click below
click below
Normal Size Small Size show me how
AP2/ Exam 4
Chapters 27-29
Term | Definition |
---|---|
What is spermatogenesis? | Is the process of continues germ cell differentiation to produce spermatozoa, it is initiated at the time of puberty Cell division limited to gametes Mitotic proliferation Meiotic division Cell remodelling |
What is fetal circulation? | 1 way blood bypass nonaerated lungs way of the foramen ovale-obv circulatory diff btw fetus + neonate is the umbilical arteries + umbilical vein, tk bl to/from the placenta- incl few shunts : 3 shunts: ductus venosus, foramen oval, ductus arteriosus |
What is dominant allele | under most circumstances they suppress the expression of other alleles |
What are recessive genes | -usually expressed in humans only when both alleles are exactly the same, or homozygous -can only be expressed in the absence of the dominant allele |
Phenotype | the observable traits of an organism |
Genotype | organism's genetic make up for a specific trait |
What is genetic diversity | The total number of different alleles in a population -when increases: Random mutation, Migration or emigration -when decreases:Founder effect ,Genetic bottleneck, Selective breeding |
What is the process of Meiosis | -constancy of the chromosome # from one cell generation to the next, Spermatozoa are produced are genetically unlike each other + unlike the cells that produce them. Is the reason for great variation among humans. Caused by crossing over + ind assortment |
What is incomplete dominance | heterozygote has a phenotype intermediate between that of homozygous-dominant/recessive indivudals An individual who is heterozygous for a particular trait, yet expresses both alleles of that trait, is an example of incomplete dominance |
What is multiple allele inheritance | The presence of 3 or more alleles for a genetic trait. |
How does the environment influence genetic expression | Environmental factors such as food, drugs, or exposure to toxins can cause epigenetic changes by altering the way molecules bind to DNA or changing the structure of proteins that DNA wraps around. |
What are the chromosomes for males and females | -Males typically have two different kinds of sex chromosomes (XY), and are called the heterogametic sex. -Females typically have two of the same kind of sex chromosome (XX), and are called the homogametic sex. |
What is a chromosomal aberration | Physical and chemical damage or errors during mitosis or meiosis can damage chromosomes or alter the number of chromosomes in a cell |
Punnett's squares | a diagram used to visualize genetic crosses and genotype formations in offspring |
Phenotypic ratio for the punnett square | pertains to the relative num of offspring manifesting a particular trait or combination of traits. Determined by a test cross and identifying the frequency of a trait or trait combinations that will be expressed based on the genotypes of the offspring. |
What is the most common type of fetal testing | Amniocentesis |
What is Huntington's disease and what part of the brain is affected | Hyperactivity in basal ganglia circuitry - Also cortical involvement (Fatal genetic disorder > causes progressive breakdown of nerve cells in the brain). -affects the basal ganglia organize muscle-driven movements of the body, or “motor movement.” |
Amys hand has been exposed to x rays, the genes in the skin of her cell begin to mutate. Will this mutation be carried over to her off spring? And why? | It will replicate itself when the cell divides but will NOT be passed on to Amy's offspring |
What are sex linked characteristics? | genes located only on X-chromosomes The main way a recessive allele would be expressed even when only one copy is present would be sex-linked inheritance Sex linked characteristics: inherited traits determined by genes on the sex chromosomes |
Blood type punnett square | Used for blood typing to predict a child's possible genotypes based on the blood types of his parents |
A blood represents itself as Iai. Type B represents Ibi and determine what blood types their children will have | Half of the children predicted to be Type A and half Type B |
Gene mutations in sex chromosomes occur more frequently in females or males? | A male with a mutation in a gene on the X chromosome is typically affected with the condition. Because females have two copies of the X chromosome and males have only one X chromosome, X-linked recessive diseases are more common among males than females. |
APGAR test given when child is born | TRUE |
Which test is not routinely screened for in gene mutations | Temperature |
Process of cleavage involves- structures specifically (also on lab exam) | After fertilization, the development of a multicellular organism proceeds by a process of a series of mitotic divisions whereby the enormous volume of egg cytoplasm is divided into numerous smaller, nucleated cells. |
What hormones are involved in lactation | Hormone Prolactin secreted by the pituitary gland in the brain is responsible for the alveoli making milk. Prolactin rises when the baby suckles. Another hormone Oxytocin that causes tiny muscles around the alveoli to squeeze the milk via milk ducts. |
Where does the implanted embryo receive nutrition from ( doesn’t have cord or placenta) | Prior to receiving nutrients from the placenta, the conceptus (developing embryo) will receive nutrients from 2 sources: Uterine milk and trophoblastic nutrition |
What is a trophoblast | a layer of tissue on the outside of a mammalian blastula, supplying the embryo with nourishment and later forming the major part of the placenta. |
What are the 3 layers of the embryo and what tissue is derived from each layer | ectoderm include epithelium of the pineal and pituitary gland mesoderm include endothelium of blood and lymph vessels endoderm include epithelium of the respiratory tract 3 germ layers, the mesoderm forms the most body parts |
In discussion of development of cardiovascular system when the fetus is delivered what changes take place in the heart | cardiovascular system of a newborn must be adjusted after the infant takes its first breath. The ductus arteriosus contricts and is converted to the ligamentum arteriosum Blood no longer bypasses the lungs through the ductus arteriosus and formane ovale |
Stages of delivery | Dilation stage Expulsion stage Placental stage |
Dilation Stage | onset of regular contractions and ends with complete dilation of the cervix (averages 10 to 12 hours) 0-3 cm dialated, 5-8 minutes apart, lasting 20-30 seconds |
Expulsion Stage | starts with complete dialation of the cervix and goes to the birth of the baby. 4-7 cm dialated, 3-5 minutes apart lasting 40-60 seconds |
Placental Stage | with the delivery of the infant and ends with the delivery of the placenta 7-10 cm dialated, 32-3 minutes apart, lasting 80 seconds or more |
What hormone is not produced by placenta | inhibin |
Parturition (word for delivery) | The process of bringing a child into the world. 3 stages Dilation stage Expulsion stage Placental stage |
What is a teratogen and what are the most common teratogen | external agent that may produce/increase incidence of congenital defects following exposure tranquilizer thalidomide |
When does the non gender specific period end | |
What is ligamental teres | not a correct matching of a fetal structure with what it becomes at birth: ductus arteriosus-ligamentum teres Is the remnant of the umbilical vein |
In menstrual cycle. What is involved | Human chorionic gonadotropin maintains viability Not a part of the proliferative phase of the female menstrual cycle If fertilization occurs, the corpus luteum is maintained by a hormone secreted by the developing embryo |
What is the decidia basalis | The area of endometrium between the implanted chorionic vesicle and the myometrium, which becomes the maternal part of the placenta. located deep to the implanted blastocyst |
What is the function of the blood testis barrier | is formed between Sertoli cells of the seminiferous tubule and as such isolates the further developed stages of germ cells from the blood |
Structures of the male reproductive system | The external structures of the male reproductive system are the penis, the scrotum and the testicles 3 parts or the penis: the root, which attaches to the wall of the abdomen; the body, or shaft; and the glans, which is the cone-shaped end |
Structures of the female reproductive system | ovaries, oviducts, and the uterus, vagina, + external genital structures. Internal -uterus, vagina, + ovaries located w/in the ovaries, oviducts, and the uterus, vagina, + external genital structures. Internal -uterus, vagina, + ovaries located w/in ligam |
When ovulation occurs what site does fertilization take place in female genital | Fertilization occurs in the uterine tube |
Difference betwwen haploid and diploid | If gametes were diploid like somatic cells, the zygote would contain twice the diploid number, and with every succeeding generation, the chromosome number would continue to double and normal development could not occur |
What are the derivatives of mammary glands | mammary or milk- producing glands are found in all mammals. The glands are built on the same general plan though variations occur. Each gland is made up of a number of lobules. Each lobule consists of a number of alveoli which contain the secretory cells. |
When does the normal menstrual cycle begin | Hormones rise and fall. This is your menstrual cycle. It starts on the first day of your last period and ends on the first day of your next period. Though the average cycle is 28 days long, anything between 21 and 45 days is considered normal |
What is the difference between spermatogenesis and oogenesis | in oogenesis, one mature ovum is produced, and in spermatogenesis four mature sperm are produced from the parent cell |
During ejaculation why doesn’t semen enter urinary bladder | The smooth muscle sphincter at the base of the urinary bladder closes. |
What hormone is essential for ovulation to occur | LH- Luteinizing hormone |
How hormones are released increased/decreased during ovarian cycle | High estrogen levels result in a surge of LH release |
What are STD's | Sexually transmitted disease- an infection transmitted through sexual contact, caused by bacteria, viruses, or parasites |
How does STD affect the reproductive system in males and females | Syphillis is caused by a virus that may lead to death if untreated Gonorrhea is caused by a bacteria that can bring on very painful discharges. Chlamydia is caused by bacteria that can bring on a wide variety of nonfatal but uncomfortable symptoms. |
IN REBUILDING THE ENDOMETRIUM, what hormone plays vital role in the process | Not true: rebuilding the endometrium is under the control of prolactin |
Boy thought superman, inured anterior pituitary gland. FSH is no longer produced . His LH levels normal. How does that affect him. | One would expect that he would be unable to produce viable sperm |
What is prostate cancer | sometimes a slow-growing cancer that may never represent a threat to the patient |
What does the duct system in males include | The duct system of the male reproductive system includes the ductus deferens, a duct that runs from the epididymis up into the pelvic cavity Does not include corpus spongiosum |
When is an ovulating oocyte actually activated prior to ovulation | An ovulating oocyte is actually activated by hormones about 110 days before ovulation |
What is the fetal circulation pathway? | Circulating blood bypasses the lungs + liver by flowing in diff pathways + through special openings- shunts. Blood flow in the unborn baby follows this pathway: O2 +nutrients from the mother's blood are-->the placenta to the fetus ---> the umbilical cord. |
founder effect in the decrease of genetic diversity | Few organisms start new colony as may be geographically isolated from the rest of the population Small number of different alleles Increase in genetic disease Eg:Amish |
Genetic bottleneck in the decrease of genetic diversity | Event causes a large reduction in population Reduced number of different alleles in population this reduced genetic diversity Eg:northern elephant seals |
selective breeding in the decrease of genetic diversity | Breed two organisms with desirable characteristics Reduced variety of alleles in population thus genetic diversity |
Prophase I | DNA of chromosomes coils up and a spindle forms. DNA coils, homologous chromosomes line up w/ each other, to form a 4 part structure called a tetrad. |
Metaphase 1 | Centromere of each chromosome becomes attached to a spindle fiber. Spindle fibers pull the tetrads into the middle of the spindle. |
Anaphase 1 | Homologous chromosomes separate. Each new cell will receive only ONE chromosome from was homologous pair. |
Telophase 1 | Reverse order of prophase 1. Spindle is broken down, chromosomes uncoil Cytoplasm divides to yield 2 new cells |
Prophase 2 | spindle forms in each of the two new cells and the spindle attaches to the chromosomes, are pulled to the center of the cell and line up randomly |
Metaphase 2 | The chromosomes become arranged on the metaphase plate, much as the chromosomes do in mitosis, and are attached to the now fully formed spindle. |
Anaphase 2 | begins as as the centromere of each chromosome splits, allowing the sister chromatids separate ad move to opposite poles |
Telophase 2 | nuclei re-form, the spindles break down, cytoplasm divides |
Chromosomal aberrations (numerical) Polyploidy | Somatic cells contain multiples of haploid number of chromosomes (3n, 4n, 5n etc.). 3n or triploidy is most common -Mechanisms, Failure of pulling apart of 2 chromatids to opposite ends after metaphase stage of mitosis (nondisjunction) |
Chromosomal aberrations (numerical) Aneuploidy | Deviation from the diploid number of chromosomes (2n + 1, 2n -1 etc) -Mechanisms, Non-disjunction or the failure of separation of chromosomes during cell division. |
Genotypic ratio for the punnett square | describes the number of times a genotype would appear in the offspring after a test cross. For example, a test cross between two organisms with same genotype, Rr, for a heterozygous dominant trait will result in offspring with genotypes: RR, Rr, and rr |
When two genes are on the same chromosome, they are considered linked | TRUE |
delayed action genes can result in fatal diseases | TRUE |
the expression of all physical traits is strictly due to the inheritance of specific genes | FALSE |
some segments of the y chromosome have no counterpart on the x chromosome | TRUE |
the same allele can have a different effect depending on which parent it comes from | TRUE |
alleles may code for alternative expressions of a genetic trait | TRUE |
environmentally produced phenotypes that mimic conditions that may be caused by genetic mutation are called phenocopies | TRUE |
mitochondrial genes are free of errors. as a result, all genetic problems are due exclusively to nuclear genes | FALSE |
recessive genes are usually expressed in humans only when a. both alleles are exactly the same, or homozygous b. the organism is in the embryonic stage c. they are coding for genetic diseases d. they are coding for skin colour | a. both alleles are exactly the same, or homozygous |
those characteristics that can be determined on superficial inspection of an individual are known as a. polygenic b. polyspermic c. genotypic d. phenotypic | d. phenotypic |
is genetic diversity due entirely to inherited genes on the sex chromosomes? | no, because genetic diversity has nothing to do with the sex chromosomes but is due to crossing-over of chromosomes, independent assortment of chromosomes, and segregation of chromosomes |
a female infant is born with several hundred oocytes, each one genetically unique. this is due to a. recessive inheritance b. chromosome deletion c. independent assortment and random crossover d. mutation | c. independent assortment and random crossover |
the reason recessive genetic disorders are more frequent than disorders inherited as dominant is that | carriers are not eliminated by the disease before passing the defective alleles on to their offspring |
the gene responsible for the condition known as sickle-cell anemia demonstrates a. incomplete dominance b. a recessive genetic disorder c. a dominant genetic disorder d. a sex-linked genetic disorder | a. incomplete dominance |
a woman has blond hair and brown eyes. this statement is best described as indicating a. genotype b. allelic pairs c. recessive traits d. phenotype | d. phenotype |
Gene mutations in the sex chromosomes of the human would tend to become visibly expressed ____. A. in neither males or females B. more frequently in males C. more frequently in females D. equally frequently in both sexes | B. more frequently in males |
The dilation stage | this begins when true labor starts |
The expulsion stage | which ends in parturition, or the birth of the baby |
The placental stage | is the expulsion of the placenta from the uterus. |
This component of the male duct system carries sperm from outside the body into the abdominal cavity. | ductus deferens |
T OR F: Pain during ovulation is called dysmenorrhea. | FALSE |
The primary function of the uterus is to ________. | receive, retain, and nourish a fertilized ovum |
Which of the following hormones stimulates the release of anterior pituitary gonadotropins? | GnRH |
The cells that produce testosterone in the testis are called ________. | interstitial cells |
The spermatic cord ________. | carries blood vessels, nerves, and the ductus deferens between abdomen and scrotum |
The penis contains three elongated cylinders of erectile tissue. Select the most dorsal tissue. | corpora cavernosa |
T OR F: It is necessary for the testes to be kept below body temperature. | TRUE |
T OR F: The hormone oxytocin combines with enzymes in semen to enhance sperm motility. | FALSE |
T OR F: The male urethra serves the urinary system only | FALSE |
The ability of sperm cells to move along the ductus deferens is due to ________. | peristaltic contractions |
Sperm is stored in the ______. | epididymis |
T OR F: The amount of testosterone and sperm produced by the testes is dependent on the influence of FSH alone. | FALSE |
T OR F: The stage in meiosis where chromosomal exchange takes place is telophase. | FALSE |
Which of the following statements about sperm is not true? | THE SPERM MIDPIECE CONSISTS OF MITOCHONDRIA SPIRALED TIGHTLY AROUND THE CONTRACTILE FILAMENTS OF THE TAIL. |
Which male hormone directly inhibits the secretion of FSH? | inhibin |
Which of the following statements about spermatogenesis is not true? | EACH SPERMATID FORMS TWO SPERM. |
A low secretion of luteinizing hormone (LH) in the normal male adult would cause ________. | decreased testosterone secretion |
T OR F: The diamond-shaped area between the coccyx, pubic arch, and ischial tuberosities in the female is the vulva. | FALSE |
Which of the following statements is true concerning the mammary glands of both males and females? | The mammary glands are modified sweat glands that are actually part of the integumentary system. |
Which of the following is false regarding the vagina of an adult female? | THE PH OF THE ADULT VAGINA IS ALKALINE. |
Teresa has been complaining of severe abdominal pain, vaginal discharge, and a low-grade fever. What might be the doctor's diagnosis, and how should the condition be treated? | Pelvic inflammatory disease, treated with broad spectrum antibiotics. |
T OR F: The smaller cell produced by oogenesis meiosis I, called the first polar body, is essentially a packet of discarded nuclear material. | TRUE |
T OR F: The corpus luteum secretes progesterone only. | FALSE |
Which is not a part of the proliferative phase of the female menstrual cycle? | CORPUS LUTEUM |
A follicle with only a small antrum in it would be classified as a(n) ________ follicle. | secondary |
What role does the corpus lutem play in the menstrual cycle | The corpus luteum is the ruptured follicle following the ejection of an oocyte from the ovary regression of the corpus luteum and a decrease in ovarian progesterone secretion occur simultaneously |