A&P Short Answer Ch. 25, 28, 29

Trace the path of a sperm cell from the site of its maturation to the site where it leaves the male body. Include descriptions of fluids added along that path.

-Sperm mature in the epididymis. -From there, they travel through the Vas deferens, through the abdominal cavity to the ampulla, -sperm moves through the seminal vesicle adding alkaline, fructose-rich fluid -goes through the ejaculatory duct into the prostatic urethra, where they are mixed with an acidic mucoid fluid from the prostate. -Next the sperm and fluid pass through the membranous urethra, and are mixed alkaline secretions from the bulbourethral glands. -The combination of sperm and secretions is called semen. -The mixture travels through the penile urethra as it is ejaculated.

Briefly outline the possible fates of glucose in the body

1. ATP production- glucose is oxidized to produce ATP. 2. Amino Acid Synthesis- Cells can use glucose to form amino acids to form proteins. 3. Glycogen Synthesis- Hepatocytes and muscle fibers can perform glycogenesis. 4. Triglyceride synthesis- When glycogen storage is filled up, hepatocytes can transform glucose to glycerol and fatty acids.

Describe the roles of estrogens and progesterone

Estrogens stimulate the growth, development and maintenance of the female reproductive structures. Progesterone works with estrogens to prepare the endometrium for implantation and to prepare the breasts for milk production.

Describe the hormonal events surrounding parturition.

Fetal CRH secretion increases, which causes estrogen to increase as fetal ACTH triggers an increase in cortisol and DHEA, which is converted to estrogen by the placenta. Estrogen increases oxytocin receptors on uterine smooth muscle fibers and makes them form gap junctions. Oxytocin stimulates uterine contraction, and relaxin dilates the cervix and loosens the pubic symphysis. Estrogen also increases prostaglandins to digest collagen in the cervix. Oxytocin the cervix, and the hypothalamus maintain a positive feedback loop to maintain labor

Distinguish between genotype and phenotype and explain how the environment may affect each.

Genotype- genetic make-up of an individual. Teratogens (agents that cause mutations) might damage the DNA and change the genotype. Phenotype - physical expression of the genes. Height, hair color... If the genotype is changed by the environment, the phenotype may also be changed. Phenotype is dependent on the environment in a variety of ways. One example is that a child might have the genotype "tall". If the child doesn't receive adequate nutrition, though, he could still be might not be as tall as his genes would ordinarily allow.

What are triglycerides split into?

Glycerol and fatty acids, a process called lipolysis

What is glycogenesis?

Hundreds of glucose monomers are combined to form the polysaccharide glycogen.

What are the possible fates of pyruvic acid in the body? What is the primary determinant of the fate of pyruvic acid? What is the fate of compounds to which pyruvic acid may be converted?

Oxygen is the primary determinant of the fate of pyruvic acid. 1. When oxygen is plentiful, pyruvic acid is converted to acetyl coenzyme A, and enters the Krebs cycle. 2. When oxygen is scarce, most pyruvic acid is converted to lactic acid. - rapidly diffuses out of body cells - into blood

Describe the products of the three primary germ layers.

THE ECTODERM nervous tissue THE MESODEM cartilage and bone THE ENDODERM lining of the gi tract

Describe the functions of testosterone.

Testosterone promotes the development and maintenance of male secondary sex characteristics, protein anabolism, development of sexual function (behavior, libido, spermatogenesis), and the male pattern of development during prenatal life.

What is glycolysis?

The 10 reactions that convert glucose to pyruvic acid.

What is reduction?

The addition of electrons to an atom or molecule. Increase the potential energy.

Red-green color blindness is a recessive, X-linked trait represented as Xc. (Normal color vision is represented as XC.) If a daughter has red-green color blindness, what must the genotypes of her parents be?

The daughter can only have red-green color blindness if she received two copies of X c chromosomes. Since her father only has one X chromosome, his genotype must be X c Y. The other X c chromosome had to come from her mother. If her mother has normal color vision, the mother's genotype is X C X c . However, if the mother is also color blind, the mother's genotype must be X c X c

What is glycogen?

The main polysaccharide in the human body, Made up of glucose monomers linked together forming a chain.

What is glycogenolysis?

The process of splitting glycogen into its glucose subunits.

What is oxidation?

The removal of electrons from an atom or molecule. Decrease the potential energy

Describe the role of the hypothalamus in regulation of food intake

Two hypothalamic areas involved in regulation of food intake are the arcuate nucleus and the paraventricular nucleus. When leptin and insulin levels are low, the arcuate nucleus to the paraventricular nucleus release neuropeptide y to stimulate food intake. Other neurons release Melanocortin to stop food intake.

Where in the cell does each of these processes occur? -electron transport chain (oxidative phosphorylation) -glycolysis -Krebs' cycle

electron transport chain (oxidative phosphorylation) -In the inner mitochondrial membrane glycolysis - in the cytoplasm of the cell Krebs' cycle- In the mitochondrial matrix