Biology, 27.03.2020 21:45, jaedenevan062907
Biologists believe that eukaryotic cells arose from the endosymbiosis of prokaryotio cells. In this theory, prokaryotic cells (endosymbionts) took up residence inside much larger prokaryotic cells (the hosts). Modern-day mitochondria may be descendants of engulfed, heterotrophic bacteria that eould use oxywen to refeabe energy from onganic molecules through aerobic respiration. These specialised prokaryotes were not digest ed by the hosts, but remained alive inside vacuoles of the host cell, performing the same energy-production processes they had done when they were separate organiama Chloroplasts may be descendants of photosynthetic prokaryotes that could capture the energy of sunlight and use that energy to produce organic molecules from CO, The phylogenetic tree depicted in Figure 7.2 shows these evolutionary scenarios)
a. Which is greater: the proportion of modern-day eukaryotes that have mitochondria, or the proportion of modern-day eukaryotes that have chloroplasts?
b. What does this suggest about the sequence of evolutionary developments leading to mitochondria and chloroplasts? (In other words, which more likely came first: mito- chondria or chloroplasts?)
c. What modern day bacteria are likely to be most similar to the chloroplast ancestor?
d. Protists were formerly classified based primarily on their method of locomotion. Name a cell structure some protists have that enable them to move from place to place that some bacteria species also have. (Hint: By looking ahead to the protists that you will examine in lab, you might get a clue).
Answers: 1
Biology, 22.06.2019 02:00, gabe3636
Which of the following describes a negative feedback loop? when the heart rate is too high, the body sends hormones that continually increase the heart rate higher. when a pregnant woman is in labor, the body sends hormones that increase the intensity of contractions, which then increases the secretion of the same hormones. when blood sugar is too low, the body sends hormones that raise blood sugar until it reaches a typical level and hormone secretion slows. when a person is jogging, the body sends hormones that continually decrease the rate of oxygen supply to the legs.
Answers: 1
Biology, 22.06.2019 13:10, weridness80
Match the correct terms to their descriptions a system in which only energy but not matter is exchanged frozen water in snow part of geosphere that includes only soil a thin layer between the troposphere and the stratosphere cryosphere tropopause closed system pedosphere
Answers: 2
Biologists believe that eukaryotic cells arose from the endosymbiosis of prokaryotio cells. In this...
Mathematics, 02.03.2021 21:40
Chemistry, 02.03.2021 21:40
Mathematics, 02.03.2021 21:40
Mathematics, 02.03.2021 21:40
Mathematics, 02.03.2021 21:40
Geography, 02.03.2021 21:40