input: OPTIONS:
- low vitamin D
- radiation
- weight gain
- age Now, answer this question: Answer the following question given this paragraph: Unlike bones and tendons, which need to be strong as well as elastic, the arteries and lungs need to be very stretchable. The elastic properties of the arteries are essential for blood flow. The pressure in the arteries increases and arterial walls stretch when the blood is pumped out of the heart. When the aortic valve shuts, the pressure in the arteries drops and the arterial walls relax to maintain the blood flow. When you feel your pulse, you are feeling exactly thisthe elastic behavior of the arteries as the blood gushes through with each pump of the heart. If the arteries were rigid, you would not feel a pulse. The heart is also an organ with special elastic properties. The lungs expand with muscular effort when we breathe in but relax freely and elastically when we breathe out. Our skins are particularly elastic, especially for the young. A young person can go from 100 kg to 60 kg with no visible sag in their skins. The elasticity of all organs reduces with age. Gradual physiological aging through reduction in elasticity starts in the early 20s. Q: What causes reduction of elasticity in all organs? A:
A:
output: age

Answer the following question given this paragraph: Q: Spiders use the hydrostatic pressure generated by an open type of what anatomical system to extend their legs? A:

OPTIONS:
- respiratory
- pulmonary
- vascular
- circulatory

Answer: circulatory

Problem: OPTIONS:
- strength
- work
- light
- gravity
Q: Answer the following question given this paragraph: Weight measures the force of gravity pulling downward on an object. The SI unit for weight, like other forces, is the Newton (N). On Earth, a mass of 1 kilogram has a weight of about 10 Newtons because of the pull of Earth's gravity. On the moon, which has less gravity, the same mass would weigh less. Weight is measured with a scale, like the spring scale shown in the Figure below . The scale measures the force with which gravity pulls an object downward. To delve a little deeper into weight and gravity, watch this video:. Q: What is the force that pulls downward on an object and is measured by weight? A:
Answer: gravity

Problem:OPTIONS:
- nicotine
- chewing tobacco
- alcohol
- tobacco smoke

Answer the following question given this paragraph: tobacco smoke causes fatal lung disease in nonsmokers. Q: What still causes fatal lung disease in nonsmokers? A:
****
A: tobacco smoke

Answer the following question given this paragraph: Insects are arthropods in the class Hexapoda. They are the most numerous organisms in the world. Most are terrestrial, and many are aerial. Insects have six legs and a pair of antennae for sensing chemicals. They also have several eyes and specialized mouthparts for feeding. Insects are the only invertebrates that can fly. Flight is the main reason for their success. Insects may live in large colonies and have complex social behaviors. Insects spread disease and destroy crops. However, they are essential for pollinating flowering plants. Q: Insects are arthropods in which class? A:
OPTIONS:
- lexapoda
- trichina
- xerophyte
- hexapoda
hexapoda

Answer the following question given this paragraph: Insects are the only invertebrates than can fly. Flight is the main reason for their success. Q: The only invertebrates than can fly belong to what broad group, which is highly successful? A:
OPTIONS:
- spiders
- birds
- bats
- insects

Answer:
insects