Systems Physiology - AP Biology
Card 1 of 7546
What happens antibodies for a specific antigen when that antigen is presented in the body?
What happens antibodies for a specific antigen when that antigen is presented in the body?
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The immune system is very adaptive. The body has many antibodies that will each recognize different antigens. If an antibody binds to an antigen, the antibody will be copied so that the body can quickly recognize the threat if it is exposed to the antigen a second time. This process is known as the adaptive immune response.
When an antigen is presented for a second time, antibodies to the antigen are released. These antibodies bind to the antigen, labelling it for attack by immune cells and preventing it from interacting the membrane proteins on the host cells.
The immune system is very adaptive. The body has many antibodies that will each recognize different antigens. If an antibody binds to an antigen, the antibody will be copied so that the body can quickly recognize the threat if it is exposed to the antigen a second time. This process is known as the adaptive immune response.
When an antigen is presented for a second time, antibodies to the antigen are released. These antibodies bind to the antigen, labelling it for attack by immune cells and preventing it from interacting the membrane proteins on the host cells.
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An antibody can be best classified as which of the following?
An antibody can be best classified as which of the following?
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Antibodies are proteins created by the immune system in order to neutralize foreign objects. An antibody would not be classified as an enzyme because it does not catalyze chemical reactions. When a foreign pathogen enters the body, it will have foreign receptors on its surface. These foreign receptors are known as antigens. When a pathogen is destroyed, immune cells can carry a sample of the antigen to the T-cells for identification. The T-cells help activate B-cells that will synthesize an antibody against the particular antigen. The selected B-cells differentiate into plasma cells and secrete antibody proteins into the blood, which bind the antigens and label the pathogen as foreign. This label attracts other immune cells to attack and destroy the pathogen.
Antibodies are proteins created by the immune system in order to neutralize foreign objects. An antibody would not be classified as an enzyme because it does not catalyze chemical reactions. When a foreign pathogen enters the body, it will have foreign receptors on its surface. These foreign receptors are known as antigens. When a pathogen is destroyed, immune cells can carry a sample of the antigen to the T-cells for identification. The T-cells help activate B-cells that will synthesize an antibody against the particular antigen. The selected B-cells differentiate into plasma cells and secrete antibody proteins into the blood, which bind the antigens and label the pathogen as foreign. This label attracts other immune cells to attack and destroy the pathogen.
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Which of the following is true regarding menstrual cycles in individuals living in the developing world?
Which of the following is true regarding menstrual cycles in individuals living in the developing world?
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There are variations in the age of menarche by geographic location and environmental conditions. In developing countries, the age of menarche is later than in industrialized nations.
There are variations in the age of menarche by geographic location and environmental conditions. In developing countries, the age of menarche is later than in industrialized nations.
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The endometrium is a membrane in which of the following female reproductive parts?
The endometrium is a membrane in which of the following female reproductive parts?
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The endometrium is a mucus membrane in the uterus of the female reproductive tract. The endometrium changes thickness based on hormone levels and is shed during the menstrual cycle if fertilization does not occur.
The endometrium is a mucus membrane in the uterus of the female reproductive tract. The endometrium changes thickness based on hormone levels and is shed during the menstrual cycle if fertilization does not occur.
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Which of the following correctly describes the relationship between an antigen and an antibody?
Which of the following correctly describes the relationship between an antigen and an antibody?
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Antibodies are continuously made in the body in different shapes and forms. They are then sent into the blood stream to test for the presence of compatible antigens. Each antibody can only bind to one antigen, and each antigen can only bind to one antibody. Think of them like a codon-anticodon pair; there is only one possibility for them to form a perfectly complementary pair. Once the correct antibody binds to an antigen, they are tagged and used to stimulate production of more antibodies. The antibodies are only capable of binding and tagging the antigens. Cytotoxic T-cells are then able to recognize antibody binding patterns and actually destroy the infected cell.
Antibodies are continuously made in the body in different shapes and forms. They are then sent into the blood stream to test for the presence of compatible antigens. Each antibody can only bind to one antigen, and each antigen can only bind to one antibody. Think of them like a codon-anticodon pair; there is only one possibility for them to form a perfectly complementary pair. Once the correct antibody binds to an antigen, they are tagged and used to stimulate production of more antibodies. The antibodies are only capable of binding and tagging the antigens. Cytotoxic T-cells are then able to recognize antibody binding patterns and actually destroy the infected cell.
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Which of the following segments of the digestive system has the primary job of digesting food?
Which of the following segments of the digestive system has the primary job of digesting food?
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The duodenum, in the small intestine, is a site of protein, carbohydrate, and fat digestion.
The jejunum is a site of protein and fat absorption. The ileum is a site of salt, vitamin, and excess molecule absorbtion. The colon is a segment of the large intestine for water and ion absortion. Each of these work to absorb different molecules, but do not significantly contribute to their digestion.
The duodenum, in the small intestine, is a site of protein, carbohydrate, and fat digestion.
The jejunum is a site of protein and fat absorption. The ileum is a site of salt, vitamin, and excess molecule absorbtion. The colon is a segment of the large intestine for water and ion absortion. Each of these work to absorb different molecules, but do not significantly contribute to their digestion.
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During which of the following pregnancy stages can the mother begin to feel fetal movement?
During which of the following pregnancy stages can the mother begin to feel fetal movement?
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Human pregnancy can be divided into three trimesters, each categorized by different symptoms and stages of fetal development. During the second trimester of pregnancy, which occurs between 13 and 28 weeks, fetal movement can be felt. This is often called “quickening,” which is the stirring of the fetus.
Human pregnancy can be divided into three trimesters, each categorized by different symptoms and stages of fetal development. During the second trimester of pregnancy, which occurs between 13 and 28 weeks, fetal movement can be felt. This is often called “quickening,” which is the stirring of the fetus.
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Which of the following is indicative of the third trimester of pregnancy?
Which of the following is indicative of the third trimester of pregnancy?
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The third trimester of pregnancy takes place during weeks 29 and 40. During this stage of pregnancy, women continue to gain weight, the fetus moves regularly, and the fetal head descends. The descent of the fetal head is important in easing maternal breathing and positioning the fetus for future delivery.
The third trimester of pregnancy takes place during weeks 29 and 40. During this stage of pregnancy, women continue to gain weight, the fetus moves regularly, and the fetal head descends. The descent of the fetal head is important in easing maternal breathing and positioning the fetus for future delivery.
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Which of the following best describes when a pregnancy is considered to be “full term”?
Which of the following best describes when a pregnancy is considered to be “full term”?
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A woman is said to be “full term” when she is at 39 to 41 weeks of pregnancy. Medical intervention to induce labor during this time is not ideal.
A woman is said to be “full term” when she is at 39 to 41 weeks of pregnancy. Medical intervention to induce labor during this time is not ideal.
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Which of the following is a complication associated with pregnancy?
Which of the following is a complication associated with pregnancy?
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Pregnancy related medical conditions and complications are incredibly common due to strain on the mother and extreme biological changes associated with pregnancy. Examples include postpartum depression, anemia, preeclampsia, and ectopic pregnancy.
Pregnancy related medical conditions and complications are incredibly common due to strain on the mother and extreme biological changes associated with pregnancy. Examples include postpartum depression, anemia, preeclampsia, and ectopic pregnancy.
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Which portion of a neuron receives neurotransmitters from a previous neuron, signaling the need for propagation of action potential?
Which portion of a neuron receives neurotransmitters from a previous neuron, signaling the need for propagation of action potential?
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Neurotransmitters from presynaptic cells are received by the dendrites of postsynaptic cells. There are myriad dendrites on each neuron that then propagate this signal to the soma (or cell body), allowing the signal to be passed down the axon to another neuron.
Neurotransmitters from presynaptic cells are received by the dendrites of postsynaptic cells. There are myriad dendrites on each neuron that then propagate this signal to the soma (or cell body), allowing the signal to be passed down the axon to another neuron.
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A researcher applies a voltage of 20mV and generates an action potential in a neuron. He applies the same stimulus five seconds later and observes no action potential.
He then initiates another trial, applying 20mV to the neuron to generate an action potential. He waits five seconds and applies a voltage of 60mV, which causes an action potential.
What can the researcher conclude about the neuron five seconds after the initial stimulus in both trials?
A researcher applies a voltage of 20mV and generates an action potential in a neuron. He applies the same stimulus five seconds later and observes no action potential.
He then initiates another trial, applying 20mV to the neuron to generate an action potential. He waits five seconds and applies a voltage of 60mV, which causes an action potential.
What can the researcher conclude about the neuron five seconds after the initial stimulus in both trials?
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Absolute refractory period of a neuron is the period of time during which no amount of external stimulus will generate an action potential. Relative refractory period is the period of time during which only a large stimulus will generate an action potential.
In this question the neuron initially generated an action potential when 20mV was applied; however, five seconds after the initial stimulus the neuron only generated the action potential when a large stimulus (60mV) was applied. We can conclude that the neuron was in its relative refractory period. If the neuron was in its absolute refractory period, then a stimulus of 60mV shouldn’t have generated an action potential.
A neuron never becomes temporarily dead. Also, remember that once the neuron is out of its relative refractory period, the required stimulus for action potential will revert back to normal. At a later time (for example ten seconds after the initial stimulus) the neuron will only require 20mV to generate an action potential. Increasing time doesn’t necessarily increase the magnitude of the external stimuli required to produce an action potential.
Absolute refractory period of a neuron is the period of time during which no amount of external stimulus will generate an action potential. Relative refractory period is the period of time during which only a large stimulus will generate an action potential.
In this question the neuron initially generated an action potential when 20mV was applied; however, five seconds after the initial stimulus the neuron only generated the action potential when a large stimulus (60mV) was applied. We can conclude that the neuron was in its relative refractory period. If the neuron was in its absolute refractory period, then a stimulus of 60mV shouldn’t have generated an action potential.
A neuron never becomes temporarily dead. Also, remember that once the neuron is out of its relative refractory period, the required stimulus for action potential will revert back to normal. At a later time (for example ten seconds after the initial stimulus) the neuron will only require 20mV to generate an action potential. Increasing time doesn’t necessarily increase the magnitude of the external stimuli required to produce an action potential.
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Major histocompatibility molecules (MHC) are critical for the functioning of the immune system. These proteins are utilized allow for communication between the immune system and the cells. MHC I are utilized to show which cells are in fact part of the body and which are foreign. MHC II are utilized to show the immune system when there is an intruder.
MHC I molecules are derived from chromosome 6. On chromosome 6, there is a specific gene that encodes for the molecule. On the gene, there are 3 locus (A, B, C) which allows for variability in the binding site of the MHC I molecule. The MHC gene is co-dominance and therefore adds to its diversity. During development, the gene is transcribed into MHC I molecules. However, some of these are broken down and react with a particular MHC I molecule. The reaction allows for the MHC I molecule to surface onto the cellular membrane and to self-identify the protein for the cytotoxic T-cell.
After translation, MHC II molecules are transported to the endosome. When a pathogen binds to the proper MHC II binding site, these molecules are then presented to T-Helper cells. In comparison, MHC I molecules interact with endogenous antigens whereas MHC II molecules interact with exogenous antigens.
Based on the passage, where is the interaction between the MHC I molecule and the particular antigen occur?
I. Endoplasmic reticulum
II. Endosome
III. Cytoplasm
Major histocompatibility molecules (MHC) are critical for the functioning of the immune system. These proteins are utilized allow for communication between the immune system and the cells. MHC I are utilized to show which cells are in fact part of the body and which are foreign. MHC II are utilized to show the immune system when there is an intruder.
MHC I molecules are derived from chromosome 6. On chromosome 6, there is a specific gene that encodes for the molecule. On the gene, there are 3 locus (A, B, C) which allows for variability in the binding site of the MHC I molecule. The MHC gene is co-dominance and therefore adds to its diversity. During development, the gene is transcribed into MHC I molecules. However, some of these are broken down and react with a particular MHC I molecule. The reaction allows for the MHC I molecule to surface onto the cellular membrane and to self-identify the protein for the cytotoxic T-cell.
After translation, MHC II molecules are transported to the endosome. When a pathogen binds to the proper MHC II binding site, these molecules are then presented to T-Helper cells. In comparison, MHC I molecules interact with endogenous antigens whereas MHC II molecules interact with exogenous antigens.
Based on the passage, where is the interaction between the MHC I molecule and the particular antigen occur?
I. Endoplasmic reticulum
II. Endosome
III. Cytoplasm
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From the passage, the MHC I molecule's blueprint is on chromosome 6. Therefore, the DNA must have been transcribed in the nucleus then translated in the ribosome. These ribosomes are on the endoplasmic reticulum. While in the endoplasmic reticulum, some of these proteins are degraded and react with a particular MHC I molecule.
From the passage, the MHC I molecule's blueprint is on chromosome 6. Therefore, the DNA must have been transcribed in the nucleus then translated in the ribosome. These ribosomes are on the endoplasmic reticulum. While in the endoplasmic reticulum, some of these proteins are degraded and react with a particular MHC I molecule.
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Major histocompatibility molecules (MHC) are critical for the functioning of the immune system. These proteins are utilized allow for communication between the immune system and the cells. MHC I are utilized to show which cells are in fact part of the body and which are foreign. MHC II are utilized to show the immune system when there is an intruder.
MHC I molecules are derived from chromosome 6. On chromosome 6, there is a specific gene that encodes for the molecule. On the gene, there are 3 locus (A, B, C) which allows for variability in the binding site of the MHC I molecule. The MHC gene is co-dominance and therefore adds to its diversity. During development, the gene is transcribed into MHC I molecules. However, some of these are broken down and react with a particular MHC I molecule. The reaction allows for the MHC I molecule to surface onto the cellular membrane and to self-identify the protein for the cytotoxic T-cell.
After translation, MHC II molecules are transported to the endosome. When a pathogen binds to the proper MHC II binding site, these molecules are then presented to T-Helper cells. In comparison, MHC I molecules interact with endogenous antigens whereas MHC II molecules interact with exogenous antigens.
Based on the passage, where is the interaction between the MHC II molecule and the particular antigen occur?
I. Endoplasmic reticulum
II. Endosome
III. Cytoplasm
Major histocompatibility molecules (MHC) are critical for the functioning of the immune system. These proteins are utilized allow for communication between the immune system and the cells. MHC I are utilized to show which cells are in fact part of the body and which are foreign. MHC II are utilized to show the immune system when there is an intruder.
MHC I molecules are derived from chromosome 6. On chromosome 6, there is a specific gene that encodes for the molecule. On the gene, there are 3 locus (A, B, C) which allows for variability in the binding site of the MHC I molecule. The MHC gene is co-dominance and therefore adds to its diversity. During development, the gene is transcribed into MHC I molecules. However, some of these are broken down and react with a particular MHC I molecule. The reaction allows for the MHC I molecule to surface onto the cellular membrane and to self-identify the protein for the cytotoxic T-cell.
After translation, MHC II molecules are transported to the endosome. When a pathogen binds to the proper MHC II binding site, these molecules are then presented to T-Helper cells. In comparison, MHC I molecules interact with endogenous antigens whereas MHC II molecules interact with exogenous antigens.
Based on the passage, where is the interaction between the MHC II molecule and the particular antigen occur?
I. Endoplasmic reticulum
II. Endosome
III. Cytoplasm
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According to the passage, after the MHC II molecules are fully synthesized in the endoplasmic reticulum, they are transported to the endosome. Foreign molecules are transported into the cell where they are degraded in the endosome as well. From there, the degraded pathogen interact with the MHC II molecule.
According to the passage, after the MHC II molecules are fully synthesized in the endoplasmic reticulum, they are transported to the endosome. Foreign molecules are transported into the cell where they are degraded in the endosome as well. From there, the degraded pathogen interact with the MHC II molecule.
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Jim's body is able to produce bile salts, but unable to store it in large quantities. As a result, he cannot eat too much fat at once or it can be harmful to his digestive system. The pancreas and large intestine are not involved in bile storage.
Which of the following organs is Jim missing?
Jim's body is able to produce bile salts, but unable to store it in large quantities. As a result, he cannot eat too much fat at once or it can be harmful to his digestive system. The pancreas and large intestine are not involved in bile storage.
Which of the following organs is Jim missing?
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The role of the gall bladder is to store bile salts, but it does not produce them. Rather, bile salts are produced by the liver and transported to the gall bladder for storage.
The role of the gall bladder is to store bile salts, but it does not produce them. Rather, bile salts are produced by the liver and transported to the gall bladder for storage.
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What macromolecule is digested first by chemical means?
What macromolecule is digested first by chemical means?
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Carbohydrates begin their digestion in the mouth, where salivary amylase is produced.
Fats are emulsified by bile and digested by lipase in the small intestine. Nucleic acids are also digested in the small intestine by nucleases. Proteins begin their digestion in the stomach, where the low pH of gastric juice begins the breakdown process and pepsin begins to cleave peptide bonds. Protein digestion continues in the small intestine with other protease enzymes.
Carbohydrates begin their digestion in the mouth, where salivary amylase is produced.
Fats are emulsified by bile and digested by lipase in the small intestine. Nucleic acids are also digested in the small intestine by nucleases. Proteins begin their digestion in the stomach, where the low pH of gastric juice begins the breakdown process and pepsin begins to cleave peptide bonds. Protein digestion continues in the small intestine with other protease enzymes.
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Major histocompatibility molecules (MHC) are critical for the functioning of the immune system. These proteins are utilized allow for communication between the immune system and the cells. MHC I are utilized to show which cells are in fact part of the body and which are foreign. MHC II are utilized to show the immune system when there is an intruder.
MHC I molecules are derived from chromosome 6. On chromosome 6, there is a specific gene that encodes for the molecule. On the gene, there are 3 locus (A, B, C) which allows for variability in the binding site of the MHC I molecule. The MHC gene is co-dominance and therefore adds to its diversity. During development, the gene is transcribed into MHC I molecules. However, some of these are broken down and react with a particular MHC I molecule. The reaction allows for the MHC I molecule to surface onto the cellular membrane and to self-identify the protein for the cytotoxic T-cell.
After translation, MHC II molecules are transported to the endosome. When a pathogen binds to the proper MHC II binding site, these molecules are then presented to T-Helper cells. In comparison, MHC I molecules interact with endogenous antigens whereas MHC II molecules interact with exogenous antigens.
Based on the passage, which MHC molecule and T-cell is targeted post-organ transplant to avoid rejection of the organ?
Major histocompatibility molecules (MHC) are critical for the functioning of the immune system. These proteins are utilized allow for communication between the immune system and the cells. MHC I are utilized to show which cells are in fact part of the body and which are foreign. MHC II are utilized to show the immune system when there is an intruder.
MHC I molecules are derived from chromosome 6. On chromosome 6, there is a specific gene that encodes for the molecule. On the gene, there are 3 locus (A, B, C) which allows for variability in the binding site of the MHC I molecule. The MHC gene is co-dominance and therefore adds to its diversity. During development, the gene is transcribed into MHC I molecules. However, some of these are broken down and react with a particular MHC I molecule. The reaction allows for the MHC I molecule to surface onto the cellular membrane and to self-identify the protein for the cytotoxic T-cell.
After translation, MHC II molecules are transported to the endosome. When a pathogen binds to the proper MHC II binding site, these molecules are then presented to T-Helper cells. In comparison, MHC I molecules interact with endogenous antigens whereas MHC II molecules interact with exogenous antigens.
Based on the passage, which MHC molecule and T-cell is targeted post-organ transplant to avoid rejection of the organ?
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According to the passage, MHC I and cytotoxic t-cells are responsible for identifying the body's own protein. During organ transplant, foreign MHC I molecules are presented into the body. The host's cytotoxic T-cells will recognize these as foreign and will attack.
According to the passage, MHC I and cytotoxic t-cells are responsible for identifying the body's own protein. During organ transplant, foreign MHC I molecules are presented into the body. The host's cytotoxic T-cells will recognize these as foreign and will attack.
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Which of the following is a true statement with regard to digestive enzymes?
Which of the following is a true statement with regard to digestive enzymes?
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Amylase breaks down starch in the mouth and small intestine. Proteases are found in the stomach and small intestine. Water absorption occurs in the intestines (mostly the large intestine). Lipases break down lipids; fats are a type of lipid.
Amylase breaks down starch in the mouth and small intestine. Proteases are found in the stomach and small intestine. Water absorption occurs in the intestines (mostly the large intestine). Lipases break down lipids; fats are a type of lipid.
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The chemical reaction in the immune system that protects the body from pathogens is a result of antibodies created by which of the following?
The chemical reaction in the immune system that protects the body from pathogens is a result of antibodies created by which of the following?
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White blood cells is the correct answer here. After pathogen has entered the body, the antibodies to combat it are created by B cells that are a part of the white blood cells in the human body.
White blood cells is the correct answer here. After pathogen has entered the body, the antibodies to combat it are created by B cells that are a part of the white blood cells in the human body.
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Embryonic stem cells can go on to form any of the three germ layers (endoderm, mesoderm and ectoderm). How can they be defined?
Embryonic stem cells can go on to form any of the three germ layers (endoderm, mesoderm and ectoderm). How can they be defined?
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The ability to form any of the three germ layers is known as pluripotency. Totipotent cells, such as the zygote, are able to form an entire organism, multipotent cells are able to form any cell within the same germ layer lineage, and progenitor cells are cells closer to differentiation, often found in adult organisms.
The ability to form any of the three germ layers is known as pluripotency. Totipotent cells, such as the zygote, are able to form an entire organism, multipotent cells are able to form any cell within the same germ layer lineage, and progenitor cells are cells closer to differentiation, often found in adult organisms.
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