Short Answer Questions
Solutions for Biology, Class 10, ICSE
Short Answer Questions 2 Marks Each
22 questionsAnswer:
In Dengue fever, the platelet count drops sharply. This leads to coagulation of blood slowly, which can lead to haemorrhage. On other hand, haemophilia is a genetic disorder in which the body's blood clotting process is impaired due to the absence of clotting factors.
Answer:
(a) The rate of photosynthesis gets doubled since it increases with increase in temperature up to the optimum temperature of 35°C.
(b) Photosynthesis stops at 40°C.
Answer:
Atomic explosion leads to radiation exposure. This radiation exposure leads to change in DNA i.e. mutation. Such mutations are responsible for a large number of persisting deformities in the bodies of plants and animals.
Answer:
No, the foetus will not be infected because the placenta does not allow the passage of germs from the mother to the foetus. There is no mixing of blood between mother and foetus.
Answer:
Genotype | Phenotype |
---|---|
Set of genes present in any organism is known as its genotype. | Characters expressed or physical appearance of characters is called phenotype. |
Can be determined by genotyping method. | Can be determined by observation. |
It is formed by expressed and unexpressed genes. | It consists of only expressed genes. |
Answer:
During winters in metropolitan cities like Delhi, the fog and smoke together form smog. Inhalation of smog causes rise in patients of asthma.
It can be reduced by:
- Installation of tall chimneys in factories with filters.
- Electrostatic precipitators.
Answer:
In our country, the infant mortality rate is high specially in rural areas or weaker section but the population keeps on rising because people of weaker section think it safer to produce more children so that at least some may survive.
Answer:
The vermiform appendix projects from the blind end of the caecum in humans. It is called a vestigial organ because it no longer has a vital function for us. It might have been useful to our ancestors for digesting tough plant materials, but now it serves little purpose.
Answer:
Adrenal virilism is a condition that results from excessive production of androgens (male hormones) by the adrenal glands. It leads to the development of male physical characteristics in females like the development of a beard, moustache and deep voice. It is caused by overgrowth of the adrenal cortex in a mature woman.
Answer:
(a) They are identical twins.
(b) Identical twins (monozygotic twins), are always of the same gender because they originate from a single fertilized egg (zygote). Their gender is decided at the time of fertilization.
Answer:
Albumin may be passed out in urine under following conditions:
- due to high blood pressure
- due to increased permeability of the bowman’s capsule membrane on account of bacterial infection
This condition is known as Albuminuria.
Answer:
Testes are responsible for the production of male gametes i.e., sperms. The normal body temperature does not allow the maturation of the sperms. Being suspended outside the body cavity, the temperature in the scrotal sac is 2 to 3°C lower than that of the body which is the suitable temperature for the maturation of the sperms.
Answer:
Rhodopsin is the pigment which is responsible for vision in dim lights. It gets bleached in bright light. It takes a few seconds for it to regenerate in dim light. Then, the vision improves. Iodopsin responsible for vision in bright light does not function in dim light.
Answer:
Due to deficiency of oxygen in the room, the burning furnace will emit carbon monoxide. This carbon monoxide when inhaled, combines with oxygen to form a stable compound, Carboxyhaemoglobin, which cuts off the supply of oxygen to tissues, leading to death due to asphyxiation.