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.
Answer;
B. Water purification programs
Explanation;
The goal of hygiene promotion is to help people to understand and develop good hygiene practices, so as to prevent disease and promote positive attitudes towards cleanliness.
Hygiene promotion encompasses a systematic attempt to adequately promote personal, domestic, environmental and food hygiene practices that prevent or mitigate the transmission of diseases. Water purification programs is among the government programs that encourages hygiene practices.
The evidence that best supports conversation during photosynthesis is: Light energy is converted to chemical energy during photosynthesis ( A )
Photosynthesis is the process whereby plants make use of water and carbon dioxide found in the atmosphere to transform/convert the light energy from the sun into chemical energy.in the process of synthesizing food
The products of photosynthesis include oxygen and glucose while the conversion during photosynthesis takes place when the chloroplast absorbs the light energy from the sunlight and converts it another form of energy ( chemical energy ).
Hence we can conclude that The evidence that best supports conversation during photosynthesis is ; Light energy is converted to chemical energy during photosynthesis.
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Answer: The upper gastrointestinal tracts organs consist Esophagus, stomach and duodenum.
Explanation:
Gastrointestinal tracts is a organ system found in human beings and other animals that deals with intake of food, digestion of food, adsorbing nutrients from the digested food and expelling or excreting the waste products and undigested food.
The gastrointestinal tracts is divided into two, the upper and lower gastrointestinal tracts. The upper gastrointestinal tracts organs consist of Esophagus, stomach and duodenum while the lower gastrointestinal tracts consist of the large and small intestine. The structures include anus, colon,rectum,caecum.
Is made using the enzyme DNA polymerase, from the 5' to the 3' end?