Answer:
P wave and R wave
Atrial contraction = P wave
Ventricular contraction = R wave
Explanation:
The behavior of the frog heart from force recording can be classified into ; P wave and R wave.
utilizing the ECG ( Electrocardiogram) data the aspect of the force recording that is due to atrial contractions is the ; P wave while the force recording that is due to ventricular contractions is the ; R wave the ventricular contractions is also known as QRS
ECG is used to record the electrical activities of a heart at rest
Answer:
Natural selection
Explanation:
Natural selection occurs when one allele (or combination of alleles of different genes) makes an organism more or less fit, that it is able to survive and reproduce in a given environment. If an allele reduces fitness, its frequency will tend to drop from one generation to the next.
Next, Mendel took the F1 progeny and allowed them to self-fertilize. In the resulting F2 generation, 3/4 showed the dominant phenotype, and 1/4 showed the recessive phenotype. ... 1 out of 3 round pea plants from the F2 generation were true-breeding and produced only offspring with round peas.
A challenge to traditional (pre-1860) ideas about species came from embryology, when it was discovered that embryos of dissimilar organisms, such as sharks and humans, resemble each other. Embryology involves the study of the formation and the development of an embryo and the fetus. It is one type of evidence of evolution such that the embryos of many different kinds of animals, mammals, reptiles, birds, fish among others, are similar showing a common ancestry.