Why can black holes not be seen?

They have too much gravity for light to escape.

They are hidden in interstellar dust.

They exist only behind other stars.

Scientists don't know where to look for them.

Are ladybugs herbivores carnivores or omnivores

Your heart pumps blood at variable rates depending on your degree of physical activity or neural/hormonal activity (this is called heart rate). With exercise or fear, heart rate increases to pump more blood to an active body.

What kind of relationship do snails and green-banded broodsacs share? producer-consumer predator-prey parasite-host

Which of the following components of the immune system form memory cells after you receive a vaccine? Skin and saliva Monocytes and macrophages Neutrophils and histamines B and T cells

According to the World Wildlife Fund roughly when did humans start using more of Earth's resources than can be replenish

When a protein is denatured, why does it lose its functionality?

This is a rotating machine that converts the kinetic energy of the wind into mechanical energy. If the mechanical energy is used directly by machinery, such as a grinding stone, the machine is usually called a windmill.

In what way are slime molds similar to kelp?

What does not exist in a supersaturated solution

When dust and ash particles from a volcanic eruption block out sunlight and reduce solar radiation, earth experiences the. This results in temporary climate cooling