Write shorts note on.
1) Lymph.
2) Blood pressure (BP).
3) Homologous and Analogous Organs.
4) Sex determination.
5) Mendal contribution.
Answers
Answer:
1) Lymph is a fluid which flows through the lymphatic system of the body and takes part in transportation. Lymph is formed by the seepage of blood plasma, proteins and few blood cells through the pores of capillaries. This fluid transports protein, fats and other nutrients from the digestive system.
2) Blood pressure (BP) is the pressure of circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term "blood pressure" refers to the pressure in the large arteries.
3) Homologous organs are those organs which have the same basic structural design and origin but have different functions.
For example: The forelimbs of humans and the wings of birds look different externally but their skeletal structure is similar.
Analogous organs are those organs which have the different basic structural design and origin but have similar functions.
For example: The wings of birds and insects.
4) ex determination in humans is XX-XY type. Apart from humans, XX-XY system of sex determination is found in most mammals and some insects. In humans, there are total 46 chromosomes. Out of these 46 chromosomes, 44 are autonomies and 2 are sex chromosomes. The sex chromosomes are X and Y. Both X and Y chromosomes are different in size and shapes. They also carry different sets of genes. Females have two same chromosomes (XX) whereas males have two different sex chromosomes (XY). Hence, females have 44 + XX chromosomes and males have 44 + XY chromosomes. During gamete formation, female produces only one type of gamete 22 + X. Whereas, male produces two types of gametes, namely 22 + X and 22 + Y.
5) Gregor Mendel, through his work on pea plants, discovered the fundamental laws of inheritance. He deduced that genes come in pairs and are inherited as distinct units, one from each parent. Mendel tracked the segregation of parental genes and their appearance in the offspring as dominant or recessive traits. He recognized the mathematical patterns of inheritance from one generation to the next.