Cellular metabolism is a set of chemical reactions in an organism that aim to produce energy for the cells to function.
In addition to energy production, during cell metabolism there is also the synthesis of intermediates that participate in chemical reactions, such as lipids, amino acids, nucleotides and hormones. Therefore, cell metabolism is essential for the survival of organisms.
Cellular metabolism is divided into anabolism and catabolism.
O anabolism comprises the energy storage reactions, occurring the synthesis of compounds. It is the synthesizing phase of metabolism.
O catabolism understands the energy release reactions, from the decomposition of molecules. It is the degrading phase of metabolism.
ATP, the energy currency of cells
ATP (Adenosine Triphosphate) is the molecule responsible for capturing and storing energy. It is involved in the energetic reactions that take place in cells.
The main way to get ATP is through glucose. Cells break down glucose molecules to produce energy in the form of ATP. Via
glycolysis, glucose is broken down through ten chemical reactions that generate two ATP molecules as a balance.Know more:
- Metabolism
- Anabolism and Catabolism
Photosynthesis and Respiration
Photosynthesis and respiration are the most important processes of energy transformation in living beings.
THE photosynthesis it is a physical-chemical action that takes place at the cellular level. It occurs in chlorophylled beings, which from carbon dioxide, water and light, obtain glucose.
THE cellular respiration is the process of ATP formation through oxidation, using the oxygen as an oxidizing agent. During the process, reactions break the bonds between molecules, releasing energy. It can be performed in two ways: aerobic respiration (in the presence of ambient oxygen gas) and anaerobic respiration (without oxygen).
To learn more about energy reactions in cells, read also:
Krebs Cycle;
Oxidative Phosphorylation;
Fermentation;
energy metabolism
Exercises
1. (PUC - RJ-2007) These are biological processes directly related to cellular energy transformations:
a) respiration and photosynthesis.
b) digestion and excretion.
c) breathing and excretion.
d) photosynthesis and osmosis.
e) digestion and osmosis.
a) respiration and photosynthesis.
2. (ENEM 2009) Photosynthesis is important for life on Earth. In the chloroplasts of photosynthetic organisms, solar energy is converted into chemical energy that, together with water and carbon dioxide (CO2), it is used for the synthesis of organic compounds (carbohydrates). Photosynthesis is the only biologically important process capable of carrying out this conversion. All organisms, including producers, use the energy stored in carbohydrates to boost cellular processes, releasing CO2 into the atmosphere and water into the cell through cellular respiration. Furthermore, a large fraction of the planet's energy resources, produced both in the present (biomass) and in remote times (fossil fuel), is the result of photosynthetic activity.
The information on obtaining and transforming natural resources through the vital processes of photosynthesis and respiration, described in the text, allow us to conclude that:
a) CO2 and water are molecules with high energy content.
b) carbohydrates convert solar energy into chemical energy.
c) life on Earth ultimately depends on energy from the Sun.
d) the respiratory process is responsible for removing carbon from the atmosphere.
e) the production of biomass and fossil fuel, by itself, is responsible for the increase in atmospheric CO2.
c) life on Earth ultimately depends on energy from the Sun.
3. (ENEM-2007) When drinking a glucose solution (C6H12O6), a sugarcane cutter ingests a substance:
a) that, when degraded by the organism, it produces energy that can be used to move the body.
b) flammable which, when burned by the body, produces water to maintain cell hydration.
c) that it raises the blood sugar level and is stored in the cell, which restores the body's oxygen content.
d) insoluble in water, which increases fluid retention by the body.
e) of sweet taste which, used in cellular respiration, provides CO2 to keep the carbon content in the atmosphere stable.
a) that, when degraded by the organism, it produces energy that can be used to move the body.
