Answer:
Biological energy conversion in mitochondria is carried out by the membrane protein complexes of the respiratory chain and the mitochondrial ATP synthase in the inner membrane cristae. Recent advances in electron cryomicroscopy have made possible new insights into the structural and functional arrangement of these complexes in the membrane, and how they change with age. This review places these advances in the context of what is already known, and discusses the fundamental questions that remain open but can now be approached.
Mitochondria are the powerhouses of the cell. In all eukaryotes that do not depend on photosynthesis, the mitochondria are the main source of adenosine triphosphate (ATP), the energy-rich compound that drives fundamental cell functions. These functions include force generation (for example, in muscle contraction and cell division), the biosynthesis, folding and degradation of proteins, and the generation and maintenance of membrane potentials. ATP is produced on a massive scale in the human body, amounting to 50 kg per day in a healthy adult, but considerably more in a long-distance runner. ATP is generated by the mitochondrial ATP synthase from ADP and phosphate ions. These are the products of ATP hydrolysis at the sites where energy is needed in the cell. Apart from cellular respiration and ATP synthesis, mitochondria have numerous other essential functions, including the production of NADH and GTP in the citric acid cycle, the biosynthesis of amino acids, heme groups and iron-sulfur clusters or the synthesis of phospholipids for membrane biogenesis. They also act in calcium signaling [1], stress responses [2] and generally as cellular signaling hubs [3]. Not surprisingly, mitochondria play a fundamental role in human health. Mitochondrial dysfunction is the cause of severe, often maternally inherited diseases. Moreover, mitochondria are deeply implicated in apoptosis and ageing [4].
In many respects, mitochondria resemble α-proteobacteria, from which they are thought to have originated by endocytosis some 1.6 billion years ago. The most striking evidence of this evolutionary relationship is the close homology of bacterial and mitochondrial respiratory chain complexes. Mitochondria have their own genetic system, which uses a distinct DNA code that differs both from that of their bacterial ancestors and their eukaryotic hosts [5]. They have their own protein translation machinery, complete with ribosomes, tRNAs and associated protein factors that more or less resemble those of their bacterial ancestors. Very recently, the first high-resolution structure of a mitochondrial ribosome, determined by single-particle electron cryomicroscopy (cryo-EM), has revealed a fascinating patchwork of similarities to and differences from bacterial ribosomes [6]. Nevertheless, mitochondria make surprisingly little use of their specialized protein production machinery. In the course of evolution they have transferred up to 99 % of their genes to the nucleus. Today, the vast majority of mitochondrial proteins are produced in the cytoplasm and imported into the organelle by an elaborate set of protein translocases [7]. In humans, only 13 mitochondrial proteins are organelle-encoded, all of them central, hydrophobic subunits of respiratory chain complexes or of the ATP synthase.
Mitochondria are highly dynamic [8]. In the cell, they form a tubular network that constantly changes by division and fusion (Additional file 1). Both processes are accomplished by multi-component molecular machineries that include a number of dynamin-related GTPases [9, 10]. When mitochondria are isolated from cells, the network breaks up into fragments that spontaneously reseal. Isolated mitochondria are fully competent for respiration and ATP synthesis [11]. They maintain their membrane composition, organization and membrane potential, as well as the ability to fuse [12] and to import proteins [7]. We owe much of what we know about mitochondria and how they work at the molecular level to in vitro studies with isolated mitochondria, or even mitochondrial membrane fractions, which still carry out oxidative phosphorylation and ATP synthesis [13].
The composition of mitochondrial membrane consists of several proteins and phospholipids.
The major phospholipids in the mitochondrial membranes are phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylserine (PS), and phosphatidic acid (PA), as in cell membrane.Phosphatidylglycerol (PG) and cardiolipin (CL), are exclusively components of mitochondrial membrane.The composition of a eukaryotic cell membrane comprises of phospholipids, proteins, carbohydrates and cholesterol or sterols.
What is a cell membrane ?
The cell membrane is a biological membrane that separates the interior of all cells from the outside environment and protects the cell from its environment.
The eukaryotic cell membrane is a bilayer of phospholipids which is semi-permeable in nature. The mitochondria is a double membranous structure, in which the inner membrane is of crucial importance. It is highly semi-permeable (unlike the outer membrane) and consists of various proteins that are involved in the oxidative phosphorylation.To know more about cell membrane here
https://brainly.com/question/12476894
#SPJ2
Teeth of herbivores are always..................................
Select one:
a.
pointed and help them grinding plant
b.
Flat for grinding plant
c.
sharp for tearing meet
In his journey to the Galapagos Islands, Charles Darwin was amazed by the variation in the characteristics of plants and animals he encountered. In any habitat, food can be limited and the types of foods available may vary. One year, there was no rain on these islands. Many plants failed to bloom and produced no new seeds. This left mostly large, tough seeds for the finches to eat. Describe one change in beak characteristics that would most likely occur in the finch population after many generations if this change in seed size became permanent.
What stage of mitosis is depicted by the image above?
O metaphase
O cytokinesis
O telophase
O prophase
O anaphase
Answer:
Telophase 1 because of the constriction
Explanation:
The cell membrane constricts and divides the cytoplasm in half to form two cells
What stage of mitosis is depicted by the image above?
O metaphase
telophase
O prophase
O anaphase
cytokinesis
Answer:
telophase
Explanation:
because the chromatids are pulled to the opposite sides
ow do cells use food to make energy and maintain homeostasis
Answer:
Cells obtain energy through the process of cellular respiration. It is a metabolic process of conversion of the biochemical energy from the nutrients into adenosine triphosphate (ATP). ... They exchange substances with the new cells and also eliminate the wastes thereby maintaining homeostasis.
Explanation:
There are several ion transport mechanisms within the cell membrane that function to maintain proper levels of solutes inside and outside the cell. ... This system uses the energy stored in ATP to pump potassium into the cell and sodium out of the cell.
How do scientists think Prokaryotic Cells contributed to changing Earth’s atmosphere to include more oxygen?
Explanation:
Then, about 2.5 billion years ago, oxygen started getting added to the atmosphere by photosynthetic cyanobacteria. “Oxygen is produced as a waste product of photosynthesis. ... “The production and burial of plant matter over long periods causes oxygen levels to rise,” explains Poulsen
help with all of them please
number the steps for using a microscope to view a slide order from 1-11
can u zoom in cant see it
Assume that the sequence of bases in one strand of DNA molecule is a GACTTACGTACC what is the sequence of complementary bases in the other strand of DNA during DNA replication
Name three factors that can result in a decrease in the size of a population
Answer:
birth rate,death rate, immigration and emigration
A concentration of nerve cells in one area is called ?
no links
Answer:
neuron
Explanation:
In the peripheral nervous system a bundle of axons is called a nerve. In the central nervous system a bundle of axons is called a tract.
human picks up bacteria on his or her hands. The bacteria do not cause disease but do feed on the human's dead skin cells. This is an example of
Answer:
The correct answer is - Commensalism
Explanation:
Commensalism is a symbiont relationship in which there is a relationship between two organisms in which one gets benefits and the other organism is unaffected.
Human skin has many commensal bacteria that fed on dead cells of the skin. Here humans are hosts that do not get harm and bacteria rely on them for survival.
Identify ALL of the functions of proteins. Structure and is found in tendons, bones, and ligaments. Communication and works as chemical messengers such as hormones. Defense as in antibodies. Transportation and are embedded in the cell membrane to allow substances to move across the cell membrane. Enzymes that lower the activation energy of a reaction. Contraction to allow muscle and cell contraction/movement. Eicosanoid such as in regulation of blood pressure or inflammation. Steroids such as cholesterol. Glycogen for energy storage in muscles.
Answer:
Structure and is found in tendons, bones, and ligaments.
Communication and works as chemical messengers such as hormones.
Defense as in antibodies.
Transportation and are embedded in the cell membrane to allow substances to move across the cell membrane.
Enzymes that lower the activation energy of a reaction.
Contraction to allow muscle and cell contraction/movement.
Explanation:
Proteins serve many functions in living organisms.
Structure: The most abundant protein in mammals is collagen and is found throughout the body. In a major component of connective tissue such as skin, ligaments, and tendons providing strength and elasticity to these tissues. It is found also mineralized in bones and teeth.
Proteins function as hormones which are chemical messengers that mediate many cellular responses in the body. For example, the hormone insulin is a protein.
Proteins functions in the body's immune system as antibodies which recognize and initiate immune responses against diseases. The immunoglobulin such as immunoglobulin A and G are proteins.
Proteins serves as transporters to move substances across the cell memebrane. Some are found as peripheral or integral membrane proteins. Examples of transport proteins are the glucose transporters, Glut-1, Glut-2 and Glut-4 transporters.
Enzymes are proteins which catalyse the chemical reactions tanking place in an organisms. Various enzymes in the body include the hydrolases, the ligands, the leases, etc.
Contraction of the actin filaments of the muscle which are proteins, allow muscle and cell contraction bringing about movement.
A Note on the other options.
Eicosanoids are lipid molecules which serve various functions such as in regulation of blood pressure or inflammation.
Steroids such as cholesterol are lipid-derived molecules.
Glycogen for energy storage in muscles is a storage form of glucose, a carbohydrate.
All prokaryotes are _________ eukaryotes
More complex than
Smaller than
Larger than
Similar in size to
Explain how the cell division of cancer cells like these are misregulated. Identify genetic and other changes that might have caused these cells to escape normal cell cycle regulation
Answer:
Due to non-functioning of protein.
Explanation:
The cell division of cancer cells like these are misregulated because they can't be control by the proteins that is responsible for the control cell division. The cancer cells can multiply without any growth control factors, or growth-stimulating protein signals that control its growth. There are some proteins that is responsible for control of cell division but due to mutation that protein of substance stop working and the cancer cell grows uncontrollable.
The concept of _________________ has ensured that economic and environmental conditions in different countries are related and linked.
Answer:
Globalization
Explanation:
Globalization can be defined as the strategic process which involves the integration of various markets across the world to form a large global marketplace. Basically, globalization makes it possible for various organizations to produce goods and services that is used by consumers across the world.
Some examples of international economic organizations involved in global economy and trade are;
I. World Trade Organization (WTO).
II. United Nations (UN).
III. International Monetary Fund (IMF).
IV. United Nations Conference on Trade and Development (UNCTAD).
In conclusion, the concept of globalization has ensured or made it possible such that economic and environmental conditions in different countries of the world are related and linked with the intention of generating revenue and profits while providing goods and services to meet the demands or requirements of various consumers across the world.
Answer:
Globalization
Explanation:
The concept of Globalization has ensured that economic and environmental conditions in different countries are related and linked.
water moving along the ground, into and including rivers
and streams.
is it
Transpiration
Infiltration
Percolation
Surface runoff
Answer:
surface runoff is the answer
Cual es mi nota 80\68.Panama
Explanation:
81.
pasando los 50 puntos de la segunda parte ya se considera un punto más.
i need it fast
Bacteria and other micro organisms grow and produce acids. Ravi’s mouth was
checked before and 1 hour after eating, at 15 minutes intervals. It was seen that
the environment inside the mouth was becoming more and more acidic, after
every 15 minutes.
a. Explain the reason for this.
b. Suggest the possible effects of this on the teeth.
c. How can you prevent this?
Answer:
hey
Explanation:
i think its because f the bacteria forming inside the moith due to food
the teeth can detiriorate and break down
by brushing daily
Answer:
check cbse textbook gr.7 pg19
care of teeth
Explanation:
just go check it jobless sreerag
Which is a part of interphase
Answer:
B
Explanation:
S phase
IVO
1. (12.01 LC)
What is an example of a physical characteristic that scientists use to group animals?(2 points)
A. Has feathers
B. Lives on land
C. Has a social language
D. Takes care of their young
cevap b yap Hadi çabuk lenlenlen
how does the nervous system communicate with other parts of the body?
The central nervous system (CNS) is composed of the brain and the spinal cord. The central nervous system communicates with the rest of the body by sending messages from the brain through the nerves that branch off of your spine.
Explanation:
The central nervous system communicates with the rest of the body by sending messages from the brain through the nerves that branch off of your spine. You are able to move your body
7. How does your respiratory and circulatory systems attempt to maintain homeostasis
during exercise?
a. Your body produces more red blood cells to help provide energy to cells.
b. Your lungs produce more oxygen which is then delivered to the cells through the
blood.
c. You experience an increase in blood flow which provides nutrients to cells to
increase energy and remove wastes.
d. You experience an increase in breathing rate to obtain more oxygen which is
delivered to cells through the bloodstream.
Answer:a
Explanation:
The ability of an organism to survive and reproduce in its specific environment is called
O diversity
O fitness.
O fertility.
O evolution.
Answer:
fitness
Explanation:
Das wot Googoo told me.
what is the function of chromosomes
A- regulating the production of specific proteins
B- producing energy through metabolism
C- transmitting electrical signal through the body
D- controlling the rate of cellular division
how can you differentiate between littoral zone and limnetic zone in a pond ecosystem ?
Explanation:
The limnetic zone is the open and well-lit area of a freestanding body of freshwater, such as a lake or pond. Not included in this area is the littoral zone, which is the shallow, near-shore area of the water body.
Do sex-linked traits that originate from mutated genes found on X chromosome affect one sex more than the other? why/why not
Which technological tool helps earth scientists gain new knowledge about earth’s subsurface?
Group of answer choices.
A. Global positioning system
B. Digital balance
C. Ground penetrating radar
G. Hydrometer
Answer:
ground penetrating radar
Ground penetrating radar technological tool helps earth scientists gain new knowledge about earth’s subsurface. Thus the correct option is C.
What is Ground penetrating radar?Ground penetrating radar detects non-metal and metal objects, as well as voids and underground irregularities. It makes possible to measure the depth, dimensions, thickness of targets. It provides data quickly and can cover a large site area.
Ground penetrating radar can go deep up to 100 feet (30 meters) in low conductivity materials such as dry sand or granite. Moist shale, clays, and other high conductivity materials, may attenuate or absorb GPR signals, greatly decreasing the depth of penetration to 3 feet (1 meter) or less.
For more information regarding ground penetrating radar, visit:
https://brainly.com/question/6069534
#SPJ2
A seed, known as "pinhão", is the great evolutionary novelty that is present in Gymnosperms plants. Choose the correct affirmative sentence related to seeds.
Hi. Unfortunately, you didn't show the answer options, which makes it impossible for me to answer your question. However, I'm going to give you some general information about seeds that can help you find the right answer. Hope this helps you.
Seeds are structures responsible for plant proliferation. They exist only in gymnosperms and angiosperms and are absent in bryophytes and pteridophytes. All seeds are formed in the ovary of flowers as a result of the plant fertilization process.
All seeds are formed by three structures known as integument, nutrient and embryo. The embryo is what gives rise to another plant, which will grow after the seed is planted and germinates. Nutrients will be responsible for meeting the needs of the new plant during the beginning of its development. The integument, in turn, has the function of protecting the embryo.
'Complete the diagram to show the results you would see at 40°C and 60°C'
Answeryeah it’s that one
Explanation: yup, definitely that one.