Answer: Option D
Explanation:
Once the pathogen enters the body, it starts dividing and after a certain period of time the patients experience some sign and symptoms of illness.
The prodromal period occurs just after the incubation period. In this phase the pathogen keeps on dividing and the host begins to experience general symptoms and signs of illness.
This is a result of the activation of immune system of the body which results in the swelling, pain, soreness.
<span>Answer
1. electrical signal travels toward the heart
2. signal by the nodes in the atrium</span>
3. the atria contract<span>
</span>4. signal received by the atrioventricular node
5. signal transferred to the ventricles
6. the ventricles contract
Heart has a pacemaker that will continually send a signal. The primary site of the pacemaker is at the sinoatrial node, on the top right atrium. This node will send a signal to atria (which will cause it to contract) and to the atrioventricular node.
Atrioventricular node located between atrium and ventricle. It will send the signal to the ventricle(by the bundle of his) and cause it to contract.
study suggests that photosynthetic eukaryotes may have emerged around 1.9 billion years ago in freshwater habitats. Eukaryotes are thought to have evolved the capacity for photosynthesis through a process called endosymbiosis, in which a protist host encapsulated a photosynthetic cyanobacterium.
Photosynthetic bacteria changed the Earth's atmosphere
I believe the correct answer would be the last option. After Frida stops exercising, it caused her body to be lack of oxygen that is why she breathes heavily to take in more oxygen from air. Also, with this, lactate is being transported to the liver. The lactate is a result of the anaerobic respiration.