Water is a polar molecule because its opposite ends have opposite electric charges.
Answer:
carbon source Earth's crust
Transmitted, vertical
A transparent specimen is viewed through a microscope using transmitted light while an opaque object requires vertical illumination.
Transmitted light is the light that passes through an object. Transmitted light microscopy is any kind of microscopy in which the light is transmitted from a source located directly across the specimen from the objective. The light is commonly passed through a condenser in order to focus it on the specimen to obtain very high illumination. After the light passes through the specimen, the image of the specimen moves through the objective lens and later to the oculars where the enlarged image is viewed.
Continuous conduction takes place in unmyelinated axon.
Explanation:
Based on the presence and absence of myelin sheath, the neurons had been classified as myelinated and non-myelinated neurons respectively.
In myelinated neurons the transmission of impulse takes place only at the non myelinated region called nodes of Ranvier. Due to this, the conduction in Myelinated neuron is saltatory.
The conduction in non-myelinated neuron takes place throughout the length of axon and it is continuous.
Saltatory conduction is faster than continuous conduction.
Answer:
The correct answer is D. The surface of the skin can be mapped into distinct regions, each served by a single spinal nerve: these regions are called dermatomes.
Explanation:
A dermatome is the area of skin innervated by a single spinal nerve and its spinal ganglion. The cutaneous nerves are those that reach the skin, picking up the sensitivity of the skin. Each cutaneous nerve is distributed in a certain area of skin, called a dermatome.
A pair of posterior or sensory roots and a pair of anterior or motor roots arise from each cord segment, joining laterally at the level of the intervertebral foramen to form a mixed spinal nerve. Each of these innervates a strip of skin called a dermatome, so the body surface can be considered a true mosaic of these.
In the extremities the arrangement of dermatomes is more complicated because of the embryological rotation of the limbs as they grow from the trunk.
