<span>It may be difficult for ecologists to determine the size of a bird population if that population migrates to different locations throughout the year. During migration, some birds may split off from the group and not return, others may die, and still others may join. Therefore, the bird population will be in constant flux. It is hard to know, when the birds return to their prior location, if the population consists of the same group of birds (in addition to deaths and births) or whether it has grown or shrank through other means. However, to estimate the size, an ecologist can track a migratory flock through several years, counting each year to get a general sense of the population size. Additionally, given one measurement, an ecologist could consider the average lifespan and birth rates of the population to extrapolate the size of the population in subsequent years.</span>
Answer:
4. cannot be made by the body and therefore must be consumed to maintain health.
Explanation:
Essential nutrients are nutrients that our body cannot synthesized and also those nutrients our body cannot produced in sufficient quantity, for the normal functioning of the body. These nutrients have to be obtained from the food we consume to support our life and health.
Essential nutrients obtained from food include carbohydrates, fats and oils, proteins, water, as well as certain vitamins and minerals. These essential nutrients that we get from our food are needed for good growth and development, prevention of diseases, as well as for maintaining good health.
Answer:
Herbívoros
Explanation:
Son animales que se alimentan exclusivamente de plantas, pastos, hierbas y vegetales en general. Hay muchos herbívoros que comen huevos y a veces otras proteínas provenientes de animales. Ejemplos de herbívoros: caballo.
Answer:
stethoscope is the instrument used to measure heart beat
