Fill in the blanks : (a) ___ consists of membranous sacs and secretes 40 types of digestive enzymes. (b) ___ is surrounded by microtubules, located near the nucleus. (c) Very thin flexible, living membrane which is differentially permeable, is called ___ (d) More than 1000 chromosomes are found in the nucleus of certain ___ (e) ___ are hereditary units. (f) ___ is a plastid which stores starch.
Chromosomes are present inside the nucleus of cells. There are ___________ pairs of chromosomes found in human beings. A pair of corresponding chromosomes of the same size and shape is called a __________________ pair. In the pair both parents contribute one chromosome. Haploid cells have only ______________ the chromosomes of diploid cells. If an organism has more than a pair of homologous chromosomes, the organism is said to be ______________________________. E.g.: ____________________________. The number of chromosomes varies from organisms to organisms.