Human reproductive systemfetal development

SC.912.L.16.13

Describe the basic anatomy and physiology of the human reproductive system. Describe the process of human development from fertilization to birth and major changes that occur in each trimester of pregnancy.

(L2 – MODERATE COMPLEXITY)

BENCHMARK SC.912.L.16.13Reporting Category Organisms, Populations, and Ecosystems

Standard Standard 16 Heredity and Reproduction

Benchmark SC.912.L.16.13 Describe the basic anatomy and physiology of the human reproductive system. Describe the process of human development from fertilization to birth and major changes that occur in each trimester of pregnancy.

BenchmarkClarifications Students will identify and/or describe the basic anatomy and physiology of the

human reproductive system.

Students will describe the process of human development from the zygotic stage to the end of the third trimester and birth.

Content Limits Items referring to the male human reproductive system are limited to the seminal vesicle, prostate gland, vas deferens, urethra, epididymis, scrotum, penis, and

testes.

Items referring to the female human reproductive system are limited to the ovaries, oviduct (fallopian tube), uterus, cervix, and vagina.Items assessing the function of the placenta, umbilical cord, amniotic sac, and amniotic fluid are limited to how these structures relate to the development of the

fetus.

Items will not assess physiological or hormonal changes of the mother during pregnancy.

Items assessing the production of hormones in the context of the physiology of the human reproductive system are limited to a conceptual understanding of the

production of hormones.

Content limits cont. Items will not assess hormonal control during pregnancy.

Items may refer to the early stages of development (implantation, morula, blastocyst, gastrulation, neurulation) but will not assess the definition of these terms.

Items referring to changes in each trimester are limited to normal human development.

Items will not assess specific knowledge of malformations in the human fetus, miscarriages, maternal preexisting conditions, genetic conditions, or the impact of exposure to environmental conditions.

Items will not assess the utilization of technology to assist in or prevent fertilization or monitor development of the fetus.

Items will not address or assess the menstrual cycle.

Stimulus Attribute Illustrations or diagrams may be used.

Response Attributes None specified

Prior Knowledge Items may require the student to apply scientific knowledgedescribed in the NGSSS from lower grades. This benchmark requires prerequisite knowledge of SC.6.L.14.5.

Student Misconceptions

Common Student Misconceptions:

Research indicates that some students cannot distinguish between sexual reproduction and asexual reproduction in order to understand the origins of variation.

Students may confuse gastrulation and neurulation in the stages of embryonic development

Some students have little understanding of the trimesters of pregnancy

Male Reproductive System

Scrotum contains:• Testes

– The seminiferous tubules produce sperm and testosterone

– Require a low temperature – Sperm live up to 72 hrs. in a female

• Epididymis - folds of tissue (700 ft long)– Lies on top of the testes– Sperm mature here with aid from helper sperm (mask

the 23 chromosome sperm from immune system)

• Vas deferens– Connects the external scrotum to the internal pathway.– Curves around the bladder, stores sperm, empties into the urethra– Sperm travel through this during ejaculation

• Urethra– glands including the prostate gland produce a fluid that combines

with the sperm to produce semen, enters here– semen flows through the urethra along with sperm during

ejaculation (out the penis)

Female Reproductive system

(oviduct)

Female Reproductive System

• Ovaries - pair, internal– Mature and release one egg/month– Matures in the follicles within the ovaries– Born with all the eggs a female will ever have– 2 million at birth; 200-400 thousand at puberty; 400 will

mature and be released– Once the egg has been released by the follicles, the

follicles will release hormones for child development if fertilization takes place

• Oviducts or Fallopian tubes– Feathery like projections– After ovulation (releasing of the egg) occurs, the egg enters one

of the oviducts– This is where fertilization occurs as the egg only lives 6-24 hrs.– The egg can’t move so it relies on cilia that lines the duct to

cause a current along with muscle contraction (cramps at ovulation)

– Fertilized egg zygote embryo

Female Reproduction

• Uterus– Embryo will embed itself in lining of uterus

• This causes a hormone to be released (+ pregnancy test result)

– Embryo will develop into a fetus– Uterus: 5 cm wide but expands to 30 cm– Thick walled muscular organ above the bladder

• Cervix – This opening connects the vagina to the uterus– Opening is usually 1 cm wide, but during birth, expands

to 10 cm• Vagina

– Birth canal, site of sexual intercourse, site of menstruation – acidic for immunity reasons

Fetal Development

The fertilized egg implants into the uterus and is nourished by the placenta and umbilical cord.

• The zygote becomes a blastocyst and implants in the uterus.

** Distinguish between gastrulation and neurulation

placenta

umbilical cord

uterus

amniotic sac

The blastocyst becomes an embryo.

• Embryonic membranes protect and nourish the embryo.

– amniotic sac cushions embryo.

– amniotic fluid in the amniotic sac

– placenta connects mother and embryo.

– umbilical cord connects embryo to placenta.

A zygote develops into a fully formed fetus in about 38 weeks.

• Human pregnancies are divided into trimesters. – 1st trimester: body plan and early development

– Most genetic issues occur here

– 2nd trimester: fetus more active, developed

Second Trimester

– 3rd trimester: all organs fully formed

• After about 38 weeks, fetus is ready to be born.

Third Trimester

• Construct a six-page flip-chart• Label the exposed tabs as

– First trimester– Second trimester– Third trimester– Problems That can occur and when– Affects of drugs (have a list of drugs you want them to

research)** or place the last two topics first as there is less room on the

foldable to write information. • Indicate the important changes that occur in each stage as

we cover it in class• Research problems that can occur if the developing fetus

is exposed to drugs such as alcohol or tobacco.

FETAL DEVELOPMENT FOLDABLEInstruction on how to make a foldable

Insert info as we go through the content

Resources• Escambia County Website• Questions from www.problem-attic.com• Fetal Development Sonograms by weeks (active,3D)• http://baby2see.com/development/ultrasound_sonogram/first_trimester_scans.html

• Interactive Developmental Timeline• http://www.classzone.com/cz/books/bio_12_fl/resources/htmls/animated_biology/unit9/bio_ch

34_1045_ab_devtime.html

• Trimester Manipulative (see snapshot below)

EOC Study Guide{SC.912.L.14.52} Explain the basic functions of the human immune system, including specific and nonspecific immune response, vaccines, and antibiotics.

– 1. Give an example of specific and non specific responses.

– 2. How do vaccines prevent disease?

– 3. How do antibiotics prevent disease?

{SC.912.L.16.13} Describe the basic anatomy and physiology of the human reproductive system.

– 1. Describe the process of human development from fertilization to birth and major changes that occur in each trimester of pregnancy (i.e. fertilization, embryo formation, tube formation, organ system formation, heart beat, movement.

– Define embryo•