Response:
2 & 4
Explanation:
The concept of spontaneous generation proposed that life could arise from 'nothing.' This idea remained accepted until it was challenged by Francesco Redi and Luis Pasteur through experiments. Redi conducted an experiment where he placed cooked meat on two plates—one was covered with a glass bowl, while the other was left exposed. The covered plate did not develop maggots, but the open one did, indicating that maggots resulted from eggs laid by flies. Thus, life originates from pre-existing life.
Answer:
It is essential for living organisms to maintain a non-equilibrium state in the concentrations of oxygen and carbon dioxide to facilitate gas exchange. If equilibrium is reached, both respiration and photosynthesis would cease.
Explanation:
- Gases flow from areas of higher concentration to lower concentration along their gradients.
- If organisms achieve equilibrium in carbon dioxide and oxygen levels, gas exchange into and out of cells would stop.
- Equilibrium signifies that gas concentrations equalize on both sides, halting any movement.
- Should gas exchange come to a standstill, respiration and photosynthesis in plants, as well as respiration in animals, would completely halt.
Answer:
The respiratory system is comprised of specialized organs and structures for gas exchange in both animals and plants. The structure and function of this system differ significantly based on the organism's size, habitat, and evolutionary background. In terrestrial animals, the respiratory surfaces are typically the linings of the lungs. In mammals and reptiles, gas exchange occurs within millions of tiny air sacs known as alveoli, while birds have atria for this process. These tiny air sacs boast an extensive blood supply, ensuring air comes into close proximity with the bloodstream. They connect to the outer environment through airways or hollow tubes, with the trachea being the largest that divides in the chest into two primary bronchi. These then branch further into successively narrower secondary and tertiary bronchi, eventually leading to numerous smaller tubes called bronchioles. In birds, these are referred to as parabronchi. The air needs to be drawn into the alveoli or atria from the outside through the act of breathing, which involves respiratory muscles.
Explanation: