What is the role of the seminal vesicles and the prostate gland?
Seminal vesicles and prostate gland both are the accessory sex glands in male reproduction system.seminal vesicle secrete fluid that consist of nutrientsthat support sperm until fertilisation occurs.
Seminal vesicles contains hormone called prostaglandins, which stimulate contraction in the female reproductive system for the transportation of sperms to the oviduct with ovum.
Prostate gland secretes thin, milky and acidic fluid which is discharged into the part of urethra. It also contains sperms nutrient and some anticoagulant enzymes. Their secretion activates the sperms to swim fluently.
Why is variation beneficial to the species but not necessarily for the individual?
Draw a labelled diagram of the longitudinal section of a flower.
What are the functions performed by the testis in human beings?
Why does menstruation occur?
How will an organism be benefited if it reproduces through spores?
Asexual reproduction takes place through budding in
(a) amoeba.
(b) yeast.
(c) plasmodium.
(d) leishmania.
Can you think of reasons why more complex organisms cannot give rise to new individuals through regeneration?
How does the embryo get nourishment inside the mother’s body?
What are the advantages of sexual reproduction over asexual reproduction?
What is the importance of DNA copying in reproduction?
Did Döbereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.
What is a good source of energy?
Why is diffusion insufficient to meet the oxygen requirements of multi-cellular organisms like humans?
What are trophic levels? Give an example of a food chain and state the different trophic levels in it.
What changes can you make in your habits to become more environment-friendly?
What is the difference between a reflex action and walking?
If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?
Why should a magnesium ribbon be cleared before burning in air?
Define the principal focus of a concave mirror.
You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?
Why do you think the noble gases are placed in a separate group?
Why do HCl, HNO3, etc., show acidic characters in aqueous solutions while solutions of compounds like alcohol and glucose do not show acidic character?
When a 12 V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit. Find the value of the resistance of the resistor.
Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal?
Let the resistance of an electrical component remains constant while the potential difference across the two ends of the component decreases to half of its former value. What change will occur in the current through it?
What is the difference between displacement and double displacement reactions? Write equations for these reactions.
The device used for producing electric current is called a
(a) generator.
(b) galvanometer.
(c) ammeter.
(d) motor.
Why are some patients of diabetes treated by giving injections of insulin?
Give reasons why copper is used to make hot water tanks and not steel (an alloy of iron).
What is the role of the brain in reflex action?