Answer:
a. It has a negative value.
b. It is measured in millivolts.
c. It is measured in millivolts.
Explanation:
Resting membrane potential is typically ~ -70 millivolts so options a, b and c are correct, rest are false statements.
The resting membrane potential is -70 millivolts because more K+ is inside the neuron while more Na+ is outside the neuron and it reflects more negative voltage in the cytosol as compared to the interstitial fluid.
As soon as stimulus arrives, it causes more Na+ to move inside the neuron making the membrane potential as +20 millivolts and the neuron is said to be in 'depolarized state'. Soon after that K+ starts to move outside of the neuron and since K+ has positive charge and it is moving out of the cell so the membrane becomes more and more negative inside and at this time neuron is said to be in 'hyperpolarised state'.
Answer:
The form of circulatory shock known as hypovolemic shock is the condition when the plasma level of blood and the body fluids level is decreased rapidly causing insufficient level of oxygen in the blood . the form of shock caused by anaphylaxis any condition in which blood vessels are inadequately filled and blood cannot circulate normally shock that results from large-scale loss of blood volume, or after severe vomiting or diarrhea always fatal
Explanation:
- hypovolemic shock is one type of shock among different kinds of shock. it happens when body fluids or blood plasma level starts to decrease rapidly due to some internal or external injury such as bleeding, dehydration, burns, and severe vomiting, diarrhea.
- later causes body fluid loss which decreases the o₂ level in blood.
- this causes lack of o₂ supply in organs which is indeed a fatal condition.
Answer:
<em>Many scientists opposed the "cell theory" </em>when it was first introduced because they believed that <u>even "non-living matters" could produce or generate a living tissue.</u> This was called<em> </em><em>"spontaneous generation."</em><em> </em>The appearance of the fly's larva<em> (maggots)</em> on meat supported this belief of theirs.
It was Louis Pasteur who was able to disprove this concept.
Explanation:
The discovery of cell came about when the microscope was invented. It was first discovered by Robert Hooke, an English natural philosopher in the <em>1600s</em>. However, he wasn't really sure about the structure and function of the cell during his time. It was Anton van Leeuwenhoek, a Dutch scientist, who proposed that "<em>motility"</em> is a quality of life.
Developing the cell theory was credited to Theodor Schwann and Matthias Schleiden.
The correct answer is:
Codominance
Answer:
Answer is option A.
Orchid bees are to Brazil nut trees as breezes are to pine trees.
Explanation:
In Brazil nut trees, the female orchid bees act as pollinators that help in pollination. In pine trees, wind or breeze helps in pollination.
Pine trees are gymnosperms and so they do not have flowers to attract pollinators like bees or butterflies or birds. They are wind-pollinated. Pine trees are monoecious i.e., both male and female reproductive structures (pine cones) are present on the same tree.
The male cones (catkins) produce pollen grains that are lightweight, less sticky and have air bladders or small wing-like structures. As a result of these features, the pollen grains can be easily carried and dispersed by the breeze. In order to prevent self pollination (pollen falling on the female cones of the same tree), the male cones are normally located on the lower branches of the pine tree.
The female cones are located on the upper branches of the tree and the center of the cone contains eggs or ovules. The pollen grains that are carried by the wind, fall on the female cone of another pine tree. Each pollen grain grows a pollen tube into the center of the cone and the nucleus cell of the pollen travels through the tube and reaches the egg, where it combines with the egg to form an embryo. The embryo eventually grows into a seed. The seeds of pine trees are then dispersed by wind or animals such as squirrels.