CASE BASED QUESTIONS-Class 10 -Science-Biology-

Pea plants can have smooth seeds or wrinkled seeds. One of the phenotypes is completely dominant over the other. A farmer decides to pollinate one flower of a plant with smooth seeds using pollen from plant with wrinkled seeds. The resulting pea pod has all smooth seeds.
Q1 Which of the following conclusions can be drawn?
(1) The allele for smooth seeds is dominated over that of wrinkled seeds.
(2) The plant with smooth seeds is heterozygous.
(3) The plant with wrinkled seeds is homozygous.

Q2Which of the following crosses will give smooth and wrinkled seeds in same proportion?

Q3. Which of the following cross can be used to determine the genotype of a plant with dominant phenotype?

Q4. On crossing of two heterozygous smooth seeded plants (Rr), a total of 1000 plants were obtained in F₁
generation. What will be the respective number of smooth and wrinkled seeds obtained in F₁ generation?

 Q5. The characters which appear in the first filial generation are called

The male reproductive system consist of portions which produce the germ-cells and other portions that deliver the germ-cells to the site of fertilisation. Testes are located outside the abdominal cavity in scrotum because sperm formation requires a lower temperature than normal
body temperature. It also has a role of secretion of male sex hormone which brings changes in appearance seen in boys at the time of puberty. Vas deferens unites with a tube coming from urinary bladder. Urethra is a common passage for sperms and urine. Prostate gland and seminal vesicles add their secretions so that sperms are now in fluid.

Q2 Which of the following statements is incorrect ?

Q3. Testes are located outside the abdominal cavity in scrotum because

Q4. Which of the following statement is incorrect?

Q5. What is the nature of semen?

To carry out a simple function such as eating food there has to be coordination of the eyes, hands and the mouth. The eyes have to focus on the food, the hands have to pick it up and take it to the mouth where it will be chewed. All these actions have to be coordinated in such a manner that they follow a particular sequence and the action is completed. A similar mechanism is also needed for internal functions of the body. This function is carried out by the nervous system. It is composed of

(a) Specialised cells which can detect, receive and transmit different kinds of stimuli. These are called neurons.
(b) Nerve fibres which are certain bundles of extended processes of nerve cells.

The individuals also have to adjust to the changing conditions around them and vary their responses. At the same time, the internal conditions of the body should be maintained constant. This is called homeostasis. The internal conditions of the body are maintained at a constant by controlling the physiology of the organisms.

Q1. What will the correct sequence in which conduction of information through nerves take place?

Q2. How homeostasis is said to maintain the equilibrium of the body?

Q3.  What function does the central nervous system perform?

Q4. What happens when the dendrite tip of a nerve cell receives a signal?

There is a range of strategies by which the food is taken in and used by the organisms in heterotrophic nutrition. Some organism breakdown the food material outside the body and then absorb it. Others take in whole material and break it down inside their bodies. What can be taken in and broken down depends on the body design and functioning. Some others derive nutrition from plants and animals without killing them.

Q1. Organisms which derive nutrition from plants and animals without killing them.

 Q2. In which part of amoeba complex food particles are broken down into simpler ones.

Q3. Which of the following is an example of saprotroph.

Q4. Taking in whole material and breaking it down inside the body is

Q5.  Heterotrophic nutrition involves