Week 1 Objectives 6: Compare spermatogenesis with oogenesis, summarize major steps in spermiogenesis

Question 1

Spermatogonia

Answer 1

2N Type A (stem cells) Type B: Leave mitotic cycle and enter meiotic cycle under influence of retinoic acid

Question 1

Primary Spermatocytes

Answer 1

Undergoes Meiosis I —> Secondary Spermatocytes

Question 1

Hyalurodinase

Answer 1

acrosomal enzyme

Question 2

Spermiogenesis (SECOND TWO)

Answer 2

Acrosomal Phase 1. rotation of acrosomal pole toward wall of seminiferous tubule 2. Cytoplasm displaced toward tail Maturation phase 1. completion of flagellum 2. completion of nuclear condensation

Question 3

Spermiogenesis (FIRST TWO)

Answer 3

1. Golgi phase a. Proacrosomal vesciles b. acrosomal vesciles 2. Cap phase a. mature acrosomes form cap over nucleus

Question 4

Structure of the Testis

Answer 4

Primitive sex cords Seminiferous tubules 1. Spermatagonia cells 2. Sertoli cells Cells of Leydig (interstital cells) 1. Produce testosterone

Question 5

Zona lysin

Answer 5

acrosomal enzymes (in mammalian sperm)

Question 7

Primordial Germ Cells

Answer 7

diploid (2N)

Question 9

Sequence of cell types, meiotic events, and chromosomal complement in spermatogenesis

Answer 9

1. Spermatogonium: 2n, 4c —> I I V 2. Primary Spermatocyte —> 2n, 4C Meiosis 3. Two haploid Secondary Spermatocytes —> n, 2C Meiosis II 4. Four haploid Spermatids —> n, 1c I V Spermiogenesis —> Spermatazoa (4 haploid gametes)

Question 10

Spermatids

Answer 10

4 haploid cells

Question 11

Spermiogenesis: acrosomal enzymes

Answer 11

synthesized under influence of mRNA during pre-leptotene stage

Question 12

Sperm histones

Answer 12

proamines

Question 13

Secondary Spermatocytes

Answer 13

haploid, 2 cells, begins meiosis II