People with two copies of the sickle cell gene have the disease. People who carry only one copy of the sickle cell gene do not have the disease, but may pass the gene on to their children. Abnormal hemoglobin, called hemoglobin S, causes sickle cell disease (SCD). The problem in hemoglobin S is caused by a small defect in the gene that directs the production of the beta globin part of hemoglobin. This small defect in the beta globin gene causes a problem in the beta globin part of hemoglobin, changing the way that hemoglobin works.
To divide the sex cells or gametes
Answer:
The reason that there is no fruit even the plant produced healthy flowers maybe because
1. absences of pollinators due to declining poliinator population
2.weather conditions are preventing pollination
3. prevalence of flooding
Explanation:
1.Fruits are direct result of pollination. Due to the decrease in the number of pollinators especially orchid bees, some fruit bearing plants produce flowers but no fruit.
Bees decline their population because of parasites, diseases, exposure to chemicals and other environmental factors.
2.Unfavorable factors may prevent the agents of pollination to do their jobs. Bees and other insects may be hindered by wet or cold weather or some use of chemicals.
3.Brazil nut grow in lowland rainforest where there is no flooding.
The ribosomes on the rough endoplasmic reticulum (RER) most likely produces neuronal special proteins.
Explanation:
Conduction of electrical impulses by action potentials of neurons takes place through controlled flow of charged ions through neuronal membranes. This ion transfer is controlled by specialized neuronal channel proteins which are present in the neuronal cell membrane.
These channel proteins allow for hydrophillic passage of ions and water molecules across the neuronal membranes.
Ribosomes that are attached to the RER are involved in protein synthesis. They carry the code for proteins carried by the mRNA and translate into respective protein.
The RER along with some free ribosomes cluster together as Nissl bodies and are mainly involved in neuronal specialized proteins.
Answer:
Among the following statements shown, the most accurate concerning the founder effect is that (b) It results when a small population breakers away from a larger one. Founder Effect is defined as the reduced genetic diversity which is most likely caused when a population is descended from a small number of colonizing ancestors.
