The dodo was placed in the kingdom Animalia because if fulfills all characteristics necessary to be defined as a member of that kingdom. This also means that it is a motile, multicellular, heterotroph with eukaryotic cells.
Answer:
The correct answer is: β1 adrenergic receptor activation. Increased in cAMP lead to increased amounts of Na influx (though if channels) and calcium influx of pacemaker cells. This increases the frequency of APs of the pacemaker and increases the rate of contraction.
Explanation:
cAMP generated in response to β1 adrenergic receptors,results in excitation contraction coupling by initiating PKA and causing phosphorylation of L type Ca2+ channels and ryanodine receptors. This increases the concentration of intracellular Ca2+ ions in atrial cells, ventricular cells and AV pacemaker cells. This increase in firing rate. As a result rate of contraction increases.
Answer:
In this case, it is likely that the polypeptide chain assumed an alpha helix configuration because the lipid bilayer did not have beta-barrel proteins.
Explanation:
A polypeptide chain is naturally polar, however, a lipid bilayer is naturally non-polar. This makes it difficult and even prevents the polypeptide chain from crossing a lipid bilayer, since the composition of these two elements does not allow them to mix. In that case, the polypeptide chain has two options to take to successfully cross the lipid bilayer.
The first option that the polypeptide chain has is to allow the creation of twisted beta sheets in the shape of a closed barrel in its structure. This only works if the lipid bilayer has beta barrel proteins in its composition to act as a transport channel for the polypeptide chain. However, few lipid layers have this protein.
Most likely, the polypeptide chain assumes an alpha helix conformation to cross lipid bilayers that do not have beta-barrel proteins. By assuming the beta conformation, the polypeptide chain reinforces the hydrogen bonds present in its composition, allowing it to cross the lipid bilayer without having its conformation and structure disassembled.
Collagenopathies refers to a group of disorders, which influences connective tissues. Connective tissues help to support the body's organs and joints. Collagens are the composite molecules, which offer strength, structure, and elasticity to the connective tissue.
The collagens are the constituents of the cartilage witnessed in joints. Therefore, defective collagen proteins lead to a defect in strength, structure, and elasticity of the connective tissue that eventually influences a person's mobility and stability.
Those trees cannot grow unless they are part of a larger, inter-connected community
each Interconnected communities usually benefit support the living of other organism simply by doing its own daily activities. Without it, it's hard for some organisms to survive on their own
