Tag: modes of reproduction
Questions Related to modes of reproduction
Monoestrus animals have
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One ovulation each month
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One egg
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One breeding season in a year
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One menses each month
Estrus cycle is indication of
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Breeding period
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Estrogen secretion
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Pregnancy
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Menopause
Estrus cycle is the indication of the breeding period because it is a reproductive cycle of females of non-primate vertebrates and it is the period in which the female is highly receptive. One or more periods of estrus may occur during the breeding season of a species. Some animals like dogs are monoestrous as they have only one oestrous phase in their breeding cycle. Males can recognize a female in heat by the smell of pheromones.
What would be the number of chromosomes in the aleuronic cells of a plant with $42$ chromosomes in the root tip cells?
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$21$
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$42$
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$63$
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$84$
Which of the following cannot be seen during estrus cycle?
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Estrogen produces strong sex surge
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Menstruation at the end of the estrous cycle
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Ovulation takes place during estrus phase
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None of the above
- Animals that have estrus cycles resorb the endometrium if conception does not occur during that cycle.
- Animals that have menstrual cycles shed the endometrium through menstruation if conception does not take place.
- So, the correct option is 'Menstruation at the end of the estrus cycle'.
Which of the following statement is true?
A) Sexual receptivity occurs all through the menstrual cycle.
B) Estrus prepares the female reproductive tract for copulation.
C) The hypertrophic lining is sloughed off as menstrual flow.
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Only A
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Both A and B
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Both A and C
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Both B and C
Sexual receptivity is the stage when the female accepts the sperms for fertilization during the process of intercourse. The female becomes sexually receptive during the estrus phase of the menstrual cycle.
Which of the following statement can be related to metestrus phase of an estrus cycle?
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The hypertrophy of glands of uterine mucosa
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Corpus luteum develops
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In absence of fertilisation the corpus luteum degenerates
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All of the above
- Metestrus phase is characterized by the activity of the corpus luteum, which produces progesterone.
- The uterine lining begins to appear and hypertrophy of glands is observed due to increased progesterone.
- Just like menstrual cycle, absence of fertilisation leads to degeneration of corpus luteum in estrus cycle.
- So, the correct option is 'All of the above'.
The estrus frequency of cow is
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18 days
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15 days
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21 days
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!7 days
- Estrus cycle is the period of sexual activity in female mammals except for higher mammals, during which they are in heat i.e. ready to mate.
- Cows can go into heat several times per year.
- Estrus frequency of cow is 21 days i.e. it goes into heat with a duration of 21 days.
- So, the correct option is '21 days'.
Proestrus bleeding in dogs is caused due to
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Increase of the estradiol-17 hormone
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Inflammatory response of WBC
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Ovulation
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All of the above
The reproductive cycle of the non primate females is called estrous cycle. It can be divided into four phases: proestrus, estrus, metestrus and diestrus. Proestrus stage is the building up phase. There is bleeding found in dogs during the proestrus phase. There is increase in the level of estradiol-17 hormone. This results in the movement or diapedesis of the red blood cells in the blood vessels which causes bleeding.
The female cat stays in heat for
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18-21 days
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16-21 days
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14-21 days
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None of the above
- Estrus is the period in the sexual cycle of female mammals, except the higher primates, during which they are in heat—i.e., ready to accept a male and to mate.
- The female cat stays in heat for 14-21 days i.e. it is ready to mate for this duration.
- So, the correct option is '14-21 days'.
A difference between estrous and menstrual cycles is that
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Non-mammalian vertebrates have estrous cycles, whereas mammals have menstrual cycles
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The endometrial lining is shed in menstrual cycles but reabsorbed in estrous cycles
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Estrous cycles occur more frequently than menstrual cycles do
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Ovulation occurs before the endometrium thickens in estrous cycles
Menstrual cycle occurs in primates (monkeys, apes and human beings). This cycle consists of the menstrual phase, the proliferative phase and the secretory phase and the broken endometrium is passed out during menstruation. The oestrous cycle occurs in non-primates such as cows, dogs, etc. It consists of a short period of estrus or heat followed by anoestrus or passive period. The broken endometrium is reabsorbed during the oestrous cycle.