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?
Can you think of reasons why more complex organisms cannot give rise to new individuals through regeneration?
Asexual reproduction takes place through budding in
(a) amoeba.
(b) yeast.
(c) plasmodium.
(d) leishmania.
What are the advantages of sexual reproduction over asexual reproduction?
How does the embryo get nourishment inside the mother’s body?
How does reproduction help in providing stability to populations of species?
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 is sodium kept immersed in kerosene oil?
Write a balanced chemical equation with state symbols for the following reactions:
Which sources produce alternating current?
What are the necessary conditions for autotrophic nutrition and what are its by-products?
Compare and contrast bio-mass and hydro electricity as sources of energy.
An object 5 cm in length is held 25 cm away from a converging lens of focal length 10 cm. Draw the ray diagram and find the position, size and the nature of the image formed.
Why do we prefer a convex mirror as a rear-view mirror in vehicles?
Name a mirror that can give an erect and enlarged image of an object.
The radius of curvature of a spherical mirror is 20 cm. What is its focal length?
Define the principal focus of a concave mirror.