To determine the age of an old fossil with a volcanic ash layer above it, several dating methods could be applied. One of the most reliable and commonly used dating methods is radiometric dating, specifically potassium-argon dating. This method relies on the decay of radioactive isotopes to determine the age of the sample.
In the case of potassium-argon dating, scientists look at the decay of the radioactive isotope potassium-40 into argon-40. This decay happens at a known rate, so by measuring the ratio of potassium-40 to argon-40 in the sample, the age of the fossil can be calculated. However, this method is only accurate for fossils that are millions of years old, so it is a suitable option for this situation.
Another dating method that could be used is paleomagnetism. This method relies on the fact that the Earth's magnetic field has changed over time, and certain minerals in rocks and fossils preserve a record of these changes. By analyzing the magnetic signature of the fossil, scientists can determine when it was last exposed to the Earth's magnetic field, which can help determine its age.
Overall, there are various dating methods that can be applied to determine the age of an old fossil with a volcanic ash layer above it. Radiometric dating and paleomagnetism are just two examples of these methods, but scientists may also use other methods depending on the specific circumstances of the sample.
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Am I skinny fat or just skinny
Answer:
fat
Explanation:
Answer:
You are skinny. When you are taller you will stretch out
What is the period of a wave if the wavelength is 100 m and the speed is 200 m/s?
O 0.5 s
o 25
100 s
200.000 s
Answer: 0.5 s
Explanation: speed = wavelength · frequency and period T = 1/ frequency.
Frequency = speed / wavelength = 200 m/s : 100 m = 2 s^-1 and T = 0.5 s
Summarize the path of an oxygen molecule from the nose to the bloodstream the
Answer:
The oxygen molecule passes through the wall of the alveoli and enters inside tiny blood vessels called capillaries where exchange occurs. A protein called hemoglobin in the red blood cells then carries the oxygen around your body.
Explanation:
What affects the rate of alcoholic fermentation
Answer:
The rate of fermentation is influenced by several factors like temperature, type of sugar solution, concentration of yeast and concentration of glucose.
Explanation:
Which statement would be most appropriate when thanking the Band Parents Group for a large college scholarship?
A. You guys are awesome!
B. I am totally psyched about this scholarship.
C. Your generosity shall not be unacknowledged.
D. Thank you very much for this honor,
Answer: Thank you very much for this honor,
Explanation: You should act formally when talking to people who are respected. This is the most obvious choice hence the situation.
hat are the two possibilities for Fred’s genotype?BRAIN 10 POINTS
Answer:
11%2F6_ -Amoeba Sisters Video Recap and Practice Problems.docx
Explanation:
#maxmeasabrainliestIf you bottled water from a local stream, which portion of the stream's load would eventually settle out now that it is not moving? O A. Dissolved load OB. Bed load OC. Suspended load D
If you bottled water from a local stream, the portion of the stream's load that would eventually settle out now that it is not moving is the suspended load. As a result, if you bottled water from a local stream, the portion of the stream's load that would eventually settle out now that it is not moving is the suspended load. Hence, option C is correct.
Suspended load is a term used in geology to describe small particles that are suspended within a stream's moving water and are kept from settling to the stream's bed by turbulence and currents. These particles range in size from clay to large sand grains and are held up in the water column by eddies, currents, and turbulence, which makes them appear to be in suspension. Suspended load is a crucial component of a river or stream's total load, which is the total quantity of material that a river or stream moves downstream. When the water flow decreases, the suspended load sinks to the bed and is deposited. As a result, if you bottled water from a local stream, the portion of the stream's load that would eventually settle out now that it is not moving is the suspended load. Hence, option C is correct.
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In order for geothermal energy to be produced efficiently, the geology of the area needs high subsurface _______
A. Depth
B. Pressure
C. Salinity
D. Temperature
help me please help me help me help me help me help
Answer:
D. Temperature
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anaerobic respiration allows a cell to break down carbohydrates in the absence of oxygen. identify how nad is used by animal cells during anaerobic respiration
During anaerobic respiration, animal cells use NAD+ (nicotinamide adenine dinucleotide) in a process called fermentation. In the absence of oxygen, the cells rely on fermentation to generate energy from carbohydrates.
Fermentation is a metabolic process that converts carbohydrates, such as sugars or starches, into simpler compounds, typically in the absence of oxygen. It is carried out by microorganisms like yeast, bacteria, or fungi. During fermentation, these microorganisms break down the carbohydrates into various byproducts, including alcohol, acids, or gases. Fermentation plays a crucial role in various industries, including food and beverage production.
It is widely used in the production of alcoholic beverages, such as beer, wine, and spirits. It also contributes to the formation of flavors and textures in foods like bread, cheese, yogurt, and sauerkraut. Fermentation has been employed by humans for thousands of years and has significant cultural and historical importance. It not only enhances the preservation of food but also provides unique tastes and aromas.
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Trace the path that a red blood cell would take as it travels from the following capillary beds. Include all chambers, valves, and vessels. You may use arrows between structures.
1. Right pollex to left ankle
2. spleen to left lung
3. left kidney to right frontal lobe of brain
The red blood cell starts travelling from right pollex and ends its journey at right frontal lobe of brain.
The trace the path that a red blood cell would take as it travels from the following capillary beds are below:
1. Right pollex to left ankle
• The red blood cell first travels from the capillaries in the Right pollex and enters the venule.
• From the venule, it flows through the median cubital vein to the basilic vein.
• It enters the brachial vein and travels through the axillary vein and subclavian vein.
• From the subclavian vein, it enters the left brachiocephalic vein and travels through the superior vena cava.
• Finally, the blood cell enters the right atrium, passes through the right ventricle, the pulmonary artery, lungs, pulmonary vein, left atrium, left ventricle, and aorta, and reaches the left ankle.
2. spleen to left lung
• The red blood cell first travels from the capillaries in the spleen and enters the splenic vein.• It then enters the hepatic portal vein and travels to the liver.
• From the liver, it enters the inferior vena cava.
• Finally, the blood cell enters the right atrium, passes through the right ventricle, the pulmonary artery, lungs, pulmonary vein, left atrium, left ventricle, and aorta, and reaches the left lung.
3. left kidney to right frontal lobe of brain
• The red blood cell first travels from the capillaries in the left kidney and enters the renal vein.
• It then travels through the inferior vena cava to the right atrium.
• From there, the blood cell enters the right ventricle, the pulmonary artery, lungs, pulmonary vein, left atrium, left ventricle, and aorta.
• It then travels through the brachiocephalic artery, the right subclavian artery, the right common carotid artery, and the right internal carotid artery, and reaches the right frontal lobe of the brain.
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functional sterility results when the sperm count per milliliter falls below which number?
Functional sterility results when the sperm count per milliliter falls below 20 million.
What is functional sterility?
Functional sterility is a condition that occurs in men when their sperm count per milliliter falls below a certain threshold. In men, a low sperm count is considered a problem if it is less than 15 million sperm per milliliter or 39 million sperm per ejaculate.
Functional sterility is also caused by a variety of other factors that contribute to a low sperm count. Hormonal imbalances, chronic illness, genetic defects, and some medications are examples of such factors. In some cases, radiation therapy and chemotherapy for cancer treatment may also result in functional sterility.
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what are the two effects of world war one?
Answer:
1. Loss of almost an entire generation of young men by Europe.
2. Nationalism raised in the colonial empires
Explanation:
The First World War leads to destruction of empires. Numerous new nation-states were created. United States were forced to become a world power that in turn lead to the rise of Hitler and Soviet communism.
Effects of world war one are as follows:
1. Loss of almost an entire generation of young men by Europe.
2. Nationalism raised in the colonial empires
The excretory system eliminates wastes. Identify the waste materials described. Filtered material from the blood that includes toxins like urea, salts, and even excess water. Composed of excess water, salt, and a urea that are released from glands. A mixture of undigested material, bacteria, and other materials that cannot be used by the body.
1. Urine
2. Sweat
3. Feces
Explanation: bc I said so
Urine is the filtered material from the blood that includes toxins like urea, salts, and even excess water. Sweat is composed of excess of water, salt, and a urea that are released from glands. Feces are the mixture of undigested material, bacteria, and other materials that cannot be used by the body.
What are the excretory products?Excretion is the physiological process which involves the elimination of metabolic waste products out of the body. The excretory products include amino acids, urea, uric acid, carbon dioxide, water, ammonia and other compounds.
Urine is the filtered material from the blood that include toxins such as urea, salts, and even excess water. Sweat or perspiration is composed of excess water, salt, and urea that are released from the glands. Feces are the mixture of undigested material, bacteria, and other materials that cannot be used up by the body.
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Why are flowers so important to a plant?
Answer: Flowers help purify water and also helps hold the soil in place and prevent erosion.
CREDIT: fed.us
Answer:
The primary purpose of a flower is reproduction. Since the flowers are the reproductive organs of plant, they mediate the joining of the sperm, contained within pollen, to the ovules — contained in the ovary. Pollination is the movement of pollen from the anthers to the stigma.
Explanation:
which group of genes in drosophila embryos must be mutated if the result is elimination of a significantly sized, contiguous region of segmentation?
The group of genes in Drosophila embryos must be mutated if the result is the elimination of a significantly sized, contiguous region of segmentation is gap genes.
What are gap genes?
Gap genes are a group of genes that are expressed throughout the central region of the Drosophila embryo. Gap genes, along with other segmentation genes, are responsible for establishing the boundaries between segments in the developing Drosophila embryo. Gap genes are classified into three broad categories: anterior, middle, and posterior, based on their expression patterns.
Gap genes in Drosophila are required for correct patterning of the anterior-posterior axis of the embryo. Gap genes are necessary for defining the broad regions of segmentation, which are then subdivided into smaller regions by pair-rule genes. The proper patterning of the Drosophila embryo requires the activity of gap genes.
In contrast to maternal genes, which establish the anterior-posterior axis of the embryo, gap genes define large, contiguous regions of the developing embryo and are necessary for setting up the basic body plan.
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Which of the following are possible results of mutated genes?
(Choose all that apply)
minimal effect
no effect
beneficial effect
harmful effect
Answer:
harmful effect and no effect
Explanation:
No effect: most mutated genes destroy themselves before it gets to far
Harmful effect: an example of harmful effects would be down-syndrome (where you have 3 21-chromosomes and you are only supposed to have 2)
Answer:
no effect, beneficial effect, harmful effect
Explanation:
Which of the following are possible results of mutated genes? (Choose all that apply)
no effect
beneficial effect
minimal effect
harmful effect
Beneficial mutations increase the diversity of the gene pool, which adds to the survival of the species as opposed to those that have harmful or no effect.
Took the test and these are the correct answers.
Match the following terms and definitions. 1. an electrical nerve impulse sent by nerve fibers to the central nervous system for interpretation chemoreceptors 2. neurons that detect chemicals such as those found in food effector 3. type of eyes many arthropods have; eyes that protrude outward and consist of many lenses electroreceptors 4. the structure that gives the response to an environmental change compound eyes 5. neurons that detect electrical fields action potential 6. secretion of hormones into the blood stream to affect distant processes endocrine
Answer:
1. an electrical nerve impulse sent by nerve fibers to the central nervous system for interpretation. Action potential.
2. neurons that detect chemicals such as those found in food. Chemoreceptors.
3. type of eyes many arthropods have; eyes that protrude outward and consist of many lenses. Compound eyes.
4. the structure that gives the response to an environmental change. Effector
5. neurons that detect electrical fields. Electroreceptors.
6. secretion of hormones into the blood stream to affect distant processes. Endocrine.
Explanation:
An action potential is a change in the internal charge of a cell due to depolarization. These changes allow the transmission of a message from any part of the body to the central nervous system. The central nervous system will interpret the message and will give a response.
There are different types of receptors in our bodies. Chemoreceptors are the ones that detect chemicals and produce an action potential or a neurotransmitter. These receptors respond to chemicals. Another type of receptor is the electroreceptors. They detect electrical fields and are only on the skin of aquatic animals.
Compound eyes have a large number of ommatidia. As a result, the anthropods with this type of eyes have a large view angle. In other words, every ommatidium sees an image, and the final product is a combination of all of them.
The effector is the structure that gives an answer once an affector has sent the message to the nervous system that there was a change in the environment.
There are different kinds of secretions, autocrine, paracrine, and endocrine. In the endocrine secretion, the gland secrets hormones into the bloodstream so that they can travel long distances up to their target cell, which is far from the gland.
1. an electrical nerve impulse sent by nerve fibers to the central nervous system for interpretation. Action potential
2. neurons that detect chemicals such as those found in food. Chemoreceptors
3. type of eyes many arthropods have; eyes that protrude outward and consist of many lenses. Compound eyes
4. the structure that gives the response to an environmental change. Effector
5. neurons that detect electrical fields. Electroreceptors
6. secretion of hormones into the blood stream to affect distant processes. Endocrine
The total volume of water that flows past a certain point in a given time, often expressed in thousands of cubic meters per second, is described as a stream's The total volume of water that flows past a certain point in a given time, often expressed in thousands of cubic meters per second, is described as a stream's flow
The total volume of water that flows past a certain point in a given time, often expressed in thousands of cubic meters per second, is described as a stream's flow. Accurate measurements of stream flow are crucial for many applications, such as flood forecasting, irrigation planning, and hydroelectric power generation. The flow rate of a stream is usually measured in cubic meters per second (cms), and it represents the volume of water that flows past a certain point per second.
The stream's flow may vary significantly depending on the season, precipitation, and other factors. Some streams may be entirely dry in summer, while others may carry several thousand cubic meters of water per second.The total volume of water that flows past a certain point in a given time can be expressed as a rate in units of volume per time, such as cubic meters per second or thousands of cubic meters per second. For example, a stream's flow rate of 5000 cubic meters per second means that 5000 cubic meters of water flow past a given point on the stream every second. In stream flow rate is the total volume of water that flows past a certain point in a given time, often expressed in thousands of cubic meters per second. It can be calculated as the product of the stream's cross-sectional area and its average velocity. The flow rate of a stream can vary significantly depending on precipitation, season, and other factors, and it is an important consideration for the management of water resources. Accurate measurements of stream flow are crucial for many applications, such as flood forecasting, irrigation planning, and hydroelectric power generation.
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Inside a human stomach, hydrochloric acid is important in digestion. Which reason best explains why the enzymes found in other parts
of the body would not function well in the stomach?
a. The temperature is too high
b. There is not enough water
C. The pH is too acidic
d. There are not enough substrates
Answer:
C. The pH is too acidic
Explanation:
Many acids and bases in living things are secreted to provide the proper pH for enzymes to work properly. Enzymes are biological catalysts, such as pepsin, which is needed to digest protein in the stomach and requires an acidic environment.
A person's debt-to-income ratio describes:
A. how much money a person can borrow from a bank at any given
time.
B. how frequently a person has to make payments on a significant
debt.
C. how much the person has borrowed compared to how much he or
she earns.
D. how often the person's credit score changes based on increasing
levels of debt.
Answer:
A. how much money a person can borrow from a bank at any given
time.
Explanation:
The debt-to-income (DTI) ratio measures the amount of income a person or organization generates in order to service a debt.
A doctor has diagnosed a patient with atherosclerosis. When listening to the blood flow through
might the disease diagnosis affect the sound being detected by the physician?
The blood flow sounds different because the blood is flowing through
vessels with a narrowing of the inner walls of coronary arteries due to
buildup of fatty materials.
The blood flow sounds different because there is a widening of inner walls
of blood vessels due to a high salt diet.
B)
The blood flow sounds different because the walls of the heart have been
stretched due to a heart attack
D
The blood flow sounds different because there is an increased circulation
to the heart.
Answer:
The blood flow sounds different because the blood is flowing through vessels with a narrowing of the inner walls of coronary arteries due to buildup of fatty materials.
Explanation: Atherosclerosis is characterized by cholesterol deposits in the walls of the arteries. This can be hereditary but is often impacted by increased fatty diets.
The disease diagnosis affect the sound being detected by the physician is when the blood flow sounds different. hence, the first option is correct.
Impact on the sound that being detected:Since the patient was diagnosed with atherosclerosis so here the flow of the blood should be sounded different since the blood is flowing via the vessels that have the narrow inner walls because of fatty materials.
Also, Atherosclerosis should be contributed by the cholesterol that is deposited into arteries walls.
hence, the first option is correct.
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7. Compare and contrast the way carbon is used in respiration and photosynthesis
.
8. How does carbon get into the ocean?
9. What is carbon used for when it is in the ocean?
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.how does contraction of a single muscle cell, which would cause tension on the surrounding endomysium, ultimately cause tension on the tendon of the muscle?
When a single muscle cell contracts, the causes tension on the surrounding endomysium, ultimately causing tension on the tendon of the muscle to be transferred to the surrounding endomysium.
What is a contraction?Contraction is the act of pulling or tightening a muscle through the movement of the muscle fibres. This movement generates tension, which is transmitted through the endomysium to the tendon of the muscle.
A single muscle cell is the fundamental unit of muscle contraction. The contraction of these cells results in a number of biochemical and biophysical changes within the cells, culminating in muscle tension. The tension is transferred to the surrounding endomysium, which is a thin layer of connective tissue surrounding each muscle fiber. When tension is applied to the endomysium, it transfers the force to the perimysium, which is a thicker connective tissue layer that surrounds bundles of muscle fibers.
Finally, the tension reaches the epimysium, which is a dense layer of connective tissue that surrounds the entire muscle. The epimysium is continuous with the tendon, which is a tough band of connective tissue that connects the muscle to the bone. Therefore, the contraction of a single muscle cell causes tension in the tendon of the muscle.
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How do species evolve?
Answer:
Natural selection.
Explanation:
Animals mate with different animals creating a species with different genes that helps their kin live longer or stronger.
4 A population of tree-climbing lizard lives on one bank of a large river.
The other bank of the
river is a treeless prairie. During a flood, 40
lizards were transferred to the prairie side
of the river. After 200
generations, this transferred population of lizard lost the ability to
climb.
Which mechanism is MOST likely responsible for this loss of function
within the transferred
population?
natural selection
genetic drift
gene flow
mutation
Answer:
Genetic Drift, it is a textbook example of genetic drift.
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If a mutation has no effect on fitness, it may stay in the gene pool indefinitely.
TRUE/FALSE
The given statement "If a mutation has no effect on fitness, it may stay in the gene pool indefinitely" is true because If a mutation has no effect on fitness, meaning it neither enhances nor reduces an organism's ability to survive and reproduce.
It is considered neutral in terms of natural selection. In this case, the mutation can persist in the gene pool indefinitely. Since natural selection acts on traits that affect an organism's fitness, mutations that have no impact on fitness are not subject to selective pressures. As a result, these neutral mutations can accumulate and persist in a population without being eliminated by natural selection.
Over time, the frequency of these neutral mutations may fluctuate due to genetic drift, migration, or other factors, but they can remain in the gene pool over generations. It's important to note that even though a neutral mutation may persist, it may still be lost or go to fixation in a population due to random chance or other evolutionary forces.
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chromosome 7 has a gene named foxp2. if this gene were spliced into non-human animals, would they be able to produce speech?
Chromosome 7 contains the gene FOXP2 which is involved in speech and language development. The FOXP2 gene is important in the development of certain parts of the brain that are necessary for speech and language. However, simply splicing the FOXP2 gene into non-human animals would not be sufficient for them to produce speech.
Speech and language are complex behaviors that involve a variety of factors including brain structure, neural connections, and muscle control. While the Chromosome 7 consisting FOXP2 gene is involved in some aspects of language development, it is not the only gene involved, and it cannot by itself give animals the ability to produce speech. Moreover, the human version of the FOXP2 gene differs from that of other animals in important ways. Mutations in the FOXP2 gene in humans have been associated with language disorders, and studies have shown that the gene plays a role in the development of certain brain regions involved in speech and language. Therefore, while splicing the FOXP2 gene into non-human animals might lead to some changes in brain development, it would not be sufficient to give them the ability to produce speech as seen in humans.
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tadpoles must undergo a major metamorphosis to become frogs. this change includes reabsorption of the tail, growth of limbs, calcification of the skeleton, increase in rhodopsin in the eye, development of lungs, change in hemoglobin structure, and reformation of the gut from the long gut of an herbivore to the short gut of a carnivore. amazingly, all of these changes are induced by triiodothyronine. what is the most likely explanation for such a wide array of effects of thyroxine?some tissues have membrane receptors for triiodothyronine, while other tissues have triiodothyronine receptors within the nucleus.different releasing hormones release triiodothyronine to different tissues.there are many different forms of triiodothyronine, each specific to a different tissue.different tissues have triiodothyronine receptors that activate different signal transduction pathways.
The hormone triiodothyronine (T3) plays a crucial role in the metamorphosis of tadpoles into frogs, triggering various transformative processes such as tail reabsorption, limb growth, skeletal calcification, and organ development.
Triiodothyronine (T3) is a hormone that regulates the body's metabolism. Tadpoles undergo a major metamorphosis to become frogs, which involves several changes, such as reabsorption of the tail, growth of limbs, calcification of the skeleton, increase in rhodopsin in the eye, development of lungs, change in hemoglobin structure, and reformation of the gut from the long gut of an herbivore to the short gut of a carnivore.
Interestingly, all of these changes are induced by triiodothyronine.
Different tissues have triiodothyronine receptors that activate different signal transduction pathways is the most likely explanation for such a wide array of effects of thyroxine.T3 receptor, a member of the nuclear hormone receptor superfamily, is present in the cell nucleus of many tissues, including those in the nervous system, liver, kidney, and the cardiovascular system.
The receptor is a transcription factor that binds to DNA in the cell nucleus, where it activates or represses gene expression. The T3 receptor regulates the transcription of target genes that are critical for controlling development, growth, differentiation, and metabolism in various tissues.
T3 controls a wide range of physiological processes by regulating gene expression, and the effects of T3 are tissue-specific.
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help me help plssss its 8th grade
Answer:
it is not readen can you please take a picture again
Select the correct statement about the three-chambered hearts of amphibians and nonbird reptiles. A scheme of blood circulation of reptiles except for birds. The reptiles have a three-chambered heart that consists of two atria and one ventricle with an incomplete septum. There are two circuits: pulmonary and systemic. In the pulmonary circuit, the blood from the right ventricle is pumped in to lung capillaries and returned to the left atria. In the systemic circuit, the blood is pumped from the left ventricle to the systemic capillaries via the left systemic aorta and is then returned to the right atria. There is also one vessel going from the right ventricle to the aorta right before it branches to smaller arteries. This vessel carries mixed blood. All blood on the right side of the circuits is venous and all blood on the left side is arterial. Select the correct statement about the three-chambered hearts of amphibians and nonbird reptiles. The three-chambered hearts of amphibians and nonbird reptiles are facultative, allowing variation in blood flow through the heart. The three-chambered heart is inferior to the four-chambered hearts of birds and mammals, limiting the evolutionary success of amphibians and nonbird reptiles. Pulmonary and systemic blood fully mixes in the ventricle of a three-chambered heart.
Answer:
The three-chambered hearts of amphibians and nonbird reptiles are facultative, allowing variation in blood flow through the heart.
Explanation:
In Anatomy, cardiac cycle can be defined as a complete heartbeat of the human heart which comprises of sequential alternating contraction and relaxation of the atria and ventricles, therefore causing blood to flow unidirectionally (one direction) throughout the human body.
Generally, the cardiac cycle occurs in two (2) stages;
I. Diastole : in this stage, the ventricles is relaxed and would be filled with blood.
II. Systole: at this stage, the muscles contracts and thus, allow blood to be pushed through the atria.
All amphibians and reptiles except for crocodiles (having four-chambered heart) have three-chambered hearts, which typically comprises of a partially divided ventricle and two atria.
Hence, the correct statement about the three-chambered hearts of amphibians and nonbird reptiles is that, the three-chambered hearts of amphibians and nonbird reptiles are facultative, allowing variation in blood flow through the heart due to the partially divided ventricle.