Reproductive System: Chapter 27

• Chapter 27 is about the reproductive system
• The chapter covers:
• Introduction
• Male reproductive system
• Female reproductive system
• The abdominopelvic cavity

Part 1: Introduction

• Reproduction is the overall function of the reproductive systems
• 4-6 main sub-functions are needed to support reproduction

Biological Sex vs Gender

• Biological sex in humans is typically defined as binary, but is approximately binary and not 100% binary
• Some individuals are intersex
• Definitions vary of intersex
• Presence/absence of functional SRY gene and testes usually matches testosterone levels and responses to testosterone but not always
• Gender is defined and has options

Development of Reproductive Organs

• At about 6 weeks in development, the embryo’s gonads develop as testes or as ovaries
• Testosterone levels vary
• Uterus/vas deferens, clitoris/penis develop as male or female (e.g., penis vs. clitoris)

Secondary Sex Characteristics

• The secondary characteristics that emerge during puberty as driven by hormones are important in defining sex

Meiosis vs Mitosis

• Meiosis is necessary in sexual reproduction because of chromosomes
• The processes differ in terms of:
• Number of cells at end
• Number of chromosomes at end
• Number of divisions
• Formation of tetrads (pairs of replicated homologous chromosomes)

Male Reproductive System

• The male gametes should be memorized
• The male gonads and their location are important topics
• Includes what their two main products are
• The structures through which the gametes pass are important

Meiosis in Males: Spermatogenesis

• Sperm production takes place in a specific location
• Location includes tubules
• Location includes an organ
• Numbers 46 and 23 are important

Structure & Function of a Mature Sperm

• Three parts
• Head
• Should know the function
• Midpiece
• Should know the function
• Tail
• Should know the function

Male Accessory Glands

• The overall function is a key aspect
• Specific glands that should be labeled:
• Urinary bladder (NOT a gland)
• Prostate gland
• Seminal vesicles (seminal glands)
• Bulbourethral (Cowper's) glands
• Ejaculatory duct

Accessory Glands: Semen Composition

• Semen components consists of fructose, coagulation factors, and prostaglandins in seminal vesicle fluid and buffers are in prostatic fluid, bulbourethral fluid
• Approximately 65% from seminal vesicles
• Approximately 25% Prostatic fluid
• Approximately 1% is from the bulbourethral gland
• Approximately 10% Epididymis Fluid

The Urethra and Penis

• Should name/label the different sections of the urethra
• At some point the chemical composition of semen is finalized
• Three corpora can be labelled
• A reproductive function is enabled by the corpora becoming engorged with blood

Determining Sperm Location

• Identify components of the male reproductive tract using distinctive landmarks such as the vas deferens or urethra
• Apply knowledge of where sperm go and where accessory glands add seminal fluids

Part 3: Female Reproductive System

• What the female gametes are
• Identify/be able to locate the female gonads
• Includes their main products
• Where fertilization occurs
• What the three layers of the uterus are

The Ovaries and the Ovarian Cycle

• The ovarian cycle should be labeled/identified
• There is a feature that indicates when ovulation is near
• The released oocyte goes to a specific place
• A specific event occurs to a follicle after ovulation

Meiosis In Females: Oogenesis

• Each primary oocyte gives rise to a specific number of eggs
• Each unfertilized egg contains a number of chromosomes
• A specific chromosomal count results if a sperm fertilizes an egg

Uterus

• Ligaments hold the uterus in place
• Should identify the ligament connecting the ovary with the uterus
• And thus could be mistaken for a fallopian tube
• Should know the layers of the uterus

Ovarian and Uterine Cycles

• All menstruating females do not ovulate on day 14 of a 28-day cycle

Histological Changes

• Changes in the endometrium and the ovaries during phases (menstrual and proliferative) are important to know

Predicting Reproductive Anatomy

• Consider development at two branchpoints
• Presence or absence of a functional SRY gene generally determines gonads (ovaries or testes)
• Levels of testosterone secretion and response generally determine other sexual traits (e.g. other genitalia)

Cell Production

• Identify a process as meiosis or mitosis based on whether it cuts the number of chromosomes per cell in half (meiosis) or maintains the current number of chromosomes (mitosis)

Linking Anatomy to Cycle Phase

• Understand the correlations between phases of the ovarian cycle and uterine cycle well enough to jump back and forth between the two.

Part 4: The Abdominopelvic Cavity And Quadrants

• The abdominopelvic quadrants are important
• The four quadrants covered are:
• Right upper quadrant
• Left upper quadrant
• Right lower quadrant
• Left lower quadrant
• The rectum, urinary bladder, uterus, and vagina are not listed above, therefore they are important

Abdominopelvic Cavity: The 9 Regions

• Name the 9 abdominopelvic regions
• Give the region of each of the following non-visible reproductive or urinary organs:
• Kidneys
• Ureters
• Ovaries/prostate
• Includes the:
• Gland
• Rectum
• Testes
• Uterus
• Vagina

The Transverse Section

• Identify structures

Directional Terms for Organs

• Review the directional terms from Chapter 1
• Lateral/medial
• Dorsal/ventral
• To make sure to apply them to reproductive and other organs

Torso Image

• Consider relative position related to the torso and transverse images
• Lateral/medial
• Number (paired/unpaired)
• Size as needed