Exam 3 - Reproduction
Anatomy of Penis
- Shaft - Glans (head) - Prepuce (foreskin)
Three Layers of Cells in Uterus
1. Endometrium 2. Myometrium 3. Perimetrium
True or false? The production of sperm begins at puberty when spermatogonia undergo meiosis I to form primary spermatocytes, which then undergo meiosis II to form secondary spermatocytes. These secondary spermatocytes go on to form spermatids, which mature into sperm cells. A) True B) False
B
What is the relationship between Leydig cells and Sertoli cells? A) Leydig cells develop into Sertoli cells during the process of spermatogenesis. B) Leydig cells stimulate gametogenesis in males, and Sertoli cells stimulate gametogenesis in females. C) Leydig cells produce tropic hormones that trigger the release of hormones by Sertoli cells. D) Leydig cells stimulate the production of sperm cells, and Sertoli cells nourish developing sperm. E) Leydig cells produce one male sex hormone, and Sertoli cells produce another male sex hormone.
D
Clitoris
Homologous to glans of penis; contains spongy erectile tissue that consists of a head, shaft, and prepuce
Internal Fertilization
Male deposits sperm in or near female reproductive tract, fertilization takes place inside female; requires cooperation between male and female
Sexual Arousal in Females
Structures fill with blood (vasocongestion); vaginal wall releases lubricant, along with greater/lesser vestibular gland and the paraurethral glands
Resolution in Females
1. Body returns to normal 2. Don't have refractory period
Resolution in Males
1. Body returns to normal 2. Enter refractory period (minutes to hours)
Sexual Arousal in Males
1. Bulbourethral gland secretes its fluid 2. Penis becomes erect due to blood filling spongy erectile tissue that makes up shaft (vasocongestion)
Sperm Journey - During Ejaculation
1. Epididymis --> Vas Deferens 2. Pass seminal vesicle 3. Ejaculatory Duct 4. Urethra
Four Types of Asexual Reproduction
1. Fission 2. Fragmentation/Regeneration 3. Budding 4. Parthenogenesis
Sperm Journey - Before Ejaculation
1. Form via meiosis in testes 2. As they mature in seminiferous tubules, transported to epididymis
Two Types of Sexual Reproduction
1. Hermaphroditism 2. Sex Reversal
External Structures of Female Reproductive System
1. Labia Majora 2. Labia Minora 3. Vaginal Orifice 4. Urethral Orifice 5. Clitoris
Sexual Reproduction Process
1. Meiosis --> Gametes (haploid) 2. Sperm fertilizes egg --> Zygote (diploid)
Egg Journey
1. Produced via meiosis in ovaries 2. Pushed out of ovary 3. Drawn into oviduct 4. Transported toward uterus
Orgasm & Ejaculation in Males
1. Semen pushed into urethra (emission) 2. Semen pushed out of tip of penis (expulsion) 3. Capillary beds open
Four Components of Semen
1. Sperm 2. Seminal vesical secretions 3. Prostate gland secretions 4. Bulbourethral gland secretions
Internal Structures of Female Reproductive System
1. Uterus 2. Cervix 3. Vaginal Canal/Vagina 4. Vaginal Orifice
Sperm Component of Semen
10%; mixed in isotonic salt water solution
Flaccid Penis Size
3-4 inches long; 1 inch in diameter
Prostate Gland Component of Semen
30%; thin, milky; contains buffers, ions, carbs, and enzymes that cause semen to coagulate and then later become thin and runny
Erect Penis Size
5-7 inches long; 1.5 inches in diameter
Seminal Vesical Component of Semen
60%; thick, yellow, alkaline; contains carbs, prostaglandins, and proteins needed to coagulate semen
Bulbourethral Gland Component of Semen
<1%; clear alkaline mucus; "pre-cum"; neutralizes urine in urethra
Immediately after ovulation, an egg is collected into the __________. A) oviduct B) cervix C) ovary D) uterus E) vagina
A
Pheromones are __________. A) generally effective at very low concentrations B) an adaptation that originated in vertebrates to facilitate mating C) a strong influence on human reproductive behavior D) functional only in terrestrial environments E) typical only in species with internal fertilization
A
The human female's external reproductive structures are ___________. A) the clitoris, two sets of labia, and vaginal opening B) the endometrium, two sets of labia, and clitoris C) one set of labia, bulbourethral gland, and clitoris D) the cervix, clitoris, and vaginal opening E) the cervix, one set of labia, and vaginal opening
A
True or false? Humans form gametes by a process called gametogenesis. A) True B) False
A
Which of the following is an accurate statement about sexual reproduction? A) Most animals produce offspring by sexual reproduction. B) Sexual reproduction preceded the evolution of asexual reproduction. C) Animals that have sexual reproduction do not reproduce by asexual means. D) Sexual reproduction is a vertebrate adaptation. E) Sexual reproduction requires sexual intercourse.
A
Environmental Cues and Reproduction
Affect hormone levels in individual; individual's biology and behavior are affected
A hermaphrodite is ___________. A) any asexually reproducing individual B) an individual with both male and female reproductive systems C) the result of a developmental abnormality D) an organism that reproduces clonally in order to produce colonies of genetically identical individuals E) an organism lacking the ability to produce eggs
B
From a single cell, oogenesis in a mammal will produce __________. A) four eggs B) an egg and two or three polar bodies C) four spermatozoa D) four polar bodies E) a primary oocyte
B
Sperm exit a male's body via the _____. A) ejaculatory duct B) urethra C) oviduct D) ureter E) epididymis
B
What products are formed when a diploid cell undergoes meiosis? A) Two haploid cells. B) Four haploid cells. C) Four diploid cells. D) Two diploid cells.
B
Which of the following choices correctly lists the four phases of the sexual response cycle in their proper sequence? A) Plateau, excitement, orgasm, and resolution B) Excitement, plateau, orgasm, and resolution C) Excitement, plateau, resolution, and orgasm D) Excitement, orgasm, plateau, and resolution E) None of the listed responses is correct
B
Which of the following correctly traces the path of sperm from their site of production to their exit from a man's body? A) vas deferens → epididymis → urethra → seminiferous tubule B) seminiferous tubule → epididymis → vas deferens → urethra C) seminiferous tubule → vas deferens → epididymis → urethra D) epididymis → urethra → seminiferous tubule → vas deferens E) epididymis → seminiferous tubule → vas deferens → urethra
B
Which of the following is a difference between the reproduction of humans (and other primates) and the reproduction of all other mammals? A) Only the penis of humans (and other primates) has erectile tissue. B) Only humans (and other primates) have menstrual cycles. C) Primates have longer gestations than all other mammals. D) Estradiol plays a role only in the regulation of primate reproduction. E) Mammals other than primates lack secondary sexual characteristics.
B
Which of the following is an accurate statement about parthenogenesis? A) Offspring produced by parthenogenesis are all haploid. B) Parthenogenesis appears rarely in vertebrates. C) Many animals will reproduce by parthenogenesis if kept in isolation for long periods. D) Parthenogenesis is not an effective reproductive strategy. E) Parthenogenesis does not occur in insects.
B
Which part of the human sperm carries a haploid set of chromosomes? A) Vitelline layer B) Head C) Acrosome D) Neck E) Middle piece
B
Fragmentation/Regeneration
Body broken into pieces; regeneration of missing body parts on each piece (flat worms)
Animals utilizing external fertilization are typically _____. A) insects B) land animals C) aquatic animals D) animals that reproduce asexually E) mammals
C
How does spermatogenesis differ from oogenesis? A) Gamete maturation occurs after fertilization in spermatogenesis. B) Production of the cells that will mature into gametes is complete by birth in spermatogenesis. C) Diploid cells give rise to four functional gametes in spermatogenesis. D) Gametes are produced by meiosis in spermatogenesis.
C
In humans, oogenesis in comparison to spermatogenesis is different in that _____. A) female puberty typically occurs much later than the age of male puberty B) oogenesis continues throughout life, but spermatogenesis typically ends at age 55 years C) oogenesis does not complete meiosis until after fertilization, but spermatogenesis is complete before the sperm leave the body D) oocyte production works best at cooler temperatures than those that support spermatogenesis E) the names and chemical identities of the pituitary hormones are completely different between males and females
C
Sexual reproduction includes a reproductive pattern called _____. A) budding B) regeneration C) hermaphroditism D) fission E) fragmentation
C
Sperm develop in the _____. A) prostate gland B) bulbourethral glands C) seminiferous tubules D) hypothalamus E) seminal vesicles
C
What is an advantage of internal fertilization? A) Internal fertilization does not require communication. B) Internal fertilization requires less complicated reproductive systems. C) Internal fertilization can occur outside of aquatic or marine habitats. D) Internal fertilization allows for the production of a greater number of eggs. E) Internal fertilization is less energetically costly.
C
What role do germ cells play in gametogenesis? A) They produce cells that undergo meiosis and develop into gametes. B) They produce cells that divide by mitosis to form gametes. C) They produce cells that divide by mitosis and then undergo meiosis to form gametes. D) They produce gametes.
C
Which diploid cells are produced by an embryonic germ cell? A) Spermatid. B) Polar body. C) Spermatogonia. D) Ovum.
C
Which of the following is an accurate statement concerning mating behavior in asexually reproducing species? A) Mating behavior occurs only in asexually reproducing species during encounters with sexually reproducing species. B) Mating behavior is maladaptive in asexually reproducing species. C) Mating behavior is a stimulus that can help to bring about ovulation in asexually reproducing species. D) Mating behavior occurs only in sexually reproducing species. E) Mating behavior was the first stage in the evolution of sexual reproduction.
C
Which of the following statements about oogenesis in humans is true? A) Oogonia can reproduce mitotically within an adult female ovary to produce more oogonia, which differentiate into primary oocytes. B) Oogenesis takes place within the oviduct. C) Beginning at puberty, a primary oocyte completes its first meiotic division to form a secondary oocyte and a polar body approximately every month. D) The ooctye released from the ovary during ovulation is fully mature.
C
Which reproductive method is the most prevalent in mammals? A) Regeneration B) Fragmentation C) Internal fertilization D) Budding E) External fertilization
C
Pheromones
Chemical messengers released into environment that affect behavior/physiology of other organisms
Cloaca
Common passage for urinary and fecal waste, as well as reproductive system
Individuals clustered in the same area that release their gametes into the water at the same time are engaging in __________. A) budding B) parthenogenesis C) courtship D) spawning E) none of the listed responses is correct
D
The "reproductive handicap" for sexual reproduction refers to _____. A) the need for maturation prior to reproduction B) the need to provide energy for the offspring C) the difficulty of finding mates D) have only half the offspring are females E) dependence on hormonal cycles
D
Vestibular (Bartholin's) glands __________. A) secrete progesterone and estrogen to maintain pregnancy B) partly cover the vagina before sexual intercourse C) contain spongy tissue that fills with blood during arousal D) secrete lubricating fluid E) produce secretions that contribute to semen
D
Which of the following is the correct sequence of stages in the development of sperm during the process of spermatogenesis? A) Primary spermatocyte; secondary spermatocyte; early spermatid; spermatogonial stem cell; spermatogonium; sperm cell B) Early spermatid; primary spermatocyte; spermatogonium; secondary spermatocyte; spermatogonial stem cell; sperm cell C) Primary spermatocyte; secondary spermatocyte; spermatogonial stem cell; spermatogonium; early spermatid; sperm cell D) Spermatogonial stem cell; spermatogonium; primary spermatocyte; secondary spermatocyte; early spermatid; sperm cell E) Early spermatid; spermatogonial stem cell; primary spermatocyte; spermatogonium; secondary spermatocyte; sperm cell
D
Environmental cues that can spark reproduction
Day length, temperature, rainfall, lunar cycles, behavior of other individuals, food supply
When does movement of sperm begin?
During arousal - gather in ejaculatory duct
Seasonal changes can be important to reproduction because ___________. A) environmental stresses that could affect offspring survival can vary with season B) availability of resources on which young can feed can vary with season C) migration and other seasonal movement patterns can affect the possibility of finding a mate D) availability of resources to invest in gestating offspring can vary with season E) All of the listed responses are correct.
E
Sperm become capable of movement while in the _____. A) seminiferous tubules B) vas deferens C) ejaculatory ducts D) urethra E) epididymis
E
The "two-fold" cost of sex refers to ___________. A) the additional cost of parental care B) the necessity of retaining genes for the production of both eggs and sperm C) the energetic requirements of intercourse D) the difficulty of finding a mate E) the lower number of reproductive offspring produced by individuals of species that have two sexes
E
Which of the following is the correct path that sperm travel when leaving the body of a human male? A) Epididymis; seminiferous tubule; ejaculatory duct; urethra; vas deferens B) Epididymis; seminiferous tubule; vas deferens; ejaculatory duct; urethra C) Urethra; vas deferens; epididymis; seminiferous tubule; ejaculatory duct D) Seminiferous tubule; ejaculatory duct; urethra; vas deferens; epididymis E) Seminiferous tubule; epididymis; vas deferens; ejaculatory duct; urethra
E
Hermaphroditism
Each individual can produce both male and female gametes; can sometimes self-fertilize; everyone can hook up with everyone
Parthenogenesis
Egg develops, but individual can develop without fertilization - can be haploid or diploid; all organisms are female (whiptail lizards)
Vulva
External structures of female reproductive system
Spermatheca
Extra holding area for sperm in bees; can store sperm for a year or more; family planning under female control - Sperm released when environmental conditions are favorable
External Fertilization
Female releases egg into environment, then male fertilizes it; requires moist environment - egg usually covered in gelatinous mass
Gamete/Zygote Production in Internal Fertilization
Fewer gametes, higher percent zygote survival
Rugae
Folded muscle in vaginal canal that allows for stretching and pleasure male
Flatworm Reproduction
Hermaphrodites; similar to humans
Why reproduce sexually?
Increased number of offspring that survive over generations, recombines genes in population - produces new ones too, can help remove harmful genes
Sex Reversal
Individuals can change from one gender to another under right environmental cues
Endometrium
Inner lining of cells in uterus; where the zygote implants
Gamete/Zygote Production in External Fertilization
Many gametes, lower percent zygote survival
Who has a cloaca?
Many non-mammalian vertebrates - fish, birds, reptiles
Myometrium
Middle muscle layer of uterus
Budding
New individuals arise from outgrowths on existing ones (hydra)
Vaginal Orifice
Opening of vaginal canal to outside world; in young women, covered by hymen
Perimetrium
Outer connective tissue layer of uterus
Where does the zygote form?
Oviduct
Fission
Parent splits into two individuals (sea anemones)
Baculum
Penis bone in rodents, raccoons, walruses, and whales - Tissues don't have to fill with blood
Why reproduce asexually?
Preserves genes in populations, increased total number of offspring over generations
Benefits of Internal Fertilization
Protects against harsh environmental conditions/physical damage
Coitus
Sperm ejaculated into vaginal canal near cervix; must swim through cervix into uterus/oviduct (guided by mucin)
Vaginal Canal/Vagina
Thick muscular tube of muscle between uterus and outside world; contains rugae; site of sperm deposition during coitus
Orgasm in Females
Uterine and vaginal canal's smooth muscles contract rhythmically
What lubricant does the vaginal wall release during sexual arousal?
Vaginal transudate
Ovulation
When egg cell, surrounded by support cells, is pushed out of ovary
When is asexual reproduction preferred?
When the environment is stable and the organism is well suited to that environment
When is sexual reproduction preferred?
When the environment is unstable
Cervix
Which muscular neck of uterus; opens into vaginal canal