, immune response, cancer and rejection of transplanted organs.
Functions of Cell membrane:- Cell membrane is selectively permeable membrane which has following functions:-
1. Cell adhesion:-
ü Compartmentalization: Cell wall help in the partition of the different cells, which is known as compartmentalization.
ü Bounding semi-fluid substances of the cell
2. Ion conductivity:-
ü Passive transport: It is a mode of membrane transport which occurs according to concentration gradient without any energy. It is of following types:-
*Osmosis: It is a process of movement of mater molecules from higher water concentration to lower water concentration through semi permeable membrane.
*Diffusion: It is the movement of ions or molecules from higher concentration to the lower concentration due to the tangency of molecules to spread uniformly. Both simple and facilitated diffusion occur through the cell membrane. E.g. Exchange of gases in cellular respiration (simple diffusion), entry of glucose into RBC through the agency of membrane protein (facilitated diffusion).
ü Active transport: It is a mode of membrane transport which is energy gradient and requires energy. E.g. Salt uptake by plant cell.
üEndocytosis: It is the process of active intake of material by membrane. It is of two types:
*Pinocytosis: It is the intaking process of large sized liquid particles through membrane. It is also known as cell-drinking.
*Phagocytosis: It is the intaking process of large sized solid particles through membrane. It is also known as cell-eating.
ü Exocytosis: It is the expelling of materials from cell through cell membrane. It is also known as cell-vomiting or Ephagy.
3. Cell signaling: - Cell signaling is a part of a complex system communication that governs basic cellular activities and coordinates cell actions. The ability of cells to perceive and correctly respond to their microenvironment is the basis of development, tissue repair, and immunity as well as normal tissue homeostasis. Errors in the cellular information processing are responsible for diseases such as cancer, autoimmunity and Diabetes. By understanding cell signaling, diseases may be treated effectively and, theoretically, artificial tissues may be created.
4. Locomotion:- The extension and folding of cell membrane help in the cellular pseudopodial locomotion in Amoeba, W.B.C. of blood, macrophages (phagocytes),etc. and undulatory locomotion shown by some mammalian cells such as fibroblasts.
Carbohydrate macromolecules are composed of long chains of?
sugar molecules. These sugar molecules are linked together to form complex structures like starch, glycogen, and cellulose. Carbohydrates are a major source of energy for the body and play important roles in cell structure and communication.
Why human body does not storage protein?
the human body does store protein, but it doesn't keep the protein structure, it turns it to fat, the body's only storage is adipose tissue (fat cells) the reason why the body doesn't store pure protein is because it can't get energy off it, the body's storage system is designed for energy.
Why the human body needs protein?
Proteins are essential for the body to build and repair tissues, as well as to make enzymes, hormones, and other important chemicals. They also play a key role in maintaining healthy skin, hair, and nails, and are necessary for proper immune function and muscle development. Without enough protein, the body cannot function optimally.
Is the process of combining oxygen with another material to produce chemical weathring?
The process of combining oxygen with another material to produce chemical weathering is known as oxidation. This process can lead to the breakdown of minerals, rocks, and other materials through chemical reactions with oxygen in the presence of water or moisture. Oxidation can result in the formation of new minerals, alteration of the original material, and weakening of rocks through the breakdown of components.
What is the monomer of proteins and nucleic acids?
Monomer of protein = amino acid
monomer of nucleic acid is a nucleotide, which is made up of a sugar, phosphate, and a nitrogen base.
No. It is a polysaccharide also known as animal starch.
What are organisms that derive their chemical energy from the process of chemosynthesis?
Organisms that derive their chemical energy from the process of chemosynthesis include certain bacteria, archaea, and some specialized extremophiles. These organisms use inorganic compounds such as hydrogen sulfide, methane, or ammonia to produce energy through chemical reactions instead of relying on sunlight for photosynthesis.
What is carbohydrate fermentation?
CARBOHYDRATES FERMENTATION ARE IDENTICALTO THOSE OF RESPIRATION.the process begin with glycolysisin which the glucose molecule is breaken in to pyvuric acid.. there are to types * alcholic fermentation. * lactic acid fermentation
What is the function of complex carbohydrates?
1. Starch (Complex Carbohydrate) is broken down by the body into sugars that can be used by the body.
2. Glucose (Complex Carbohydrate) can be broken down to provide a quick source of glucose.
What element is found in both nucleic acids and proteins?
Nitrogen is found in both nucleic acids (DNA, RNA) and proteins. In nucleic acids, nitrogen is present in the nitrogenous bases (adenine, guanine, cytosine, thymine, and uracil). In proteins, nitrogen is found in the amino groups of amino acids, which are the building blocks of proteins.
In what bonds is the chemical energy stored in fats and in carbohydrates?
The chemical energy in fats and carbohydrates is stored in the bonds between their molecules. In fats, the energy is stored in the ester bonds of triglycerides, while in carbohydrates, it is stored in the glycosidic bonds between sugar molecules. When these bonds are broken through metabolism, energy is released for cellular processes.
What is the principle function of dietary carbohydrates to provide?
The principle function of dietary carbohydrates is to provide energy. Dietary sugars and starches are called protein sparing. A dietary protein can be used for protein synthesis and other vital processes.
A carbohydrate forming the cell wall is what?
Cell walls are composed of cellulose, what is colloquially called "fiber". It is a polysaccharide made of glucose monomers. It has beta glucose chains contrasting with the alpha glucose of starch. Because of its bond structure, the chain is indigestible for most organisms and provides rigid support.
What organelle helps read the code for making proteins?
Ribosomes are the organelles that help read the code for making proteins. They are responsible for translating the mRNA sequence into a specific amino acid sequence, which eventually leads to protein synthesis.
What enzyme breaks down polypetides?
Enzymes that break down proteins are called a protease. There are many different enzymes that break down many different polypeptides. Usually they will end in the suffix "-in".
How is excess glucose stored in the body and why is it stored this way?
Excess glucose is stored in the body as glycogen, primarily in the liver and muscles. This is the body's way of storing energy for later use. When the body needs energy, it can quickly break down glycogen back into glucose for fuel.
What proteins on surface of cells have carbohydrates attached to protein?
At the heart of the immune response is the ability to distinguish between "self" and "non-self." Every cell in your body carries the same set of distinctive surface proteins that distinguish you as "self." Normally your immune cells do not attack your own body tissues, which all carry the same pattern of self-markers; rather, your immune system coexists peaceably with your other body cells in a state known as self-tolerance. This set of unique markers on human cells is called the major histocompatibility complex (MHC). There are two classes: MHC Class I proteins, which are on all cells, and MHC Class II proteins, which are only on certain specialized cells.
Is nucleotide classified as a carbohydrate?
A nucleotide is not classified as a carbohydrate. A nucleotide is a building block of DNA and RNA, which are nucleic acids. Carbohydrates are nutrients that typically are composed of carbon, hydrogen, and oxygen.
What is the function of the specific carbohydrates that are attached to the cell membrane?
The function of the specific carbohydrates that are attached to the cell membrane are to provide oxygen membrane. They also provide some fixed energy to various functions of the cell membrane.
What do carbohydrates provide in plants?
Carbohydrates are really any individual sugar molecule (monosaccharides) or strand of sugar molecules (polysaccharides). The monosaccharides are made by a plant cell through photosynthesis. These monosaccharides are either stored in plant starch (very small amount), used by the plant for growth and energy, or converted into cellulose, a long polysaccharide that is extremely rigid and impossible to break down without the help of specialized bacteria.
What are starches and sugars that provide energy?
Carbohydrates are the starches and sugars that provide energy. Starches are complex carbohydrates that give you extended energy and sugars are simple carbohydrates that give you a quick burst of energy.
What is a long chain of sugar molecules called?
It is called macromolecule, such as proteins, DNA and cellulose.
