Answer:
alveoli
Explanation:
They are the smallest structures in our lungs where capillaries exchange O2 and CO2 in blood.
Answer:
Predators are an important part of a healthy ecosystem. Predators remove vulnerable prey, such as the old, injured, sick, or very young, leaving more food for the survival and success of healthy prey animals. Also, by controlling the size of prey populations, predators help slow down the spread of disease.
1. Cellular respiration does not consume carbon dioxide (CO2).
Cellular respiration is a process by which plants produce energy. It consists of anaerobic (without O2) and aerobic phase(with the presence of O2). During the cellular respiration chemical energy derived from the nutrients (like glucose) is transformed into energy molecule adenosine triphosphate (ATP).
2. Unlike photosynthesis, cellular respiration occurs in all eukaryotic organisms (photosynthesis only in plants and some microorganisms). The processes of cellular respiration occur in cytosol (glycolysis) and in the mitochondrion of a cell (Krebs cycle and electron transport chain).
Coevolution happens when the genetic development between two or more species affects the evolution of each other. An example would be hummingbirds and bird-pollinated (ornithophilous) flowers. The ornithophilous flowers give nourishment to the birds with their nectar that has high sugar content. The birds in return aids in the pollination of these flowers.
Ans.
Steroids are defined as active organic bio-molecules, having four rings with a specific molecular configuration. Steroids play role in two major functions: as hormones or signaling molecules and as structural components of plasma membrane.
Examples of steroid hormones are estrogen, progesterone, and cortisol. Thus, the correct answer is 'option b). they serve as chemical messengers.'
