Answer:
Cornwallis had marched his army into the Virginia port town earlier that summer expecting to meet British ships sent from New York. ... Cornwallis' surrender at Yorktown effectively ended the Revolutionary War. Lacking the financial resources to raise a new army, the British government appealed to the Americans for peace
Explanation:
What is the range for the following set of measurements 27 12 31 19 23 11 17?
11 Degrees C to 31 Degrees C
The range is 20
Answer:
a. different shape (e.g. flat or ribbon shaped).
d. larger internal surface area of the lungs.
Explanation:
Amphibians are cold blooded animals. They have a low rate of metabolism . Amphibians are located most where there is water or in moist environment because of their skin and how important it is to keep their skin moist.
Amphibians breathe through their skin and this can be called cutaneous respiration. Their lungs are not well developed therefore they undergo a very slow diffusion of oxygen through their blood.
For Amphibians that are larger than bull frogs, they obtain a very sufficient rate of diffusion of gases due to the following reasons:
a. Internal surface area of the lungs: Amphibians that are larger than bull frogs tend to have a more developed respiratory organs which means there lungs have a larger surface area and they are well developed.
b. They have a different body shape: Amphibians larger than bull frogs could have a flat or ribbon shape and their body shapes make it easier for respiratory gases like oxygen to permeate or enter their skin easily.
Answer:
Explanation:
The transformation of a zygote into an embryo adheres both to nature and to nurture: not only genetics but also environment determines the outcome. This idea has assumed many forms. A territory in the early sea urchin blastula contains clones of founder cells, and each clone contributes exclusively to one territory (Cameron & Davidson, 1991). Both the lineage of a founder cell, i.e. its nature, and the position of a founder cell, which determines how it is nurtured, contribute to its fate. Fertilisation, the topic of the first Forum, fixes the genes; interblastomere communication, the topic here, regulates gene expression. Blastomeres communicate like any other cell – via ligand-receptor interactions and through gap junctions. Saxe and DeHaan review these mechanisms. The definition of ligands and receptors becomes broadened in this context, and cell adhesions as well as gap junctions enter into the story. In spite of these entanglements, it appears that nature uses the same sorts of mechanisms to get cells to specialise that she uses to keep them talking. Thus, neurons and glial cells signal to one another via glutamate receptors and gap junctions (Nedergaard, 1994). Likewise, we expect neurotransmitters (and neurotransmitter transporters) to help signal differentiation. The biophysicist may ask whether electrical properties also play a role, but that we reserve for another Forum. If gap junctions figure in development as fusion pores that pass small molecules and electrical signals between blastomeres, another parallel suggests itself. Brian Dale asked in the first Forum: How does a spermatozoon activate an oocyte? This question, which concerns gamete communication, has produced two schools of thought and remains controversial (Shilling et al., 1994). Do sperm activate oocytes via contact-mediated mechanisms or through fusionmediated mechanisms? Or do both mechanisms occur, as they appear to in development?
Cellular respiration<span> uses energy in glucose to make ATP. Aerobic (“oxygen-using”)</span>respiration<span> occurs in three </span>stages<span>: glycolysis, the Krebs cycle, and </span>electron transport<span>. In glycolysis, glucose is split into two molecules of pyruvate.</span>
