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3 years ago

Many natural cycles allow life on Earth to continue. One of them is the

Biology

1 answer:

Alex_Xolod [135]3 years ago

5 0

Answer:

D. Changing land use and burning fossil fuels.

Explanation:

Today, the carbon cycle is changing. Humans are moving more carbon into the atmosphere from other parts of the Earth system. More carbon is moving to the atmosphere when fossil fuels, like coal and oil, are burned. More carbon is moving to the atmosphere as humans get rid of forests by burning the trees.

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There is a population of beetles that typically have black wings. A scientist studying these beetles knows that their eggs hatch

ioda

Answer:

A) Black winged beetles have higher fitness than white winged beetles

Explanation:

Because after the white winged beetles have played their eggs they die

7 0

3 years ago

What are the end products of lactic acid fermentation and alcoholic fermentation?

3241004551 [841]

Lactic acid fermentation produces lactic acid, while alcoholic fermentation produces ethanol. Both fermentation pathways also oxidize NADH to NAD+ during the process.

4 0

3 years ago

Suppose that an arginine residue in the active site of an enzyme was mutated to alanine. As expected, the alanine mutant was ina

Makovka662 [10]

Answer:

Alanine to lysine.

Explanation:

Mutation may be defined as the sudden, heritable change in the genome sequence of an organism. Two main types of mutation are chromosomal mutation and point mutation.

The mutation has occurred in which the arginine is replaced by alanine. The mutation that can restore to wild type is the conversion of alanine with lysine. Since both arginine and lysine are basic amino acids. They both shows almost similar function and the replacement of lysine with alanine shows the wild type activity.

Thus, the answer is alanine to lysine.

5 0

3 years ago

Select all that apply.

professor190 [17]

The right answer is B and C.

For proposal C, I will give you an example, that of an autosomal recessive disease. If a parent is heterozygous for an allele causing an autosomal recessive disease (due to a mutation), it may be that it transmits the allele to its descendence, as it may not be able to transmit it (since in one heterozygous subject, not all of its gametes carry the mutated allele) and thus the mutation will no longer be copied through the generaitons.

Each individual is genetically unique. Its genes are distributed along chromosomes contained in the nucleus. Mutations can lead to the appearance of different versions of genes: alleles. A diploid individual has two copies of each gene, which may be identical or different alleles. Mixing during sexual reproduction partly explains the genetic diversity of individuals.

4 0

3 years ago

Read 2 more answers

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.