Answer:
A. donation of excited electrons by chlorophyll a to a primary electron acceptor
Explanation:
Photosystems are structures located at the thylakoid membrane that act to harvest energy light in order to convert it into chemical energy. Each photosystem is composed of a light-harvesting complex and a core complex, which in turn is composed of a reaction center. The photosynthetic reaction centers are multi-protein complexes that use light energy to catalyze the electron transfer across the chloroplast thylakoid membrane against a thermodynamic gradient. Moreover, antenna pigments are pigments that capture the energy from photons in order to transfer energy to other pigments in the photosystem (e.g., chlorophyll B and carotenes are antenna pigments, whereas chlorophyll A is the core pigment). Light energy absorbed by antenna pigments in the photosystems is transferred to the reaction center chlorophyll A molecules, thereby exiting electrons in the reaction center. A reaction center consists of two chlorophyll A molecules, which donate electrons to the primary electron acceptor.
Answer:
The mecanism is termed as feedback inhibition.
Explanation:
In an enzyme catalyzed sequential reaction the end product of that reaction inhibits the activity of the activity of the enzyme catalyzing the ist step This type of regulation is called Feed back regulation or feedback inhibition.
The main function of human body is to maintain the homeostasis of the all the components it contains.When the end product of an ongoing enzyme catalzsed sequential reaction is produced in a high lebel at that time to maintain its own homeostatis that end product inhibits the functioning of the enzyme catalzsing the ist step of that biochemical reaction.
For Example Cytidine tri phosphate inhibits the activity of aspartate transcarbamoylase catalyzing the de novo biosynthesis pathway of pyrimidine metabolism.
Cytokinesis is the division of the cytoplasm.
Mitosis the nuclear division.
hope this helps
Answer:
Valine-Leucine-Proline-Lysine-Histidine
Explanation:
The central dogma of biology is the process by which DNA is used to synthesize RNA and subsequently amino acid sequence (PROTEIN). The processes of transcription and translation is used in gene expression. Transcription is the process whereby the information encoded in a DNA molecule is used to synthesize a mRNA molecule. Transcription is catalyzed by RNA polymerase enzyme, which uses complementary base pairing rule i.e Adenine(A)-Thymine(T), Guanine(G)-Cytosine(C) pairing.
N.B: Thymine is replaced by Uracil in the mRNA
For the above DNA sequence: CAC GAC GGA TTC GTA, the mRNA sequence will be: GUG CUG CCU AAG CAU
Translation is the second process of gene expression which involves the synthesis of an amino acid sequence from an mRNA molecule. The mRNA is read in a group of three nucleotides called CODON. Each codon specifies an amino acid (see attached image for genetic code)
Based on the attached genetic code, an mRNA sequence: GUG CUG CCU AAG CAU will encode an amino acid sequence: Valine(Val) - Leucine (Leu) -Proline (Pro) -Lysine (Lys) - Histidine (His).
GUG specifies Valine amino acid
CUG specifies Leucine amino acid
CCU specifies Proline amino acid
AAG specifies Lysine amino acid
CAU specifies Histidine amino acid