1.
How many chambers do amphibians' hearts have?
Correct Answer
C. Three
Explanation
Amphibians have three chambers in their hearts. This is because they have a double circulation system, where oxygenated and deoxygenated blood are partially mixed. The three chambers consist of two atria and one ventricle. The atria receive blood from the body and lungs, while the ventricle pumps the mixed blood to the body and lungs. This design allows for some separation of oxygenated and deoxygenated blood, but not as efficient as the four-chambered hearts of mammals and birds.
2.
The chambers of amphibians' hearts include
Correct Answer
C. 2 Atria and 1 ventricle
Explanation
Amphibians have a unique circulatory system that consists of two atria and one ventricle. The atria receive oxygenated blood from the lungs and deoxygenated blood from the body, while the ventricle pumps the mixed blood to the rest of the body. This arrangement allows for some separation of oxygenated and deoxygenated blood, improving the efficiency of oxygen delivery to the tissues. However, complete separation of oxygenated and deoxygenated blood is not achieved in amphibians, unlike in mammals and birds, which have four-chambered hearts.
3.
Because of a single ventricle
Correct Answer
A. There is some mixing of oxygenated and deoxygenated blood.
Explanation
The correct answer is "There is some mixing of oxygenated and deoxygenated blood." This is because in a single ventricle, the oxygenated and deoxygenated blood mix together due to the incomplete separation of the pulmonary and systemic circulations. This mixing occurs in the single ventricle and leads to a decreased oxygen saturation in the blood that is pumped out to the body.
4.
How are the Atria positioned in amphibians' hearts?
Correct Answer
D. Both atria are at the top.
Explanation
In amphibians' hearts, both atria are positioned at the top. This means that the atria are located above the ventricles. This arrangement allows for efficient blood flow, as the atria receive oxygenated blood from the lungs and then pump it into the ventricles, which will then pump the blood to the rest of the body. Having both atria at the top ensures that the oxygenated blood is directed towards the ventricles and not mixed with deoxygenated blood.
5.
Where is the ventricle located?
Correct Answer
B. At the bottom of the heart
Explanation
The ventricle is located at the bottom of the heart. The heart is divided into four chambers, with the ventricles being the two lower chambers. They are responsible for pumping blood out of the heart and into the circulatory system. The ventricles are located at the bottom of the heart because they need to generate enough force to push the blood throughout the body.
6.
The purpose of the heart in amphibians is to
Correct Answer
A. Pump blood
Explanation
The purpose of the heart in amphibians is to pump blood. The heart is a vital organ that circulates oxygenated blood throughout the body, delivering oxygen and nutrients to the cells and removing waste products. In amphibians, the heart consists of a three-chambered structure, with two atria and one ventricle. This allows for a partial separation of oxygenated and deoxygenated blood, enabling a more efficient oxygen supply to the body. The pumping action of the heart ensures a continuous flow of blood, maintaining the overall functioning of the amphibian's body.
7.
What is the color of a frog's blood?
Correct Answer
B. Red
Explanation
Frogs have red blood. This is because their blood contains a protein called hemoglobin, which carries oxygen throughout their body. Hemoglobin contains iron, which gives the blood its red color.
8.
There is less demand on the heart to deliver the oxygenated blood in amphibians' hearts...
Correct Answer
C. Because of low metabolism
Explanation
The correct answer is because of low metabolism. Amphibians have a relatively low metabolic rate compared to other animals. This means that they require less oxygen to meet their energy needs. As a result, their hearts do not need to work as hard to pump oxygenated blood throughout their bodies. This is in contrast to animals with higher metabolic rates, such as birds and mammals, which have a greater demand on their hearts to deliver oxygenated blood.
9.
To where does deoxygenated blood to return from the body?
Correct Answer
A. Right atrium
Explanation
Deoxygenated blood returns from the body to the right atrium. The right atrium receives blood from the superior and inferior vena cava, which carry deoxygenated blood from the body's tissues. From the right atrium, the blood is then pumped into the right ventricle and eventually to the lungs for oxygenation.
10.
The ventricle is subdivided by muscular columns into various compartments that
Correct Answer
D. Prevent the free mixing of the blood
Explanation
The muscular columns in the ventricle prevent the free mixing of the blood. These columns, known as trabeculae carneae, create a network of ridges and partitions within the ventricle. This structure helps to separate oxygenated and deoxygenated blood, ensuring that they do not mix together. By preventing the free mixing of the blood, the ventricle is able to efficiently pump oxygenated blood to the body and deoxygenated blood to the lungs for oxygenation.