How many eggs are released by a human ovary in a month? How many
Question: How many eggs are released by a human ovary in a month? How many eggs do you think would have been released if the mother gave birth to identical twins? Would your answer change if the twins born were fraternal? Solution: An ovary releases an egg every month. When two babies are produced in succession, they are called twins. Generally, twins are produced from a single egg by the separation of early blastomeres resulting from the first zygotic cleavage. As a result, the young ones forme...
Read More →The perpendicular from the origin to a line meets it at the point (– 2, 9),
Question: The perpendicular from the origin to a line meets it at the point ( 2, 9),find the equation of the line. Solution: The slope of the line joining the origin $(0,0)$ and point $(-2,9)$ is $m_{1}=\frac{9-0}{-2-0}=-\frac{9}{2}$ Accordingly, the slope of the line perpendicular to the line joining the origin and point ( 2, 9) is $m_{2}=-\frac{1}{m_{1}}=-\frac{1}{\left(-\frac{9}{2}\right)}=\frac{2}{9}$ Now, the equation of the line passing through point $(-2,9)$ and having a slope $m_{2}$ is ...
Read More →In our society the women are often blamed for giving birth to daughters.
Question: In our society the women are often blamed for giving birth to daughters. Can you explain why this is not correct? Solution: All human beings have 23 pairs of chromosomes. Human males have 22 pairs of autosomes and contain one or two types of sex chromosome. They are either X or Y. On the contrary, human females have 22 pairs of autosomes and contain only the X sex chromosome. The sex of an individual is determined by the type of the male gamete (X or Y), which fuses with the X chromoso...
Read More →What is parturition? Which hormones are involved in induction of parturition?
Question: What is parturition? Which hormones are involved in induction of parturition? Solution: Parturition is the process of giving birth to a baby as the development of the foetus gets completed in the mothers womb. The hormones involved in this process are oxytocin and relaxin. Oxytocin leads to the contraction of smooth muscles of myometrium of the uterus, which directs the full term foetus towards the birth canal. On the other hand, relaxin hormone causes relaxation of the pelvic ligament...
Read More →What is menstrual cycle? Which hormones regulate menstrual cycle?
Question: What is menstrual cycle? Which hormones regulate menstrual cycle? Solution: The menstrual cycle is a series of cyclic physiologic changes that take place inside the female reproductive tract in primates. The whole cycle takes around 28 days to complete. The end of the cycle is accompanied by the breakdown of uterine endothelium, which gets released in the form of blood and mucous through the vagina. This is known as menses. The follicle stimulating hormone (FSH), luteinizing hormone (L...
Read More →Find equation of the line through the point (0, 2) making an angle
Question: Find equation of the line through the point $(0,2)$ making an angle $\frac{2 \pi}{3}$ with the positive $x$-axis. Also, find the equation of line parallel to it and crossing the $y$-axis at a distance of 2 units below the origin. Solution: The slope of the line making an angle $\frac{2 \pi}{3}$ with the positive $x$-axis is $m=\tan \left(\frac{2 \pi}{3}\right)=-\sqrt{3}$ Now, the equation of the line passing through point $(0,2)$ and having a slope $-\sqrt{3}$ is $(y-2)=-\sqrt{3}(x-0)$...
Read More →Identify True/False statements. Correct each false statement to make it true.
Question: Identify True/False statements. Correct each false statement to make it true. (a)Androgens are produced by Sertoli cells. (True/False) (b)Spermatozoa get nutrition from Sertoli cells. (True/False) (c)Leydig cells are found in ovary. (True/False) (d)Leydig cells synthesise androgens. (True/False) (e)Oogenesis takes place in corpus luteum. (True/False) (f)Menstrual cycle ceases during pregnancy. (True/False) (g)Presence or absence of hymen is not a reliable indicator of virginity or sexu...
Read More →Name the functions of the following.
Question: Name the functions of the following. (a)Corpus luteum (b)Endometrium (c)Acrosome (d)Sperm tail (e)Fimbriae Solution: (a)Corpus luteum Corpus luteum is formed from the ruptured Grafiaan follicle. It secretes progesterone hormone during the luteal phase of the menstrual cycle. A high level of progesterone inhibits the secretions of FSH and LH, thereby preventing ovulation. It also allows the endometrium of the uterus to proliferate and to prepare itself for implantation. (b)Endometrium I...
Read More →Find equation of the line passing through the point (2, 2) and
Question: Find equation of the line passing through the point (2, 2) and cutting off intercepts on the axes whose sum is 9. Solution: The equation of a line in the intercept form is $\frac{x}{a}+\frac{y}{b}=1$(i) Here,aandbare the intercepts onxandyaxes respectively. It is given thata $+b=9 \Rightarrow b=9-a \ldots$ (ii) From equations (i) and (ii), we obtain $\frac{x}{a}+\frac{y}{9-a}=1$...(iii) It is given that the line passes through point $(2,2)$. Therefore, equation (iii) reduces to $\frac{...
Read More →Draw a labeled diagram of a Graafian Follicle?
Question: Draw a labeled diagram of a Graafian Follicle? Solution:...
Read More →Draw a labeled diagram of a section through ovary.
Question: Draw a labeled diagram of a section through ovary. Solution:...
Read More →Due to economic reasons, only the upper sideband of an AM wave is transmitted,
Question: Due to economic reasons, only the upper sideband of an AM wave istransmitted, but at the receiving station, there is a facility for generating the carrier. Show that if a device is available which can multiply two signals, then it is possible to recover the modulating signal at the receiver station. Solution: Letcandsbe the respective frequencies of the carrier and signal waves. Signal received at the receiving station,V=V1cos (c+s)t Instantaneous voltage ofthe carrier wave,Vin=Vccosct...
Read More →Find the values of k so that the function f is continuous at the indicated point.
Question: Find the values ofkso that the functionfis continuous at the indicated point. $f(x)=\left\{\begin{array}{ll}k x^{2}, \text { if } x \leq 2 \\ 3, \text { if } x2\end{array} \quad\right.$ at $x=2$ Solution: The given function is $f(x)= \begin{cases}k x^{2}, \text { if } x \leq 2 \\ 3, \text { if } x2\end{cases}$ The given functionfis continuous atx= 2, iffis defined atx= 2 and if the value offatx= 2 equals the limit offatx= 2 It is evident that $f$ is defined at $x=2$ and $f(2)=k(2)^{2}=...
Read More →What is oogenesis? Give a brief account of oogenesis.
Question: What is oogenesis? Give a brief account of oogenesis. Solution: Oogenesis is the process of the formation of a mature ovum from the oogonia in females. It takes place in the ovaries. During oogenesis, a diploid oogonium or egg mother cell increases in size and gets transformed into a diploid primary oocyte. This diploid primary oocyte undergoes first meiotic division i.e., meiosis I or reductional division to form two unequal haploid cells. The smaller cell is known as the first polar ...
Read More →Due to economic reasons, only the upper sideband of an AM wave is transmitted,
Question: Due to economic reasons, only the upper sideband of an AM wave istransmitted, but at the receiving station, there is a facility for generating the carrier. Show that if a device is available which can multiply two signals, then it is possible to recover the modulating signal at the receiver station. Solution: Letcandsbe the respective frequencies of the carrier and signal waves. Signal received at the receiving station,V=V1cos (c+s)t Instantaneous voltage ofthe carrier wave,Vin=Vccosct...
Read More →For an amplitude modulated wave,
Question: For an amplitude modulated wave, the maximum amplitudeis found to be 10 V while the minimum amplitude is found to be 2 V. Determine the modulation index. What would be the value ofif the minimum amplitude is zero volt? Solution: Maximum amplitude,Amax= 10 V Minimum amplitude,Amin= 2 V Modulation index, is given by the relation: $\mu=\frac{A_{\max }-A_{\min }}{A_{\max }+A_{\min }}$ $=\frac{10-2}{10+2}=\frac{8}{12}=0.67$ If $A_{\min }=0$, Then $\mu^{\prime}=\frac{A_{\max }}{A_{\max }}=\f...
Read More →Find the equation of a line that cuts off equal intercepts on the coordinate axes and passes through the point (2, 3).
Question: Find the equation of a line that cuts off equal intercepts on the coordinate axes and passes through the point (2, 3). Solution: The equation of a line in the intercept form is $\frac{x}{a}+\frac{y}{b}=1$$\ldots$ (i) Here,aandbare the intercepts onxandyaxes respectively. It is given that the line cuts off equal intercepts on both the axes. This means thata=b. Accordingly, equation (i) reduces to $\frac{x}{a}+\frac{y}{a}=1$ $\Rightarrow x+y=a$ $\ldots$ (ii) Since the given line passes t...
Read More →A modulating signal is a square wave, as shown in Fig. 15.14.
Question: A modulating signal is a square wave, as shown in Fig. 15.14. The carrier wave is given by $c(t)=2 \sin (8 \pi t)$ volts. (i)Sketch the amplitude modulated waveform (ii)What is the modulation index? Solution: It can be observed from the given modulating signal thatthe amplitude of the modulating signal,Am= 1 V It is given that the carrier wavec(t) = 2 sin (8t) Amplitude of the carrier wave,Ac= 2 V Time period ofthe modulating signalTm= 1 s The angular frequency of the modulating signal...
Read More →What are the major functions of male accessory ducts and glands?
Question: What are the major functions of male accessory ducts and glands? Solution: The male accessory ducts are vasa efferentia, epididymis, vas deferens, and rete testis. They play an important role in the transport and temporary storage of sperms. On the contrary, male accessory glands are seminal vesicles, prostate glands, and bulbourethral glands. These glands secrete fluids that lubricate the reproductive system and sperms. The sperms get dispersed in the fluid which makes their transport...
Read More →Find the values of k so that the function f is continuous at the indicated point.
Question: Find the values ofkso that the functionfis continuous at the indicated point. $f(x)=\left\{\begin{array}{ll}\frac{k \cos x}{\pi-2 x}, \text { if } x \neq \frac{\pi}{2} \\ 3, \text { if } x=\frac{\pi}{2}\end{array} \quad\right.$ at $x=\frac{\pi}{2}$ Solution: The given function $f$ is $f(x)= \begin{cases}\frac{k \cos x}{\pi-2 x}, \text { if } x \neq \frac{\pi}{2} \\ 3, \text { if } x=\frac{\pi}{2}\end{cases}$ The given function $f$ is continuous at $x=\frac{\pi}{2}$, if $f$ is defined a...
Read More →A line perpendicular to the line segment joining the points (1, 0) and (2, 3)
Question: A line perpendicular to the line segment joining the points (1, 0) and (2, 3) divides it in the ratio 1:n. Find the equation of the line. Solution: According to the section formula, the coordinates of the point that divides the line segment joining the points (1, 0) and (2, 3) in the ratio 1:nis given by $\left(\frac{n(1)+1(2)}{1+n}, \frac{n(0)+1(3)}{1+n}\right)=\left(\frac{n+2}{n+1}, \frac{3}{n+1}\right)$ The slope of the line joining the points (1, 0) and (2, 3) is $m=\frac{3-0}{2-1}...
Read More →What are the major components of seminal plasma?
Question: What are the major components of seminal plasma? Solution: Semen (produced in males) is composed of sperms and seminal plasma. The major components of the seminal plasma in the male reproductive system are mucus, spermatozoa, and various secretions of accessory glands. The seminal plasma is rich in fructose, calcium, ascorbic acid, and certain enzymes. It provides nourishment and protection to sperms....
Read More →A carrier wave of peak voltage 12 V is used to transmit a message signal.
Question: A carrier wave of peak voltage 12V is used to transmit a message signal. What should be the peak voltage of the modulating signal in order to have a modulation index of 75%? Solution: Amplitude of the carrier wave,Ac= 12 V Modulation index,m= 75% = 0.75 Amplitude of the modulating wave =Am Using the relationfor modulation index: $m=\frac{A_{\mathrm{m}}}{A_{\mathrm{c}}}$ $\therefore A_{\mathrm{m}}=m A_{\mathrm{c}}$ $=0.75 \times 12=9 \mathrm{~V}$...
Read More →Find the equation of the line passing through (–3, 5)
Question: Find the equation of the line passing through (3, 5) and perpendicular to the line through the points (2, 5) and (3, 6). Solution: The slope of the line joining the points $(2,5)$ and $(-3,6)$ is $m=\frac{6-5}{-3-2}=\frac{1}{-5}$ We know that two non-vertical lines are perpendicular to each other if and only if their slopes are negative reciprocals of each other. Therefore, slope of the line perpendicular to the line through the points $(2,5)$ and $(-3,6)=-\frac{1}{m}=-\frac{1}{\left(\...
Read More →A carrier wave of peak voltage 12 V is used to transmit a message signal.
Question: A carrier wave of peak voltage 12V is used to transmit a message signal. What should be the peak voltage of the modulating signal in order to have a modulation index of 75%? Solution: Amplitude of the carrier wave,Ac= 12 V Modulation index,m= 75% = 0.75 Amplitude of the modulating wave =Am Using the relationfor modulation index:...
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