Genetics and Man PDF

Genetics and Man  inborn errors 1. Hereditary fructose intolerance is a disorder in which a person lacks the protein needed to break down fructose. This condition occurs when the body is missing an enzyme aldolase B. The body cannot change...

Genetics and Man  inborn errors 1. Hereditary fructose intolerance is a disorder in which a person lacks the protein needed to break down fructose. This condition occurs when the body is missing an enzyme aldolase B. The body cannot change its stored form of sugar (glycogen) into glucose. As a result, blood sugar falls 2. Galactosemia is a condition in which the body is unable to use (metabolize) the simple sugar galactose. If both parents carry a nonworking copy of the gene that can cause galactosemia, each of their children has a 25% (1 in 4) chance of being affected with it.  inborn errors 3. Maple syrup urine disease (MSUD) is a disorder in which the body cannot break down certain parts of proteins. The urine of people with this condition can 4. Phenylketonuria (PKU) is a rare condition in which a baby is born without the ability to properly break down an amino acid called phenylalanine.  Behavioral studies heritability of behavioral traits, and Genetics it overlaps with genetics, psychology, and ethology (the scientific study of human and animal behavior). The Influence of Behavior on Genes Behavior can influence genetic expression in humans and animals by activating or deactivating genes. Behavior can have an impact on genetic makeup, even as early as the prenatal period. It is important to understand the implications of behavior on genetic makeup to reduce negative  Drugs and Fetal alcohol syndrome affects both physical and mental Alcohol development, damaging neurons within the brain and often leading to cognitive impairment and below-average weight. Exposure to drugs and alcohol can also influence the genes of children and adults. Addiction is thought to have a genetic component, which may or may not be caused by a genetic mutation resulting from  Temperatur e Temperature exposure can affect gene expression. Himalayan rabbits, the genetic expressions of fur, skin, and eyes are regulated by temperature. In the warm areas of the rabbits’ bodies, the fur lacks pigment due to gene inactivity and turns white. Fig. 1 Himalayan rabbit: Exposure to cold On the extremities of the temperatures activates pigment-producing genes in the rabbit’s extremities. rabbits’ bodies (nose, ears and feet) the gene is activated and  Light exposure Those exposed to certain light frequencies had corresponding wing colors when they became butterflies (for example, red produced vibrant wing color, whereas blue led to pale wings). Darkness resulted in the palest wing color, leading him to conclude that light exposure influenced the genes of the butterflies. In this manner a caterpillar’s behavior can directly affect gene expression; a caterpillar that actively seeks out light will appear  Nutrition Lack of proper nutrition in early childhood is yet another factor that can lead to the alteration of genetic makeup. Human children who lack proper nutrition in the first three years of life tend to have more genetic problems later in life, such as health issues and problems with school performance.