Ques: Q: What are the contacts between neurons called? Read this paragraph and choose the correct option from the provided answers: 12.5 Communication Between Neurons The basis of the electrical signal within a neuron is the action potential that propagates down the axon. For a neuron to generate an action potential, it needs to receive input from another source, either another neuron or a sensory stimulus. That input will result in opening ion channels in the neuron, resulting in a graded potential based on the strength of the stimulus. Graded potentials can be depolarizing or hyperpolarizing and can summate to affect the probability of the neuron reaching threshold. Graded potentials can be the result of sensory stimuli. If the sensory stimulus is received by the dendrites of a unipolar sensory neuron, such as the sensory neuron ending in the skin, the graded potential is called a generator potential because it can directly generate the action potential in the initial segment of the axon. If the sensory stimulus is received by a specialized sensory receptor cell, the graded potential is called a receptor potential. Graded potentials produced by interactions between neurons at synapses are called postsynaptic potentials (PSPs). A depolarizing graded potential at a synapse is called an excitatory PSP, and a hyperpolarizing graded potential at a synapse is called an inhibitory PSP. Synapses are the contacts between neurons, which can either be chemical or electrical in nature. Chemical synapses are far more common. At a chemical synapse, neurotransmitter is released from the presynaptic element and diffuses across the synaptic cleft. The neurotransmitter binds to a receptor protein and causes a change in the postsynaptic membrane (the PSP). The neurotransmitter must be inactivated or removed from the synaptic cleft so that the stimulus is limited in time. The particular characteristics of a synapse vary based on the neurotransmitter system produced by that neuron. The cholinergic system is found at the neuromuscular junction and in certain places within the nervous system. Amino acids, such as glutamate, glycine, and gamma-aminobutyric... Choices: - neurapses - impulses - electrodes - synapses A:
Ans: synapses

Ques: Q: What is driven by the sun's energy and moves water over the surface of earth? Read this paragraph and choose the correct option from the provided answers: The Sun heats some areas more than others, which causes wind. The Sun's energy also drives the water cycle, which moves water over the surface of the Earth. Both wind and water power can be used as renewable resources. Choices: - sun cycle - tides - weather cycle - the water cycle A:
Ans: the water cycle

Ques: Q: How many calories of energy does one gram of sugar or starch provide? Read this paragraph and choose the correct option from the provided answers: Carbohydrates include sugars, starches, and fiber. Sugars and starches are used by the body for energy. One gram of sugar or starch provides 4 Calories of energy. Fiber doesn't provide energy, but it is needed for other uses. At age 13 years, you need about 130 grams of carbohydrates a day. Figure below shows good food sources of each type. Choices: - 5 - 3 - 10 - 4 A:
Ans: 4

Ques: Q: Each vertebral body has a large hole in the center through which the nerves of what pass? Read this paragraph and choose the correct option from the provided answers: Each vertebral body has a large hole in the center through which the nerves of the spinal cord pass. There is also a notch on each side through which the spinal nerves, which serve the body at that level, can exit from the spinal cord. The vertebral column is approximately 71 cm (28 inches) in adult male humans and is curved, which can be seen from a side view. The names of the spinal curves correspond to the region of the spine in which they occur. The thoracic and sacral curves are concave (curve inwards relative to the front of the body) and the cervical and lumbar curves are convex (curve outwards relative to the front of the body). The arched curvature of the vertebral column increases its strength and flexibility, allowing it to absorb shocks like a spring (Figure 38.8). Intervertebral discs composed of fibrous cartilage lie between adjacent vertebral bodies from the second cervical vertebra to the sacrum. Each disc is part of a joint that allows for some movement of the spine and acts as a cushion to absorb shocks from movements such as walking and running. Intervertebral discs also act as ligaments to bind vertebrae together. The inner part of discs, the nucleus pulposus, hardens as people age and becomes less elastic. This loss of elasticity diminishes its ability to absorb shocks. The Thoracic Cage The thoracic cage, also known as the ribcage, is the skeleton of the chest, and consists of the ribs, sternum, thoracic vertebrae, and costal cartilages (Figure 38.9). The thoracic cage encloses and protects the organs of the thoracic cavity, including the heart and lungs. It also provides support for the shoulder girdles and upper limbs, and serves as the attachment point for the diaphragm, muscles of the back, chest, neck, and shoulders. Changes in the volume of the thorax enable breathing. The sternum, or breastbone, is a long, flat bone located at the anterior of the chest. It is formed from three bones that fuse in the adult. The ribs are 12 pairs of long, curved bones that attach to the thoracic... Choices: - layers cord - Brain Cord - steering cord - spinal cord A:
Ans:
spinal cord