INSECT

REPRODUCTIVE

SYSTEM

Reproductive system

(1) of mixed embryonic origin - ecto- & mesoderm

(2) only functional in adult

(3) not required for survival of individual

(4) contributes directly to next generation

Insect Reproductive System

gonad

Primary exit system

Secondary exit system

gonopore

Mesodermal

Ectodermal

Female Reproductive System

ovariole

lateral oviduct

common oviduct

vagina

accessory gland

spermathecal gland

spermatheca

ovary

calyx

Ovarioles

terminal filament

Germarium (2N)

Vitellarium (N)

Types of Ovarioles

Ovarioles1. Dieroistic2. Panoistic 3. Meroistic

a. Polytrophicb. Telotrophic (Acrotrophic)1. Dieroistic

common sac

primary oocyte

follicle cells

Lateral oviduct

Types of Ovarioles

Ovarioles1. Dieroistic2. Panoistic 3. Meroistic

a. Polytrophicb. Telotrophic (Acrotrophic)2. Panoistic

primary oocyte

follicle cells

germinal vesicle(nucleus)

peritoneal sheath

Types of Ovarioles

Ovarioles1. Dieroistic2. Panoistic 3. Meroistic

a. Polytrophicb. Telotrophic (Acrotrophic)2. Meroistic

a. Polytrophic

primary oocyte

follicle cells

germinal vesicle(nucleus)

peritoneal sheath

nurse cells

Types of Ovarioles

Ovarioles1. Dieroistic2. Panoistic 3. Meroistic

a. Polytrophicb. Telotrophic (Acrotrophic)2. Meroistic

a. Polytrophic

Types of Ovarioles

Ovarioles1. Dieroistic2. Panoistic 3. Meroistic

a. Polytrophicb. Telotrophic (Acrotrophic)2. Meroistic

b. Telotrophic

primary oocyte

follicle cells

germinal vesicle(nucleus)

peritoneal sheath

nurse cells

trophic cord

Male Reproductive System

testis

Ejaculatory duct

follicle

accessory gland

vas deferensseminal vesicle

Male Reproductive Systemapical

cell

Germarium

Zone of Growth

Zone of Maturation

Zone of Transformation

2N

N

Accessory gland products - Spermatophore

GametogenesisGametogenesis - all gametogenesis follows the same general sequence

Germ cell

Mitosis to produce more germ cells

2N

2N Primary gametocyte(meiosis I prophase)

N N

Complete meiosis I

Secondary gametocyte

N N N N

Meiosis II

Gamete

Onset of meiosis I

SpermatogenesisSpermatogonium

Mitosis to produce more germ cells

2N

2N Primary spermatocyte(meiosis I prophase)

N N

Complete meiosis I

Secondary spermatocyte

N N N N

Meiosis II

Early spermatids

Onset of meiosis I

Spermatozoa

Differentiation

Spermatogenesis

2N

2N

N N

N N N N

Germarium

Zone of Growth

Zone of Maturation

Zone of Transformation

Structure of Sperm – Mammalian model

acrosome

actin nucleus mitochondria

tail

Sperm types

ApyreneEupyrene

Sperm types

Oogenesis

Oogonium

Mitosis to produce more germ cells

2N

2N Primary oocyte(meiosis I prophase - arrested - present at birth)

N

Complete meiosis I

Secondary oocyte(arrested at metaphase of meiosis II)

N Ovum

Onset of meiosis I

Ovulation

First polar body

Second polar body

Germarium (2N)

Vitellarium (N)

Structure of ovariole

Vitellogenesis

Choriogenesis