<span>In order for individuals best suited for growth and reproduction in a particular environment to contribute disproportionately to the next generation natural selection must take place. Natural selection is one of the basic mechanism of evolution. This mechanism leads</span> to adaptations and adaptations contribute to survival and reproduction.
Answer:
c. a proton gradient set up across the thylakoid membrane
Explanation:
During the photosynthesis (this also occurs in cellular respiration in mitochondria), hydrogen ions (H+) move across the thylakoid membrane down their electrochemical gradient (from the area of their higher concentration to the area with hydrogen ions lower concentration). An ion gradient can be used for the production of ATP.
Answer:
Arachnids, crustaceans, myriapods.
Explanation:
Arthropods are animals that form the phylum Euarthropoda. This phylum includes the arachnids, crustaceans, myriapods, and insects. The defining characteristic for an animal to be considered an arthropod is that it has to have an exoskeleton, meaning that the skeleton of the animal is acting as a shell to the body, covering it from the outside.
At present, all of the species of arthropods are small in size, though in the distant past there were speciemens that can be considered as medium-sized or even large. The exoskeleton has its advantages and disadvantages. An advantage is that it is very hard and it covers fully the internal organs, thus protecting them. A disadvantage is that it limits the size to which these animals can grow as the exoskeleton cannot support the weight of the body after certain point.