What characteristic differentiates cardiac muscle cells from skeletal muscle cells?

Aneuron is stimulated with an electric pulse. the action potential is detected at a point 3.70 cm down the axon 0.0052 s later.when the action potential is detected 7.20 cm from the point of stimulation, the time required is 0.0063 s. what is the speed of the electric pulse along the axon? (why are two measurements needed instead of only one? )

Approximately 90% of all cases of polycystic kidney disease are inherited in an autosomal dominant fashion. the disease is typically related to mutations to genes (pkd1 and pkd2). pkd genes can be found on chromosome 16. the disease occurs in approximately 1: 800 to 1: 1000 people. here is a hypothetical example. the dominant allele d will cause the development of pkd. the recessive allele is known as d. what genotypes would correspond to suffering from pkd? dd, dd what genotypes would correspond to being normal (not suffering from pkd)? dd consider that 1: 1,000 people have pkd in your population of 325million. consider that pkd is inherited in an autosomal dominant fashion. show you math for all of the following questions: what is the genotypic frequency for dd? what is the genotypic frequency for dd? what is the genotypic frequency for dd? what is p? what is q? how many people in your population would have pkd?

In the diagram below, the northern hemisphere would be in what season at position a a.fall b. winter c.summer d.spring