Answer:
The claim is valid because the lac operon allows a bacterial cell to shut down a metabolic pathway if it is not immediately needed.
Explanation:
The lac operon is a cluster of genes which contain the same promoter sequence and are transcribed as a single messenger RNA (mRNA). This operon is inducible because the presence of lactose in the cell influences its transcription. Lactose can bind to the repressor of this operon, leading to a conformation change in the repressor, thereby preventing the repressor from binding to the operator and thus allowing transcription of the structural genes. After lactose addition, the β- galactosidase enzyme can break this carbohydrate into glucose and galactose, thereby there is no lactose able to bind with the repressor and therefore this operon shuts down. During transcription, the promoter of the lac operon binds both RNA polymerase and catabolite activator protein (CAP) and cyclic AMP (cAMP) complex.
Answer:
The outer mitochondrial is highly permeable while the inner membrane is highly convoluted.
Explanation:
Permeable is that property of cell membrane which allows micromolecules to go inside or comes outside the cell. Mitochondria is the power house of the cell which is responsible for the production of energy from food molecules such as glucose. There are two parts of mitochondria i. e. outer mitochondrial membrane and inner mitochondrial membrane. The inner mitochondrial membrane is convoluted means folded many times.
Answer:
Skin cells live about two or three weeks. Colon cells have it rough: They die off after about four days. Sperm cells have a life span of only about three days, while brain cells typically last an entire lifetime (neurons in the cerebral cortex, for example, are not replaced when they die).
Explanation:
Answer:
Explanation:
during crossing over the two non-sister chromatids change their segments
and it results in genetic recombination which causes difference between parents and their offspring
Answer:
1.Using fossils as a base
2.Creation of the tissues and muscles out of clay.
Explanation:
The fossils available are used as a base for the reconstruction of the face. Without the well preserved and near complete skull there is no possibility. There must be a good level of preservation of fossils in order to reconstruct the fossils.
The sticks are first placed to approximate the depth of tissues over the bone. The tissues and muscles are molded out of the clay.
Finally the detailed painting creates the skin color, texture and expressions of the facial reconstruction.
