All of the cells within a complex multi-cellular organism such as a human being contain the same DNA; however, the body of such an organism is clearly composed of many different types of cells.
<u>What, then, makes a liver cell different from a skin or muscle cell</u> is <em>the way each cell deploy (utilizes) its genome</em>. In other words, the particular combination of genes that are turned on (expressed) or turned off (repressed) dictates cellular morphology (shape) and function. This process of gene expression is <em>regulated by cues</em> from both within and outside cells, and the<em> interplay </em>between these cues and the genome <u>affects essentially all processes</u> that occur during embryonic development and adult life.
Outside/Environmental cues include small molecules, secreted proteins (growth factors or signaling molecules), temperature, and oxygen.
The signaling molecules trigger intercellular signaling cascades (series of chemical reactions) that ultimately cause semipermanent changes in expression of genes. Such changes in gene expression can include turning genes completely on or off.
This process is thought to regulate a vast number of cell behaviors, including cell fate decisions during embryogenesis, cell function, and chemotaxis (i.e. cell movement in response to concentration gradient of a particular substance.)
Answer:
Plants and other producers generate their own energy, which allows them to grow, reproduce, and live. They are the only living organisms on the planet that can produce their own supply of food energy, which makes them unique. They, of course, require sunlight, water, and air to survive.
<u>OAmalOHopeO</u>
Answer:Carbon has four valence electrons, so it can achieve a full outer energy level by forming four covalent bonds. When it bonds only with hydrogen, it forms compounds called hydrocarbons. Carbon can form single, double, or triple covalent bonds with other carbon atoms.
Explanation:
Hypothalamus.
pituitary gland.
thyroid.
parathyroids.
adrenal glands.
pineal body.
reproductive glands (depending on the sex)
pancreas.
Answer:
The genotypic frequency = 1:1
The phenotypic frequency = 1:1
Explanation:
Given that:
The allele → R = Red beetles
The allele → B = Blue beetles
Since the gene color shows a codominant allele
The Red Beetle = RR
The blue beetles will be = BB
The heterozygous beetle will be = RB
∴
The punnet square showing the crossing of RB × RR is:
R B
R RR RB
R RR RB
The result shows that we have two red beetles and two heterozygous beetles.
Hence;
The genotypic frequency = 1:1
The phenotypic frequency = 1:1