Which Organelles Have Enzymes That Degrade Aging Cell Components?

Lysosomes are small, spherical organelles that contain digestive enzymes that break down macromolecules such as nucleic acids, proteins, and polysaccharides. They are essential for the cell’s recycling and disposal of unwanted material, such as old cell parts or invading bacteria and viruses. Lysosomes are membrane-enclosed organelles that contain an array of enzymes capable of breaking down all types of biological polymers, including proteins, nucleic acids, carbohydrates, and lipids.

Lysosomes are involved in various cell processes and are responsible for breaking down excess or waste. They are composed of lipids and proteins, with a membrane protecting the rest of the cell from harsh digestive enzymes. The lysosome is the cell’s recycling center, acting as a sphere full of enzymes ready to hydrolyze whatever it is.

Although some organelles, such as chloroplasts, centrosomes, and vacuoles, traditionally were not organized as organelles, researchers have discovered biomolecular condensates in prokaryotic cells, which traditionally were defined as not containing organelles.

In the mid-2000s, scientists realized that some organelles don’t need to be wrapped in a membrane. Lysosomes are membrane-bound organelles that contain an array of enzymes capable of breaking down all types of biological polymers, including proteins, nucleic acids, carbohydrates, and lipids.

In conclusion, lysosomes are crucial for the cell’s recycling and disposal of unwanted materials, such as old cell parts and foreign invaders.

What organelles digest old organelles?

The correct option is C Lysosomes Lysosomes play a key role in destroying old organelles within the cell and thus allow them to be replaced with fresher, more effective ones.

What organelle breaks down food and old cell parts?

Lysosomes are subcellular organelles found in eukaryotic cells responsible for the digestion of macromolecules, old cell parts, and microorganisms. They are surrounded by a membrane that maintains an acidic environment via a proton pump. Lysosomes contain a variety of hydrolytic enzymes ( acid hydrolases) that break down macromolecules, such as nucleic acids, proteins, and polysaccharides. These enzymes are active only in the lysosome’s acidic interior, protecting the cell from self-degradation in case of lysosomal leakage or rupture. Lysosomes originate from the trans-Golgi network, a region responsible for sorting newly synthesized proteins. They fuse with membrane vesicles that derive from one of three pathways: endocytosis, autophagocytosis, and phagocytosis. Endocytosis takes extracellular macromolecules into the cell, forming membrane-bound vesicles called endosomes that fuse with lysosomes. Autophagocytosis removes old organelles and malfunctioning cellular parts from a cell, enveloped by internal membranes that fuse with lysosomes. Phagocytosis is carried out by specialized cells that engulf large extracellular particles and target them for lysosomal degradation. Many of the products of lysosomal digestion, such as amino acids and nucleotides, are recycled back to the cell for use in the synthesis of new cellular components.

What breaks down old organelles in a cell?

Lysosomes. The lysosome is an organelle that contains digestive enzymes and acts as the organelle-recycling facility of an animal cell. It breaks down old and unnecessary structures so their molecules can be reused.

What enzymes break down old organelles for reuse?

Lysosomes are membrane-enclosed organelles that contain an array of enzymes capable of breaking down all types of biological polymers—proteins, nucleic acids, carbohydrates, and lipids. Lysosomes function as the digestive system of the cell, serving both to degrade material taken up from outside the cell and to digest obsolete components of the cell itself. In their simplest form, lysosomes are visualized as dense spherical vacuoles, but they can display considerable variation in size and shape as a result of differences in the materials that have been taken up for digestion ( Figure 9. 34 ). Lysosomes thus represent morphologically diverse organelles defined by the common function of degrading intracellular material.

Figure 9. 34. Electron micrograph of lysosomes and mitochondria in a mammalian cell. Lysosomes are indicated by arrows. (Visuals Unlimited/K. G. Murti.)

Lysosomal Acid Hydrolases. Lysosomes contain about 50 different degradative enzymes that can hydrolyze proteins, DNA, RNA, polysaccharides, and lipids. Mutations in the genes that encode these enzymes are responsible for more than 30 different human genetic diseases, which are called lysosomal storage diseases because undegraded material accumulates within the lysosomes of affected individuals. Most of these diseases result from deficiencies in single lysosomal enzymes. For example, Gaucher’s disease (the most common of these disorders) results from a mutation in the gene that encodes a lysosomal enzyme required for the breakdown of glycolipids. An intriguing exception is I-cell disease, which is caused by a deficiency in the enzyme that catalyzes the first step in the tagging of lysosomal enzymes with mannose-6-phosphate in the Golgi apparatus (see Figure 9. 25 ). The result is a general failure of lysosomal enzymes to be incorporated into lysosomes.

What contains enzymes that break down materials?

Lysosomes Answer and Explanation: The organelles that contain digestive enzymes that break down waste material and debris in a cell in a cell are called lysosomes.

What breaks down and digests old cell parts?

Lysosomes are membrane-enclosed organelles that contain an array of enzymes capable of breaking down all types of biological polymers—proteins, nucleic acids, carbohydrates, and lipids. Lysosomes function as the digestive system of the cell, serving both to degrade material taken up from outside the cell and to digest obsolete components of the cell itself. In their simplest form, lysosomes are visualized as dense spherical vacuoles, but they can display considerable variation in size and shape as a result of differences in the materials that have been taken up for digestion ( Figure 9. 34 ). Lysosomes thus represent morphologically diverse organelles defined by the common function of degrading intracellular material.

Figure 9. 34. Electron micrograph of lysosomes and mitochondria in a mammalian cell. Lysosomes are indicated by arrows. (Visuals Unlimited/K. G. Murti.)

Lysosomal Acid Hydrolases. Lysosomes contain about 50 different degradative enzymes that can hydrolyze proteins, DNA, RNA, polysaccharides, and lipids. Mutations in the genes that encode these enzymes are responsible for more than 30 different human genetic diseases, which are called lysosomal storage diseases because undegraded material accumulates within the lysosomes of affected individuals. Most of these diseases result from deficiencies in single lysosomal enzymes. For example, Gaucher’s disease (the most common of these disorders) results from a mutation in the gene that encodes a lysosomal enzyme required for the breakdown of glycolipids. An intriguing exception is I-cell disease, which is caused by a deficiency in the enzyme that catalyzes the first step in the tagging of lysosomal enzymes with mannose-6-phosphate in the Golgi apparatus (see Figure 9. 25 ). The result is a general failure of lysosomal enzymes to be incorporated into lysosomes.

What are the enzymes that break down?

• Amylase (made in the mouth and pancreas
• breaks down complex carbohydrates)
• Lipase (made in the pancreas
• breaks down fats)
• Protease (made in the pancreas
• breaks down proteins)

Some other common enzymes are made in the small intestine, including:

• Lactase (breaks down lactose)
• Sucrase (breaks down sucrose)

Which organelle helps to recycle old cell organelles?

Lysosomes are microscopic organelles that serve as digestion compartments for cellular materials that have exceeded their lifetime or are no longer useful. They recycle the cell’s organic material through autophagy, breaking down waste products, fats, carbohydrates, proteins, and other macromolecules into simple compounds. These compounds are then transferred back into the cytoplasm as new cell-building materials. Lysosomes utilize about 40 different types of hydrolytic enzymes, all manufactured in the endoplasmic reticulum and modified in the Golgi apparatus. They are spherical organelles contained by a single layer membrane, protecting the rest of the cell from the harsh digestive enzymes contained in the lysosomes. The cell is further protected from exposure to the biochemical catalysts present in lysosomes by their dependency on an acidic environment. The lysosomal matrix is favorable for enzymatic activity, but the neutral environment of the cytosol renders most digestive enzymes inoperative. The acidity of the lysosome is maintained with the help of hydrogen ion pumps, and the organelle avoids self-digestion by glucosylation of inner membrane proteins to prevent their degradation.

The discovery of lysosomes involved the use of a centrifuge to separate the various components of cells. Belgian scientist Christian René de Duve observed that cells released an enzyme called acid phosphatase in larger amounts when they received proportionally greater damage in the centrifuge. He suggested that the digestive enzyme was encased in a membrane-bound organelle within the cell, which he identified using electron microscope images.

What are the digestive enzymes?

Types of Digestive Enzymes. There are many digestive enzymes. The main digestive enzymes made in the pancreas include:

• Amylase (made in the mouth and pancreas
• breaks down complex carbohydrates)
• Lipase (made in the pancreas
• breaks down fats)
• Protease (made in the pancreas
• breaks down proteins)

Some other common enzymes are made in the small intestine, including:

• Lactase (breaks down lactose)
• Sucrase (breaks down sucrose)

What breaks down food waste and old cell parts?

Lysosomes are organelles that contain enzymes that break down old cell parts, or any other waste the cell needs removed. Waste materials are moved to the outer membrane of the lysosome and can then be taken in by the lysosome. The lysosome is filled with digestive enzymes that can break down the waste products.

Which organelles contain enzymes that break down old cell?

A lysosome is a membrane-bound cell organelle that contains digestive enzymes. Lysosomes are involved with various cell processes. They break down excess or worn-out cell parts.