Answer: The glucose extracted is stored in the liver as glycogen, which is made available to the body as needed. In this case, the liver cells function as a fuel reservoir.
Explanation:
Glycogen is the available reserve of glucose to supply tissues with a source of energy and is found mainly in the liver, this is considered a source of glucose that can be used throughout the body. The main area of daily glucose consumption is the brain, via the aerobic route. The biggest part of the remaining energy is used by red blood cells, skeletal and cardiac muscles. The body obtains glucose through diet or gluconeogenesis pathway. The glucose obtained from these two primary sources remain soluble in body fluids or are stored in a polymeric form called glycogen. Glycogen is considered the main form of glucose deposition and is found mainly in the liver and muscle.
Once processed in the liver, glucose either circulates in the body supplying energy, gets stored as glycogen for short-term energy reserves, or reformed into triglycerides and fatty acids for long-term storage. If needed, the liver can also produce glucose through the process of gluconeogenesis. These processes are all key parts of carbohydrate metabolism.
Explanation:After glucose has been processed in the liver, it has multiple fates depending on the body's needs. It can remain in the bloodstream, providing energy in the form of ATP through a process known as glycolysis. This process, occurring in body cells, involves a series of reactions that transfer the energy in glucose to ADP to form ATP, with the product being pyruvate.
If the body has more glucose than is immediately needed, this excess glucose can be stored in the liver as glycogen or be converted into triglycerides and fatty acids for long-term storage. Should the body need more glucose, such as during fasting, the liver is capable of gluconeogenesis, a process where it produces more glucose.
The role and fate of glucose in the body is part of the larger process of carbohydrate metabolism, where complex carbohydrates are broken down into simple sugars and ultimately used for energy production.
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The muscle that serves as the prime mover during a movement is called the
Answer:
Agonist
Explanation:
The muscle that serves as a prime mover during a movement is called "agonist". Agonist refer to the leader muscles that contract and cause the movement.
For example, the deltoid muscle is the prime mover or agonist. Contraction of deltoid muscle causes abduction of the arm. An agonist for one type of movement may serve as antagonist or fixator for some other movement.
Which of the following vitamins is used to construct the coenzymes NADH and NADPH?
a. Riboflavin
b. Panthothenic acid
c. Vitamin B12
d. Niacin
Answer: d. Niacin
Explanation:
Many vitamins are parts of coenzymes. In numerous oxidation-reduction reactions that are catalyzed by enzymes, the electrons pass in pairs from the active site of the enzyme to a coenzyme that serves as the electron acceptor. Vitamin B3 or Niacin is used to construct the coenzymes NADH and NADPH, their sources for human ingestion are liver, lean meats, and grains. Its deficiency in consumption leads to Pellagra, inflammation of nerves and mental disorders.
Final answer:
D) Niacin (Vitamin B3) is the vitamin used to construct the coenzymes NADH and NADPH, which are essential for metabolic processes such as energy production.
Explanation:
The vitamin that is used to construct the coenzymes NADH and NADPH is niacin (B3). These coenzymes play a crucial role in various metabolic processes, including energy production and synthesis of fatty acids and steroids. Niacin is therefore essential for the conversion of food into energy and for maintaining healthy cells.
It's important to note that riboflavin (B2) is involved in the formation of another coenzyme, flavin adenine dinucleotide (FAD), which is also used in cellular respiration but is different from NADH and NADPH.
Bacteria are grown in 15N (heavy) medium and then transferred to 14N (light) medium and are allowed to replicate for 1 generation. The DNA is subsequently isolated and centrifuged in a CsCl2 gradient to yield what type of gradient band(s)?
Answer:
The intermediate density band is observed.
Explanation:
Messelson and Sthal's explained the model of semi conservative nature of DNA replication. According to this model, the newly synthesized DNA molecule contains one newly synthesized strand and one parental strand.
Firstly, bacteria grown in 15N media is transferred to 14N media. The isolated DNA is centrifuged and intermediate density DNA band is observed that contains one strand of 15N (parental strand) and one strand of 14N (newly synthesized strand).
Bacteria grown in a 15N medium and then transferred to a 14N medium for one generation produce DNA that, when centrifuged in a CsCl2 gradient, forms a band at an intermediate position between DNA formed in 15N and 14N. This supports the semi-conservative replication model of DNA.
Explanation:The experiment you're referring to was conducted by Matthew Meselson and Franklin Stahl. They used E. coli and grew it initially in a heavy nitrogen medium (15N). Afterward, these bacteria were transferred into a 14N (lighter nitrogen) medium where they were grown for one generation.
During the replication in the 14N medium, DNA from the bacteria was isolated and centrifuged in a cesium chloride (CsCl2) gradient. The result was, that a single band was observed which settled at an intermediate position between DNA formed in 15N and 14N. This finding supports a semi-conservative replication model where each new DNA molecule consists of one old and one new strand.
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36. In the Calvin cycle, where plants use the energy from photosynthesis to synthesize glucose, what enzyme is need for carbon fixation?
a. Rubisco
b. Crisco
c. Formaldehyde
d. Lactase
Answer: a. Rubisco
Explanation:
Photosynthesis is a way of making organic molecules from carbon dioxide (CO2). To build organic molecules, cells use raw materials provided by the light reactions. 1,5-bisphosphate carboxylase, also known as Rubisco, is the enzyme needed for carbon fixation during the Calvin cycle. This enzyme is found in the stromal space of the chloroplast. It acts by adding CO2 to the 5-carbon sugar ribulose 1,5-bisphosphate forming 2 molecules of 3-phosphoglycerate.
What is a ductless gland?
3. Mammals lack the enzymes for the net conversion of acetyl-CoA into oxaloacetate or any other citric acid cycle intermediate, but if oxaloacetate (or some other citric acid cycle intermediate) is drawn off for biosynthesis, it must be replenished. How is oxaloacetate replenished? Under what cellular conditions would this enzymatic step be favored?
Answer:
-Oxaloacetate is replenished by enzyme pyruvate carboxylase.
-This enzymatic reaction is favored when there is an increased demand of energy required by the cell.
Explanation:
Citric acid cycle is a major pathway for the ATP production. Oxaloacetate plays an important role in citric acid cycle as it starts with transfer of acetyl group of acetyl CoA to oxaloacetate with formation of citrate.
As mammals lack enzyme to convert acetyl-CoA into oxaloacetate, in mammals oxaloacetate is replenished by enzyme pyruvate carboxylase that performs carboxylation of pyruvate to form oxaloacetate.
Activity of this enzymatic reaction increases by high energy demand of cell, and increased level of acetyl CoA as it shows increased demand of oxaloacetate to perform citric acid cycle for energy production.
1. In the carbon cycle, the role of plants is to
Answer:
Release Oxygen and absorb Carbos dioxide from the air
True or False. The anterior pituitary gland is connected to the hypothalamus through capillaries that form the hypothalamus pituitary portal vasculature.
Answer:
True.
Explanation:
The anterior pituitary gland is connected to the hypothalamus through capillaries that form the hypothalamus pituitary portal vasculature.
Compare sympathetic vs parasympathetic nervous system
An understanding of how stress affects our resistance to disease is the central focus of the field of
Answer:
Psychoneuroimmunology
Explanation:
Psychoneuroimmunology also known as psychoneuroendocrinoimmunology, is a field of science in which scientists study about the effect of nervous and psychological processes on the immune system of man.
The latest scientific studies strongly support the fact that many health ailments like gastro-intestinal diseases, cancers, HIV, eczema, Asthma are strongly linked with the mental health of an individual. A positive outlook and a less stressful mind has clearly more healing effects towards the body or in other words a peaceful and positive mind exhibit more resistance towards many diseases.
All such cases are studied in the field of Psychoneuroimmunology and latest researches and cases are supporting above mentioned facts.
Hope it helps!
Explain why there would be more errors in dna replication if thymine was sometimes able to form bonds with cytosine. PLEASE HELP
Answer:
DNA contains four base pairs: adenine, thymine, cytosine and guanine. Adenine forms bond with thymine, its a double bond, and cytosine forms triple bond with guanine.
Cytosine in natural process does not forms bond with thymine, but if it happen then many errors could occur in replication. As DNA is the basic material of cell and all genetic information lies in it, a single mutation can lead to fatal disorders, and when cytosine forms bond with thymine instead of guanine then the backbone of DNA would be distorted, RNA being formed from this DNA would also be have errors that would result in mutated proteins that can cause serious illness and destroy many natural processes.
You are studying a protein called myprotein in the cytosol. You want to see if another protein called, otherprotein, is required for folding. You isolate the cytosolic fraction using salt precipitation. You want to perform an experiment to find if otherprotein binds and interacts with mylittleprotein. Which assay would be best to perform first?
a. SDS PAGE to see the banding pattern showing all the proteins that interact
b. Immunopreciptation, because this will allow us to pull down proteins that interact
c. Size chromatography, because chances are the proteins that interact are the same size
d. Affinity Chromatography, because we know that it binds other proteins
Answer:
size chromatography, because chance are the protein that interact are the same size
Indicate whether each of the following reactions is anabolic or catabolic by circling the appropriate word: Reaction Type of Reaction 1. Glucose + glucose → glycogen
Answer:
The reaction of Glucose + Glucose → Glycogen is called glycogenesis and is an anabolic reaction.
Explanation:
Metabolic reactions can be anabolic or catabolic. Anabolic reactions are those where small molecules are joined to form a larger molecule; and the use energy. On the other hand, catabolic reactions are those where large molecules are broken in smaller molecules; and they release energy.
Glucose molecules are smaller than Glycogen. For this reason, the metabolic reaction of Glucose + Glucose → Glycogen is an anabolic reaction called glycogenesis.
glycogenesis
Two types of metabolic reactions take place in the cell: 'building up' (anabolism) and 'breaking down' (catabolism).
Anabolic reactions use up energy. They are endergonic. In an anabolic reaction small molecules join to make larger ones. For example, the following condensation reactions that occur in cells are anabolic:
Sympathetic nervous system vs parasympathetic nervous system
Answer:
Differences between Sympathetic and Parasympathetic
1. Anatomical: The location of preganglionic neurons of the autonomic ganglia and the extension of preganglionic and postganglionic fibers are different in these two systems;
2. Pharmacological: In the Sympathetic system we have the presence of Cholinergic fibers (Ach) and in the Parasympathetic system we have the presence of Noradrenergic fibers (NE);
3. Physiological: They act antagonistically, they rarely work harmoniously synergistically in coordinating visceral activity (balance)
The sympathetic nervous system readies the body for action, while the parasympathetic nervous system helps the body relax and recover. Sympathetic and parasympathetic divisions of the autonomic nervous system work in opposition to each other, regulating different bodily functions.
The sympathetic nervous system prepares the body for 'fight or flight,' whereas the parasympathetic nervous system allows the body to 'rest and digest.' Sympathetic neurons release norepinephrine onto target organs; parasympathetic neurons release acetylcholine. Activation of the sympathetic nervous system increases heart rate and blood pressure and decreases digestion and blood flow to the skin. Activation of the parasympathetic nervous system decreases heart rate and blood pressure and increases digestion and blood flow to the skin.
True or False: Smooth muscle is under control of the autonomic nervous system.
Answer:
True.
Explanation:
Autonomic nervous system is the division of peripheral nervous system. Autonomic nervous system control the involuntary actions of body like digestion, respiration, urination and heart rate.
Autonomic nervous system supplies the glands and smooth muscle and regulates the function of the internal organs. Hence, the smooth muscle is controlled by autonomic nervous system.
Thus, the given statement is true.
Which condition involves an uninjured body part experiencing pain as the result of injury to another part of the body?
Select one:
a. sensory adaptation
b. referred pain
c. receptor potential
d. interceptors
Answer:
Referred pain
Explanation:
Referred pain may be defined as the pain perceived at differnet location of body other than the individual pain location.
Referred pain depends upon the intensity and duration of the pain. Refereed pain is generally generated by the potent mechanism of temporal summation. Referred pain is the condition of the body in which the uninjured body part experiences pain due to the injury of another body part.
Thus, the correct answer is option (b).
The apical ends of intestinal cells face the intestinal channel and have long processes that facilitate the absorption of nutrients. What is the name of these processes and what cytoskeletal element forms their internal skeleton?
Answer:
microvilli, actin filaments
Explanation:
The apical ends of intestinal cells face the intestinal channel and have long processes that facilitate the absorption of nutrients. the name of these processes is microvilli and actin filaments from the cytoskeletal element forms their internal skeleton.
Acid chyme produced by the stomach is neutralized in the intestine by what?
Answer: Sodium bicarbonate produced by the Pancreas.
Explanation:
The mixture of partially digested food and gastric juice is called chyme. Chyme leaves the stomach through the pyloric sphincter to enter the small intestine. This is where all terminal digestion of carbohydrates, lipids, and proteins occurs, and where the products of digestions—amino acids, glucose, and so on—are absorbed into the blood. The first 25 centimeters is the duodenum; the remainder of the small intestine is divided into the jejunum and the ileum. The duodenum receives acidic chyme from the stomach, digestive enzymes, and bicarbonate from the pancreas, and bile from the liver and gallbladder. The pancreatic juice enzymes digest larger food molecules into smaller fragments.
Acid chyme from the stomach is neutralized in the intestine by bicarbonate, which is released by the pancreas. This happens in the duodenum, the first part of the small intestine.
Explanation:The acid chyme produced by the stomach is neutralized in the intestine by a substance called bicarbonate. Bicarbonate is released by the pancreas and works to neutralize the acidity of the chyme which is essential for the enzymes in the intestine to function properly. This process takes place in the duodenum, the first section of the small intestine, right after the stomach.
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Chymotrypsin
a. is secreted by the pancreatic acinar cells
b. digests proteins into peptides
c. works in the small intestine
d. all of the above
Answer: d. all of the above
Explanation:
Chymotrypsin is produced by the Pancreas and has the function of digesting proteins.It consists of three polypeptide chains connected by two inter-chain disulfide bridges. Chymotrypsin exerts an important biological function which is the hydrolysis of proteins in the small intestine. The cleavage of peptide bonds is selective, occurring only on the carboxyl side of aromatic side chains of tyrosine, tryptophan and phenylalanine, and large hydrophobic radicals such as methionine. Chymotrypsin also hydrolyzes ester
Briefly differentiate "White Matter" & "Grey Matter".
Answer:
The CNS, or central nervous system is comprised of neurons, the cell units that form it. These cells, in turn, are formed by their cell bodies, the dendrites on them and the terminal ends of the axons, which are like the connectors, or roadways, for neurons. When viewed on a microscope, brain tissue, particularly, looks stained with two different colors: grey, or pinkisk, for the grey matter, and whiter for the white matter, which are the axons. This is basically why the two are called grey matter and white matter of the CNS.
So one difference between these two matters is the color they display when viewed. The second is the parts of the neuron that form the two; while the white matter is formed from the neuronal axons, the grey matter is formed by the dendrites, cell bodies and axonal terminals. A third differentiation is that most synaptic activity takes place in the grey matter, while most conduction of information from the cell bodies is performed by the axons.
White matter, consisting of myelinated axons, contributes to the CNS's communication network, while gray matter contains neuronal cell bodies and is involved in processing. Their composition difference, particularly the presence of fatty myelin in white matter, makes them distinguishable on MRI images. Brain development continues through adolescence, affecting the gray to white matter ratio.
Explanation:White matter and gray matter are two distinct types of nervous tissue found in the central nervous system (CNS). Gray matter consists primarily of neuronal cell bodies, dendrites, and non-myelinated axons, which give it a grayish appearance and is primarily involved in processing and cognition. It makes up the outer cortex of the brain. White matter, on the other hand, is made up of myelinated axons that form tracts and facilitate rapid communication between different gray matter areas.
The fatty myelin sheath around the axons gives white matter its characteristic lighter color. This difference can be easily identified in MRI images due to the contrast provided by the fatty tissue and water content. While gray matter is associated with the cortex and processing centers, white matter acts as a network of conduits providing connectivity and communication across different brain regions.
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5. Discuss about the narrow sense conception of cytoskeleton and the classification and function of each components
Answer:
The narrow sense conception of cytoskeleton is introduced to protein fibres. These fibres are present inside the eukaryotic cells. This concept refers to the study of cytoskeleton. Cytoskeleton maintains the cell shape. Cytoskeleton have two components. These are nuclear skeleton and cytoplasmic skeleton.
Nuclear skeleton consist of core layer, nuclear matrix and chromosomal skeleton. Cytoplasmic skeleton comprises of microtubules, microfilaments and intermediate filaments.
Explanation:
The narrow sense conception of cytoskeleton is related to protein fibre structure in eukaryotic cells. The cytoskeleton system comprises of nucleus skeleton and cytoplasmic skeleton.
The nucleus skeleton consist of chromosomal skeleton, nuclear matrix and core layer.
Nuclear Matrix: It organize DNA into the cell with the help of nuclear lamina.
Core layer: It is the inner layer which connects nuclear matrix and outside fibres. It forms a grid structure between nucleus and cytoplasm.
Chromosome Skeleton: It is involved in packaging of chromosomes.
The cytoplasmic filaments consist of intermediate filament, microtubules and microfilaments.
Intermediate Filaments: It provides mechanical support to plasma membrane.
Microtubules: It maintains shape of the cell. It is involved cell wall formation.
Microfilaments: It is involved in myofibrils formation, acrosomal reaction and cytoplamic splitting like processes.
What is the perimesencephalic subarachnoid hemorrhage?
Answer: Perimesencephalic haemorrhage (PSH) is defined as confined bleeding in the cisterns around the mesencephalon, called: the cerebral aqueduct, tegmentum, the tectum, and the cerebral peduncles.
Explanation:
PSH has a probable incidence in patients with negative angiographies of around 50% to 75%. It is a pathology with no predominant age range, reported in all ages in the literature, including childhood. By definition, the condition corresponds to a tomographic finding of blood in the interpeduncular cistern that may extend to the other portions of the mesencephalon. This pathogenesis has not yet been completely clarified, but it is believed to come from a nonarterial source, assuming venous or capillary origin.
Which muscle have their insertion on the calcaneus?
Answer:
Gastrocnemius, plantaris and soleus muscle have insertion on calcaneus.
Explanation:
Calcaneus is also known as heel bone. This is the tarsus bone of the foot and other animals consist it as a point of hook.
Three muscles involved in the insertion of calcaneus are Gastrocnemius muscle, plantaris muscle and soleus muscle. These muscles are present in the posterior compartment of leg and helps in running, jumping and walking.
Describe difference between dehydration reaction and hydrolysis. How do these reactions relate to macromolecules?
Answer:
Dehydration reaction includes removal of water molecule from compounds to facilitate formation of bonds between them while hydrolysis reactions break the compounds by breaking the bonds.
Dehydration reactions form the complex macromolecules while hydrolysis reactions break them down into the simpler elements.
Explanation:
During dehydration reactions, removal of a water molecule from two compounds leads to the formation of a covalent bond between them. These reactions are mainly part of anabolic pathways. Two amino acids are joined together by peptide bond and a water molecule is released during the reaction.
Hydrolysis reactions are the opposite of dehydration reactions and are involved in catabolic pathways of macromolecules. The peptide bonds between amino acids are broken down by hydrolysis.
Dehydration reactions involve the formation of new bonds, while hydrolysis reactions break bonds and release energy. Each macromolecule is broken down by a specific enzyme.
Explanation:Dehydration and hydrolysis reactions are catalyzed, or "sped up," by specific enzymes; dehydration reactions involve the formation of new bonds, requiring energy, while hydrolysis reactions break bonds and release energy. These reactions are similar for most macromolecules, but each monomer and polymer reaction is specific for its class. For example, in our bodies, food is hydrolyzed, or broken down, into smaller molecules by catalytic enzymes in the digestive system. This allows for easy absorption of nutrients by cells in the intestine. Each macromolecule is broken down by a specific enzyme. For instance, carbohydrates are broken down by amylase, sucrase, lactase, or maltase. Proteins are broken down by the enzymes pepsin and peptidase and by hydrochloric acid. Lipids are broken down by lipases. The breakdown of these macromolecules provides energy for cellular activities.
Which of the following processes would manufacture glucose and other sugars from non-carbohydrate sources?
(a) Glycogenolysis
(b) Glycogenesis
(c) Gluconeogenesis
(d) Beta oxidation
Answer: (c) Gluconeogenesis
Explanation:
Gluconeogenesis (“new formation of glucose”) uses amino acids and lactic acid obtained from muscle proteins to convert into glucose. The glucocorticoids stimulate the liver to produce the enzymes needed for gluconeogenesis, the conversion of amino acids into glucose. This creation of glucose from protein is particularly important during very long periods of fasting or exercise when blood glucose levels might otherwise become dangerously low.
The newly-discovered organism Yawle nhoj, has a diploid chromosome number of 56. Suppose that one of the chromosome pairs fails to disjoin properly during Meiosis I. How many chromosomes will be present in each of the four gametes that result from that meiosis? Assume meiosis II is normal.
Answer:
The correct answer will be 2 gametes with 29 chromosomes and 2 gametes with 27 chromosomes will be formed.
Explanation:
Meiosis is a type of cell division which produces four daughter cells. Chromosomes separate or the disjunction of chromosomes takes place during anaphase I and anaphase II of meiosis I and II respectively.
If a chromosome fails to disjoin at meiosis I this will result in the production of four gametes with an unequal number of chromosomes. Out of four gametes, 2 gametes produced will be trisomic gametes that are with one additional copy of chromosome and 2 gametes will be monosomic with one less number of chromosome. It means the trisomic gametes will have 29 chromosomes while 2 monosomic gametes will have 27 chromosomes.
Thus, 2 gametes with 29 chromosomes and 2 gametes with 27 chromosomes will be formed is the correct answer.
Some digestive products, such as water and electrolytes, will be absorbed by diffusion. They diffuse from an area of ____________ concentration in the intestinal lumen to an area of ____________ concentration in the cell.
Answer: Higher concentration; Lower concentration.
Explanation: The food that we eat undergoes digestion and breaks down into smaller components.
These small components of the food needs to be absorbed first by the process of diffusion.
The water molecules along with the electrolytes are absorbed from an area of its higher concentration in the lumen is transported to area where its concentration is very low.
Hence, the correct answer is diffusion, which is responsible for the transportation of products from one place (higher concentration) to another parts (lower concentration)in the body.
Digestive products like water and electrolytes are absorbed by diffusion, moving from an area of higher concentration in the intestinal lumen to an area of lower concentration in the cells. This happens both in the context of water and electrolytes and is guided by concentration gradients. The small intestine is the primary site for these absorption processes.
Explanation:Some digestive products, such as water and electrolytes, will be absorbed by diffusion. They diffuse from an area of higher concentration in the intestinal lumen to an area of lower concentration in the cell. This is a process driven by concentration gradients. The small intestine absorbs most of these substances with the aid of its absorptive cells and specialized structures like the microvilli.
For example, each day, about nine liters of fluid, containing water and electrolytes, enter the small intestine from ingested food, beverages, and GI secretions. About 90% of this water is absorbed in the small intestine, moving from an area of higher concentration in the chyme (the digestive substance in the lumen) to an area of lower concentration in the epithelial cells of the intestine. Similarly, electrolytes dissociate into ions in water and most of them are absorbed via active transport mechanisms throughout the small intestine.
Water movement in the body is facilitated by osmosis, a specialized form of diffusion. Water flows from regions of higher concentration to regions of lower concentration along an osmotic gradient across semi-permeable membranes, helping maintain an appropriate balance of solutes inside and outside of cells to ensure their proper function.
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1. Which of the following gene is responsible for an amino acid synthesis in YAC vector?
CEN
URA3
ARS
TRP1
Answer:
option a
Explanation:
cen
Junction between a motor neuron and a skeletal muscle fiber 1) sarcoplasmic reticulum 2) junction 3) motor end plate 4) axon terminal
Answer:
Junction.
Explanation:
Junction or neuromuscular junction may be defined as a type of chemical synapse and the site where motor neuron transmit information to the muscle fibers and causes the muscle contraction.
The junction is formed by the contact between the skeletal muscle fibre and motor neuron. The mutation in neuromuscular junction may cause autosomal disorders in an individual.
Hence, the correct answer is option (2).
Where is the first electrical wave in the heart initiated?
Answer:
Sinoatrial Node
Explanation:
The sinoatrial node is like the natural pacemaker of the heart because it controls the heart beat or in other words, the cardiac rhythm. The sinoatrial node is found on the right atrium and it sends signals to both atria and then they contract. The signal is then carried to the atrioventricular node which spreads the signal to the ventricles and then the ventricles contract. The contractionof the ventricle is the pumping action of the heart.