Hemoglobin is

A. a digestive enzyme.

B. a tiny nutrient carried in capillaries.

C. an oxygen-carrying pigment in blood.

D. part of the vertebrate nervous system.

Which of the following is NOT a type of epithelial cell

How many fish species are prescent on the reef.

What new character did john dalton add to the model of the atom

Calcula la fuerza de atracción entre dos personas. Asume que los dos cuerpos tienen la misma masa (100 Kg) y que la distancia entre ellas es d = 1 m El valor de G=10-11 N. m2/kg2

The organelle within both plant and animal cells that functions to regulate what can enter or exit a cell.

One of the main differences between natural selection and genetic drift is that A) genetic drift happens by chance B) genetic drift populations introduce new species C) genetic drift populations are selected by nature D) genetic drift populations

Hatchetfish live in very deep parts of the ocean. What challenges must they overcome to survive in this environment?

The movement of air particles around a vibrating object is a

About how much of the United States is covered by forests? A 90% B 10% C 50% D 30%

What is the layer underground where all empty spacess are filled with water