They must be homozygous for that trait
Answer:
The correct option is <em>B. Crossing- over </em>
Explanation:
In biology, crossing over can be described as a phenomenon by which homologous chromosomes exchange segments during the process of meiosis.
The unexpected results came because the DNA segment between the homologous chromosomes was exchanged during meiosis. The alleles got shuffled by this process and hence showed the unexpected results.
Crossing over and independent assortment are phenomenon which occurs only during the process of meiosis. These phenomenons cannot be observed during mitosis.
Answer:
Ligand-receptor interaction is the first interaction that triggers cell signalling.
Ligands are the hormones, drugs or neurotransmitters that specifically bind with receptors present in cell surface to initiate cell signalling. Ligand binding to the receptor is reversible. Binding of the ligand to the receptor can activate or inactivate receptor. Activation may lead to cell signalling pathways. Inside cells, there are secondary molecules which on activation starts a cascade of reactions. which in-turn regulate the function of the ligand molecule.
At first, the activated receptor relates with G proteins molecules in the cell.
before the ultimate physiological effect of the ligand on the cell's behavior is produced Therefore, the cellular signaling starts as soon as the first messenger (the ligand) binds to its receptor.
hope this helps
Answer:
Viruses. no metabolism not alive can not be killed ... The symptoms from a viral infection occur when the virus is in a lytic state. steps: attachment- ... biosynthesis- phage DNA directs synthesis of viral components by host cell ... Viral DNA destroys Cell DNA, takes over cell functions and destroys the cell.
Answer:
A. 25 °C, 30 °C, 35 °C, 40 °C, 45 °C
Explanation:
Each enzyme has a temperature at which it works best. In humans and many animals, that temperature is around body temperature (37 °C or 98.6 °F). Most enzymes are denatured and work poorly at 40 °C (104 °F).
That automatically eliminates Option B.
I would pick a temperature close to 37 °C (98.6 °F) and temperatures at intervals above and below that.
Option D is wrong because it includes no temperatures above body temperature.
Option C is wrong, because it includes temperatures of 45 °C and 55 °C, at which the enzymes will be denatured.
That leaves Option A as the best answer. It includes only one temperature above 40 °C.
