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3 years ago

How struggle for existence drove evolution of organism—————pleasee

1 answer:

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Answer: In On the Origin of Species, Darwin claimed that there was a continual 'struggle for existence' in nature, in which only the fittest would survive. This theory came partly from his reading of Thomas Malthus's Essay on the Principle of Population.

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In an article about saving the whales written by a marine biologist, which word might be used by the author to make you want to

fgiga [73]

Answer:

Endangered

Explanation:

Endangered species are organisms that are at risk of extinction if deliberate efforts are not made to conserve them due to a rapid decrease in their population.

Hence, if a marine biologist writes an article about saving whales and labels them as endangered species, all efforts should be geared towards saving the animals lest they go extinct and leave a vacuum in the functioning of the ecosystem. Every species have the critical roles they play in the functioning of the ecosystem and the extinction of any particular species represents a loss that might not be replaceable.

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3 years ago

Read 2 more answers

In the universal ABO blood grouping system, there are four phenotypes—A, B, AB, and O—which are determined by three different al

charle [14.2K]

Answer:

The correct answer is - autosomal codominant inheritance (due to multiple alleles).

Explanation:

Autosomal codominant inheritance or codominance is a pattern of inheritance where the alleles present of an autosomal gene express their character in the phenotype. In other words, in this type of pattern, no allele would be masked by other alleles and both will be expressed in the phenotype.

The human ABO blood group is an example of this pattern as there are three alleles A, B, and O. In the heterozygous case of AB blood group both A, and B alleles expressed together however, O is masked by both alleles A, and O.

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3 years ago

Which answer best explains the difference between protists and bacteria?

Delvig [45]

Answer:

The correct option is A. Bacteria are prokaryotes and protists are eukaryotes

Explanation:

The major difference between BACTERIA AND PROTISTS is the Bacteria are PROKARYOTES in nature and they dont have what we called nucleus reason been that their microbes are single celled microbes while protists on the other hand are EUKARYOTIC in nature and they have nucleus and they can either have a single-celled or have more than one celled.

The Second difference is that protists can only be found in the area or surrounding that are mostly moisture while bacterial on the second hand can be found in every area, environment or surrounding.

Therefore the answer that best explains the difference between both protists and bacteria

Is option A which states that Bacteria are PROKARYOTES while protists are EUKARYOTES.

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3 years ago

1. Which scientist developed the heliocentric model for the solar system?

Llana [10]

Answer: B. Copernicus

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3 years ago

Describe the process of light-independent

xxTIMURxx [149]

Explanation:

Light energy is absorbed and transferred to the reaction center.
A water molecule is split.
Electrons are transferred from photosystem II to photosystem I.
ATP is synthesized from ADP and inorganic phosphate.

Output: ATP, NADPH, O2

Further Explanation:

Photosynthesis is a chemical pathway that’s integral to producing energy in plants and other primary producers. Energy in the form of molecules of glucose is produced from light, water and carbon dioxide while oxygen is released. This occurs in several complex steps, photosynthesis is a rate limited reaction, depends on several factors including carbon dioxide concentration, ambient temperature and light intensity; the energy is retrieved from photons, I.e. particles of light, and water is used as a reducing agent. This occurs in the thykaloids, where pigment molecules like chlorophyll reside.

The chloroplast is a membrane bound organelle found in plants. It contains several invaginations of a plasma membrane called the thylakoid membrane. This contains chlorophyll pigments, in stacks called granum, while the internal spaces of the organelle are called the lumen. Liquid surrounds the granum, forming the stroma.

During the light reaction:

Light is absorbed by pigments in phosystem II (PSII). This energy is transferred among pigments til it gets to the reaction center, and is transferred to P680; this promotes an electron to a higher energy level where it then goes to an acceptor molecule.
Water supplies the chlorophyll in plant cell with replacement electrons for the ones removed from photosystem II. Additionally, water (H2O) split by light during photolysis into H+ and OH- acts as a source of oxygen along with functioning as a reducing agent.
the electron moves down an electron transport chain (to PS I)where it experiences continuous energy loss. This energy fuels the pumping of H+ from the stroma to thykaloid, leading to the formation of a gradient. The H+ move along their gradient and cross through ATP synthase, into the the stroma.
ATP synthase converts ADP and Pi to the energy storage molecule ATP.
The electron gets to photosystem I where it goes to pigments at P700. It absorbs light energy, the electron is promoted to a higher energy level, and passed to an electron acceptor. This leaves a space for another electron which is then replaced by one from photosystem II.
in the ETC, the molecule NADP is reduced to NADPH by providing H+ ions. NADP and NADPH are integral to the Calvin cycle where monosaccharides or sugars like glucose are produced after the modification of several molecules.