Trait selection in flowering plants: how does sexual selection
... selection is selection that arises from differences in mating success (number of mates that bear or sire progeny over some standardized time interval).” The first part of this definition seems straightforward. However, the parenthetical part can be problematic for those who study organisms with exte ...
... selection is selection that arises from differences in mating success (number of mates that bear or sire progeny over some standardized time interval).” The first part of this definition seems straightforward. However, the parenthetical part can be problematic for those who study organisms with exte ...
Reproductive Ecology of the Green Treefrog (Hyla cinerea) in Northwestern Florida
... Innovation Pond, 1.4 ha) were suburban ponds surrounded by mowed grass, trees and shnibs, with relatively sparse emergent aquatic vegetation. The fourth locality, Megginnis Arm, is an 8 ha portion of Lake Jackson (1620 ha) characterized hy abundant emergent and floating aquatic vegetation and thick ...
... Innovation Pond, 1.4 ha) were suburban ponds surrounded by mowed grass, trees and shnibs, with relatively sparse emergent aquatic vegetation. The fourth locality, Megginnis Arm, is an 8 ha portion of Lake Jackson (1620 ha) characterized hy abundant emergent and floating aquatic vegetation and thick ...
Influence of Body Size and Population Density on
... male size and density. One set of replicates (3 male sizes X 3 male densities) was attempted each day. Arenas, in the above experiment, were 1 m2 at low density and 0.25 m2 for medium and high density treatments (i.e., 1 urchin per arena at low density, 1 and 4 urchins per arena at medium and high d ...
... male size and density. One set of replicates (3 male sizes X 3 male densities) was attempted each day. Arenas, in the above experiment, were 1 m2 at low density and 0.25 m2 for medium and high density treatments (i.e., 1 urchin per arena at low density, 1 and 4 urchins per arena at medium and high d ...
Cells The Basic Unit of Life
... called the _______________. The sperm travel to the urethra through a long tube called the _______________. During this passage, _______________, secreted by the _______________, _______________ and Cowper’s glands are mixed with the sperm. This mixture is called _______________. During sexual inter ...
... called the _______________. The sperm travel to the urethra through a long tube called the _______________. During this passage, _______________, secreted by the _______________, _______________ and Cowper’s glands are mixed with the sperm. This mixture is called _______________. During sexual inter ...
Document
... common form Produces offspring from union of gametes from two genetically different parents Generally, individuals are male or female Organisms are dioecious ...
... common form Produces offspring from union of gametes from two genetically different parents Generally, individuals are male or female Organisms are dioecious ...
www.bio-protocol.org/e2074 Electro
... [Abstract] Electro-fusion system with isolated gametes has been utilized to dissect fertilization-induced events in angiosperms, such as egg activation, zygote development and early embryogenesis, since the female gametophytes of plants are deeply embedded within ovaries. In this protocol, procedure ...
... [Abstract] Electro-fusion system with isolated gametes has been utilized to dissect fertilization-induced events in angiosperms, such as egg activation, zygote development and early embryogenesis, since the female gametophytes of plants are deeply embedded within ovaries. In this protocol, procedure ...
Reproduction in Organisms
... Q. 2. Which is a better mode of reproduction: sexual or asexual? Why? Ans. Sexual reproduction is considered a better mode as it gives rise to genetic variation. (i) This genetic variation may confer some survival advantages on the offspring, under stressful environmental conditions. (ii) It ...
... Q. 2. Which is a better mode of reproduction: sexual or asexual? Why? Ans. Sexual reproduction is considered a better mode as it gives rise to genetic variation. (i) This genetic variation may confer some survival advantages on the offspring, under stressful environmental conditions. (ii) It ...
Oviparity or viviparity? That is the question…
... nutrition to offspring should be favored by natural selection due to the consequent increase in the offspring’s fitness [4,5], but retaining the zygotes and early embryos within the female’s body is a strategy whereby numerous animals protect their offspring during the most vulnerable stage of their ...
... nutrition to offspring should be favored by natural selection due to the consequent increase in the offspring’s fitness [4,5], but retaining the zygotes and early embryos within the female’s body is a strategy whereby numerous animals protect their offspring during the most vulnerable stage of their ...
REPRODUCTION Reproduction is a process of production of new
... After the menstrual stage ( menstration) lasts from first 4 to 5 days, the pituitary gland secretes a hormene, FSH ( follicle stimulating hormone). It stimulates the ovaries to develop an egg and to release certain hormones. The various hormones released during the menstrual cycle and the changes ta ...
... After the menstrual stage ( menstration) lasts from first 4 to 5 days, the pituitary gland secretes a hormene, FSH ( follicle stimulating hormone). It stimulates the ovaries to develop an egg and to release certain hormones. The various hormones released during the menstrual cycle and the changes ta ...
Avoiding bad genes: oxidatively damaged DNA in germ
... damage to sperm DNA. Postcopulatory choice Sexual selection may not only act through behaviours leading to differential copulation with the preferred mate, but also across postcopulatory mechanisms after mating with several mates.(68) In that scenario, females should choose among sperm from differen ...
... damage to sperm DNA. Postcopulatory choice Sexual selection may not only act through behaviours leading to differential copulation with the preferred mate, but also across postcopulatory mechanisms after mating with several mates.(68) In that scenario, females should choose among sperm from differen ...
Lecture: Reproductive Physiology
... mitochondria - located around the base of the tail; provide ATP for the swimming motion cytoplasm - excess cytoplasm in "sloughed off" ...
... mitochondria - located around the base of the tail; provide ATP for the swimming motion cytoplasm - excess cytoplasm in "sloughed off" ...
VERTEBRATES Vertebrates are members of the larger phylum
... flightless). Birds have a characteristic covering of feathers and reproduce by laying eggs. Not all flying animals are birds; and not all birds can fly. The ability to fly has developed independently many times throughout the history of the Earth. Bats (flying mammals), pterosaurs (flying reptiles f ...
... flightless). Birds have a characteristic covering of feathers and reproduce by laying eggs. Not all flying animals are birds; and not all birds can fly. The ability to fly has developed independently many times throughout the history of the Earth. Bats (flying mammals), pterosaurs (flying reptiles f ...
what determines sex roles in mate searching?
... spend considerable amounts of energy moving between harems before mating (Byers et al. 2005). Finally, there are also cases where both sexes invest in mate-finding traits. In many arthropods, for example, females produce pheromones, and males follow these chemical trails (Greenfield 1981; Cardé and ...
... spend considerable amounts of energy moving between harems before mating (Byers et al. 2005). Finally, there are also cases where both sexes invest in mate-finding traits. In many arthropods, for example, females produce pheromones, and males follow these chemical trails (Greenfield 1981; Cardé and ...
REPRODUCTION: THE CONTINUITY OF LIFE
... Pollination brings together the gametes of a flower and it occurs when a pollen grain of the right kind lands on the stigma of the pistil. Each pollen forms a tube that grows down through the pistil and reaches the ovule in the ovary. One of the nuclei in the pollen tube unites with the egg nucleus ...
... Pollination brings together the gametes of a flower and it occurs when a pollen grain of the right kind lands on the stigma of the pistil. Each pollen forms a tube that grows down through the pistil and reaches the ovule in the ovary. One of the nuclei in the pollen tube unites with the egg nucleus ...
1 Assignment Discovery Online Curriculum Lesson title: In Vitro
... both; blocked fallopian tubes; low sperm count; scars in the uterus caused by a condition called endometriosis; or age. Sometimes doctors cannot determine the cause of the infertility. 3. Discuss the options an infertile couple has. Explain that over the last 25 years, physicians have developed in v ...
... both; blocked fallopian tubes; low sperm count; scars in the uterus caused by a condition called endometriosis; or age. Sometimes doctors cannot determine the cause of the infertility. 3. Discuss the options an infertile couple has. Explain that over the last 25 years, physicians have developed in v ...
Mate choice inside an egg cell.
... and defensive characteristics, while intersexual selection usually results in the evolution of exaggerated sexual ...
... and defensive characteristics, while intersexual selection usually results in the evolution of exaggerated sexual ...
Biology 20 Laboratory Quiz Quiz # Animal Reproduction – Take
... B) Peristalsis of ovarian muscles moves the egg into the oviduct. C) The egg is drawn into the oviduct by the action of beating cilia located in the opening of the oviduct. D) The force of the follicular ejection propels the egg into the oviduct. E) The egg propels itself into the oviduct by the bea ...
... B) Peristalsis of ovarian muscles moves the egg into the oviduct. C) The egg is drawn into the oviduct by the action of beating cilia located in the opening of the oviduct. D) The force of the follicular ejection propels the egg into the oviduct. E) The egg propels itself into the oviduct by the bea ...
Chapter 36 Human Reproduction and Development
... Describe how hor–mones help regulate the production of sperm and egg cells. Summarize the structures of the male and female reproductive sys–tems and their functions. Describe the origin and impor–tance of substances found in semen. ...
... Describe how hor–mones help regulate the production of sperm and egg cells. Summarize the structures of the male and female reproductive sys–tems and their functions. Describe the origin and impor–tance of substances found in semen. ...
Full text in pdf format
... Tropical Station, Seikai National Fisheries Research Institute (24° 34’ N, 123° 16’ E). In the laboratory, the crabs were kept individually in plastic lidded boxes (60 × 39 × 27 cm, length × width × depth) through which freshwater flowed up to 3 cm deep. Crabs were fed an artificial diet of dog food ...
... Tropical Station, Seikai National Fisheries Research Institute (24° 34’ N, 123° 16’ E). In the laboratory, the crabs were kept individually in plastic lidded boxes (60 × 39 × 27 cm, length × width × depth) through which freshwater flowed up to 3 cm deep. Crabs were fed an artificial diet of dog food ...
II - Zoology
... where the individual specimen changes sex after spawning (sex reversa1). For instance, Lates calcarifer are protandrous hermaphrodites, males often change their sex after spawning, though not all females are originally males (Moore, 1979; Davis, 1982). Hermaphroditism probably evolve under condition ...
... where the individual specimen changes sex after spawning (sex reversa1). For instance, Lates calcarifer are protandrous hermaphrodites, males often change their sex after spawning, though not all females are originally males (Moore, 1979; Davis, 1982). Hermaphroditism probably evolve under condition ...
Sperm Concentrations and Egg Fertilization Rates
... tioiis in the iiiduced spawning procedure, which in some cases may have stimulated the release of immature gametes. The rough relatioiiships between sperm density and the number of males suggest that the number of sperm released per male was highly variable. The average concentration of sperm in the ...
... tioiis in the iiiduced spawning procedure, which in some cases may have stimulated the release of immature gametes. The rough relatioiiships between sperm density and the number of males suggest that the number of sperm released per male was highly variable. The average concentration of sperm in the ...
Name
... than their smaller counterparts. Regardless of their size, males that mate frequently will transfer less sperm to each individual female than males that mate less often. A male can fully recharge his sperm stores in about 10 - 20 days. For the females, larger size at maturity can result in larger eg ...
... than their smaller counterparts. Regardless of their size, males that mate frequently will transfer less sperm to each individual female than males that mate less often. A male can fully recharge his sperm stores in about 10 - 20 days. For the females, larger size at maturity can result in larger eg ...
Animal Science - Lehi FFA
... time from fertilization or conception of a female until she gives birth ...
... time from fertilization or conception of a female until she gives birth ...
Anisogamy
Anisogamy (noun) (also called heterogamy) refers to a form of sexual reproduction involving the union or fusion of two dissimilar gametes (differing either in size and/or form) — anisogamous, anisogamic, (adj.). The smaller gamete is considered to be male (sperm cell), whereas the larger gamete is regarded as female (egg cell).There are several types of anisogamy. Both gametes may be flagellated and thus motile. Alternatively, neither of the gametes may be flagellated. This situation occurs for example in some algae and plants. In the red alga Polysiphonia, large non-motile egg cells are fertilized by small, non-motile spermatia. In flowering plants, the gametes are non-motile cells within gametophytes.The form of heterogamy that occurs in animals, including humans, is oogamy. In oogamy, a large, non-motile egg cell (ovum) is fertilized by a small, motile sperm cell (spermatozoon). The large egg cell is optimized for longevity, whereas the small sperm cell is optimized for motility and speed. The size and resources of the egg cell allow for the production of pheromones, which attract the swimming sperm cells.