Answer:
The correct answer will be option E.
Explanation:
The features given in the question are the characteristics features of the group of bacteria belonging to Cyanobacteria.
These Cyanobacteria are the prokaryotes which are capable of synthesizing the food through a process called photosynthesis. These bacteria use sunlight as their energy, use water and air to synthesize food. They under anaerobic condition synthesize the nitrogen in special structures called heterocyst, a characteristic feature of cyanobacteria.
Thus, the features given in the question are:
1. contain photosystems to carry out photosynthesis.
2. producing oxygen
4. contain phycobilins
6. Hetrocysts: nitrogen-fixing structures.
7. The ancestor of plant chloroplasts.
Thus, option E is the correct answer.
The ability of water to hold more heat than land keeps the temperature on Earth on a moderate level.
Photosynthesis is a process used by plants and other organisms to convert light energyinto chemical energy that can later be released to fuel the organisms' activities. This chemical energy is stored in carbohydrate molecules, such as sugars, which are synthesized from carbon dioxide and water – hence the name photosynthesis, from the Greek φῶς, phōs, "light", and σύνθεσις, synthesis, "putting together".[1][2][3] In most cases, oxygen is also released as a waste product. Most plants, most algae, and cyanobacteria perform photosynthesis; such organisms are called photoautotrophs. Photosynthesis is largely responsible for producing and maintaining the oxygen content of the Earth's atmosphere, and supplies all of the organic compounds and most of the energy necessary for life on Earth.[4]
Although photosynthesis is performed differently by different species, the process always begins when energy from light is absorbed by proteins called reaction centresthat contain green chlorophyll pigments. In plants, these proteins are held inside organelles called chloroplasts, which are most abundant in leaf cells, while in bacteria they are embedded in the plasma membrane. In these light-dependent reactions, some energy is used to strip electrons from suitable substances, such as water, producing oxygen gas. The hydrogen freed by the splitting of water is used in the creation of two further compounds that serve as short-term stores of energy, enabling its transfer to drive other reactions: these compounds are reduced nicotinamide adenine dinucleotide phosphate(NADPH) and adenosine triphosphate (ATP), the "energy currency" of cells.
In plants, algae and cyanobacteria, long-term energy storage in the form of sugars is produced by a subsequent sequence of light-independent reactions called the Calvin cycle; some bacteria use different mechanisms, such as the reverse Krebs cycle, to achieve the same end. In the Calvin cycle, atmospheric carbon dioxide is incorporatedinto already existing organic carbon compounds, such as ribulose bisphosphate(RuBP).[5] Using the ATP and NADPH produced by the light-dependent reactions, the resulting compounds are then reducedand removed to form further carbohydrates, such as glucose.
Crossing over can create genetic variation. Crossing over is when chromosomes cross over they give + take a part of another chromosome which can create different variation in genes.
