Question

A bivalent consists of

(a) Two chromatids and one centromere

(b) Two chromatids and two centromeres

(c) Two chromatids and two centromeres

(d) Four chromatids and four centromeres

Answer 1

Correct option  (c) Two chromatids and two centromeres

Explanation :

Each pair of homologous chromosome carrying one maternal and one paternal chromosome of similar type is called bivalent. Each chromosome has two sister chromatids and a centromere. Thus. bivalent possesses four chromatids, two centromeres. This bivalent with four chromatids is called pachytene tetrad (quadrivalent).