Red blood cells are also known as _________?
erythrocytes
thrombocytes
phagocytes
leucocytes
Correct answer is A
Red blood cell aslo kn own as erythrocytea disk-shaped, biconcave cell in the blood that contains hemoglobin, lacks a nucleus, and transports oxygen and carbon dioxide to and from the tissues
White blood cells or leukocytes, are cells of the immune system involved in defending the body against both infectious disease and foreign materials.
Platelets, or thrombocytes or yellow blood cells, are very small, irregularly shaped clear cell fragments (i.e. cells that do not have a nucleus containing DNA. Platelets are a natural source of growth factors. They circulate in the blood of mammals and are involved in hemostasis, leading to the formation of blood clots.
Phagocytes are cells that protect the body by ingesting harmful foreign particles, bacteria, and dead or dying cells.
The biome that is characterized with large herbivores, few and scattered fire resistant trees is
savanna
tropical rain forest
montane forest
desert
Correct answer is A
Savannas are quite low in tree species diversity because of stringent ecological requirements but fairly high in diversity of herbaceous plants. Tree growth is controlled not only by rainfall but also by soil type; large areas of hardpan soils, allow no tree roots to penetrate except through cracks, and the cracks determine tree distribution.
Large mammals are at their most diverse in this open environment, in which they can move about freely and yet find shelter among woody vegetation. Large herbivores are successful because of the tremendous biomass of herbaceous vegetation produced annually, and there are many carnivores to crop them in turn.
Tropical rain forests occur in areas of tropical rainforest climate in which there is no dry season, distinct buttress roots of trees.
Montane forest refers to any ecosystem found in mountains. These ecosystems are strongly affected by climate, which gets colder as elevation increases.
A desert is a barren area of landscape where little precipitation occurs and consequently living conditions are hostile for plant and animal life.
The matured sex cell which takes part in sexual reproduction is referred to as
gamete
fetus
embryo
zygote
Correct answer is A
Gametes are reproductive cells (sex cells) that unite during sexual reproduction to form a new cell called a zygote. Male gametes are sperm and female gametes are ova (eggs).
Embryo is the stage of animal development in the uterus before the animal is considered a fetus. In humans this is equivalent to the first three months.
Which of the following organs is responsible for the production of insulin?
Spleen
Adrenal gland
Thyroid gland
Pancreas
Correct answer is D
No explanation has been provided for this answer.
The maintenance of a constant internal environment in an organism is known as
homeostasis
homoiothermy
diuresis
dialysis
Correct answer is A
No explanation has been provided for this answer.