Red blood cells do not contain mitochondria. how do red blood cells generate most of their atp?
What is anaerobic respiration | physiology | biology
Adenosine triphosphate (ATP), a high-potential-energy compound, is the main carrier of chemical energy in most animal cells. In general, the energy needed to synthesize ATP molecules comes from very complicated fuel molecules. Fats, proteins, and carbohydrates are the three types of molecules that the human body uses to generate the energy needed to drive ATP synthesis.
In mammals, mitochondria are the primary site of ATP synthesis, though some ATP is also generated in the cytoplasm. Proteins are broken down into amino acids, and carbohydrates are broken down into glucose. Mitochondria degrade fatty acids, amino acids, and pyruvate (the end result of glucose degradation in the cytoplasm) into several intermediate compounds, as well as the reduced electron carrier coenzymes NADH and FADH2 through a series of oxidation-reduction reactions (Figure 1). The intermediates enter the tricarboxylic acid (TCA) cycle, where NADH and FADH2 are formed. The electron transport chain oxidizes these reduced electron carriers, consuming oxygen and requiring ATP synthesis in the process (Figure 1). This is known as oxidative phosphorylation.
Part 1 : cellular level of organization | cell structure
The importance of maternal mtDNA inheritance in human evolution and migration research has been proven. Similarities inherited in generations of offspring can be tracked down a single line of ancestors for several generations thanks to maternal transmission. According to research, all humans alive today have mitochondrial genome fragments that can be traced back to a single woman ancestor who lived between 150,000 and 200,000 years ago. Scientists believe that this woman lived among other women, but that as the population grew, her mtDNA became randomly superseded by that of other women due to genetic drift (chance variations in gene frequency that influence the genetic constitution of small populations). Researchers have used variations in mtDNA passed down over centuries to deduce the geographical origins and chronological migrations of various human populations. Humans migrated from Asia to the Americas 30,000 years ago may have been stranded on Beringia, a large region that included a land bridge in the present-day Bering Strait, for as long as 15,000 years before settling in the Americas, according to mitochondrial genome analysis.
Your body’s molecular machines
Explanation: While red blood cells are eukaryotic cells, they lack mitochondria. This is due to the fact that red blood cells transport oxygen. Mitochondria, on the other hand, need oxygen to generate ATP. If red blood cells had mitochondria, the oxygen that the cells were attempting to transport would be used up.
Explanation: Although all of the response options are valid, only one supports the endosymbiotic theory. According to this widely accepted hypothesis, mitochondria began as single-celled prokaryotes that were absorbed by larger cells. These cells formed a symbiotic relationship that ultimately gave rise to the eukaryotic cells we see today. To support this theory, a statement must establish a link between mitochondria and the prokaryotes from which they evolved, such as the fact that they have similar DNA structures.
To research genetic defects in humans, scientists use a technique called Flourescent In-Situ Hybridization, or FISH. FISH is a method that uses spectrographic analysis to assess the presence or absence of genetic material in human cells, as well as its relative abundance.
What is cellular respiration – how do cells obtain energy
Erythrocytes (erythro– = “red”; –cyte = “cell”) are specialized cells that circulate in the body, supplying oxygen to cells. They are produced from stem cells in the bone marrow. Red blood cells are small biconcave cells that do not have a nucleus or mitochondria when mature and are just 7–8 m in diameter in mammals. A nucleus is also present in red blood cells in birds and non-avian reptiles.
The iron-containing protein hemoglobin is responsible for the red color of blood, as shown in Figure 1a. This protein’s primary function is to transport oxygen, but it also transports carbon dioxide. At a rate of around 250 million molecules of hemoglobin per cell, hemoglobin is packed into red blood cells. Each hemoglobin molecule binds four oxygen molecules, resulting in one billion molecules of oxygen carried by each red blood cell. In the five liters of blood in the human body, there are approximately 25 trillion red blood cells, which can hold up to 25 sextillion (25 1021) molecules of oxygen at any given time. The absence of organelles in erythrocytes in mammals frees up more space for hemoglobin molecules, and the absence of mitochondria avoids the use of oxygen for mitochondrial respiration. Anucleated red blood cells are present only in humans, and some mammals (such as camels) have nucleated red blood cells. The ability to undergo mitosis is a benefit of nucleated red blood cells. Anucleated red blood cells metabolize anaerobically (without oxygen), using a primitive metabolic mechanism to generate ATP and improve oxygen transport efficiency.