Unit 10 The Human Body Ch. 39 Endocrine & Reproductive Systems.

Unit 10 The Human BodyUnit 10 The Human Body

Ch. 39 Endocrine & Reproductive Systems

Ch. 39 Endocrine & Reproductive Systems

The Endocrine SystemThe Endocrine System

The endocrine system is made up of glands that release their products into the bloodstream

These products deliver messages throughout the body

The endocrine system is made up of glands that release their products into the bloodstream

These products deliver messages throughout the body

HormonesHormones

Hormones - chemicals released in 1 part of the body, that travel through the bloodstream, & affect activities of cells in other parts of the body; “chemical messengers”

Target cells (receptor cells) - cells that have receptors for a particular hormone

Hormones - chemicals released in 1 part of the body, that travel through the bloodstream, & affect activities of cells in other parts of the body; “chemical messengers”

Target cells (receptor cells) - cells that have receptors for a particular hormone

GlandsGlands

A gland is an organ that produces & releases a substance, or secretion

Exocrine glands - release their secretions (hormones) through ducts (tubes), directly to the organs that use them

A gland is an organ that produces & releases a substance, or secretion

Exocrine glands - release their secretions (hormones) through ducts (tubes), directly to the organs that use them

GlandsGlands

Endocrine glands - release their secretions (hormones) directly into the bloodstream

Endocrine glands - release their secretions (hormones) directly into the bloodstream

Major Endocrine GlandsMajor Endocrine Glands

Hormone ActionHormone Action

Steroid hormones: Because they are lipids, they

can cross cell membranes, passing directly into the cytoplasm & the nuclei of target cells

Steroid hormones: Because they are lipids, they

can cross cell membranes, passing directly into the cytoplasm & the nuclei of target cells

Hormone ActionHormone Action

Nonsteroid hormones: They generally cannot pass

through the cell membrane of their target cells

Nonsteroid hormones: They generally cannot pass

through the cell membrane of their target cells

ProstaglandinsProstaglandins

Prostaglandins - modified fatty acids that produce cells, affecting other nearby cells & tissues (“local hormones”) Ex.) some cause smooth muscle tissue to

contract

Prostaglandins - modified fatty acids that produce cells, affecting other nearby cells & tissues (“local hormones”) Ex.) some cause smooth muscle tissue to

contract

Control of the Endocrine System

Control of the Endocrine System

Like most systems of the body, the endocrine system is regulated by feedback mechanisms that function to maintain homeostasis Ex.) Pancreas releasing insulin: blood sugar

level increases after lunch, pancreas releases insulin, blood sugar level decreases, pancreas stops releasing insulin

Like most systems of the body, the endocrine system is regulated by feedback mechanisms that function to maintain homeostasis Ex.) Pancreas releasing insulin: blood sugar

level increases after lunch, pancreas releases insulin, blood sugar level decreases, pancreas stops releasing insulin

Human Endocrine GlandsHuman Endocrine Glands

The human endocrine system regulates a wide variety of activities

Any improper functioning of an endocrine gland may result in a disease or disorder

The human endocrine system regulates a wide variety of activities

Any improper functioning of an endocrine gland may result in a disease or disorder

Human Endocrine GlandsHuman Endocrine Glands

The major glands of the endocrine system are: the pituitary gland, the hypothalamus, the thyroid gland, the parathyroid glands, the adrenal glands, the pancreas, & the reproductive glands

The major glands of the endocrine system are: the pituitary gland, the hypothalamus, the thyroid gland, the parathyroid glands, the adrenal glands, the pancreas, & the reproductive glands

Pituitary GlandPituitary Gland

Pituitary gland - divided into 2 parts: anterior & posterior; it secretes 9 hormones that directly regulate many body functions & controls the actions of several other endocrine glands

Pituitary gland - divided into 2 parts: anterior & posterior; it secretes 9 hormones that directly regulate many body functions & controls the actions of several other endocrine glands

Pituitary Gland HormonesPituitary Gland Hormones

HypothalamusHypothalamus

The hypothalamus controls the secretions of the pituitary gland

The close connection between the hypothalamus & the pituitary gland, means that the nervous & endocrine systems can act together to help coordinate body activities

The hypothalamus controls the secretions of the pituitary gland

The close connection between the hypothalamus & the pituitary gland, means that the nervous & endocrine systems can act together to help coordinate body activities

Thyroid GlandThyroid Gland

The thyroid gland has the major role in regulating the body’s metabolism

Releases thyroxin which increases metabolism, & cellular respiration

The thyroid gland has the major role in regulating the body’s metabolism

Releases thyroxin which increases metabolism, & cellular respiration

Thyroid GlandThyroid Gland

Unable to produce thyroxin produces condition known as cretinism

2 effects of cretinism are dwarfism & severe mental retardation

Can be prevented by adding small amounts of iodine to table salt

Unable to produce thyroxin produces condition known as cretinism

2 effects of cretinism are dwarfism & severe mental retardation

Can be prevented by adding small amounts of iodine to table salt

Parathyroid GlandsParathyroid Glands

The 4 parathyroid glands are found on the back surface of the thyroid gland

Hormones from the thyroid gland & the parathyroid glands act to maintain homeostasis of calcium levels in the blood

The 4 parathyroid glands are found on the back surface of the thyroid gland

Hormones from the thyroid gland & the parathyroid glands act to maintain homeostasis of calcium levels in the blood

Adrenal GlandsAdrenal Glands

There are 2 adrenal glands that sit on top of the kidneys, like little hats

The adrenal glands release hormones that help the body prepare for & deal with stress

There are 2 adrenal glands that sit on top of the kidneys, like little hats

The adrenal glands release hormones that help the body prepare for & deal with stress

Adrenal GlandsAdrenal Glands

The 2 hormones secreted by the adrenal glands are: epinephrine and norepinephrine

The hormones produce the “fight or flight” response to stress

The 2 hormones secreted by the adrenal glands are: epinephrine and norepinephrine

The hormones produce the “fight or flight” response to stress

PancreasPancreas

The pancreas has both exocrine & endocrine functions

It is a digestive gland whose enzymes help break down food

However, different cells in the pancreas release hormones into the blood

The pancreas has both exocrine & endocrine functions

It is a digestive gland whose enzymes help break down food

However, different cells in the pancreas release hormones into the blood

PancreasPancreas

Insulin & glucagon are released from the pancreas to help keep the blood glucose level stable

Insulin stimulates liver cells to remove sugar from the blood & store it as glycogen

Glucagon stimulates the liver to break down stored glycogen & release sugar back into the blood

Insulin & glucagon are released from the pancreas to help keep the blood glucose level stable

Insulin stimulates liver cells to remove sugar from the blood & store it as glycogen

Glucagon stimulates the liver to break down stored glycogen & release sugar back into the blood

PancreasPancreas

Diabetes mellitus - when the pancreas does not produce insulin

There are 2 types of diabetes, Type I and Type II

Type I requires daily injections of insulin, due to the fact that the body produces no insulin

Diabetes mellitus - when the pancreas does not produce insulin

There are 2 types of diabetes, Type I and Type II

Type I requires daily injections of insulin, due to the fact that the body produces no insulin

PancreasPancreas

Type II develops in people after the age of 40, produces normal insulin but cells don’t respond properly to the hormone

Usually controlled through diet, exercise, & medication taken orally

Type II develops in people after the age of 40, produces normal insulin but cells don’t respond properly to the hormone

Usually controlled through diet, exercise, & medication taken orally

Reproductive GlandsReproductive Glands

The gonads are the body’s reproductive glands

They serve 2 important functions: the production of gametes & the secretion of sex hormones

The gonads are the body’s reproductive glands

They serve 2 important functions: the production of gametes & the secretion of sex hormones

Reproductive GlandsReproductive Glands

The female gonads are the ovaries - which produce eggs, & the hormones estrogen & progesterone

The male gonads are the testes - which produce sperm, & the hormone testosterone

The female gonads are the ovaries - which produce eggs, & the hormones estrogen & progesterone

The male gonads are the testes - which produce sperm, & the hormone testosterone

The Reproductive SystemThe Reproductive System

Reproduction is the formation of new individuals

If any other system of the body failed, the result would be fatal, not the case with the reproductive system

Reproduction is important for continuation of the species, but not for that organism to survive

Reproduction is the formation of new individuals

If any other system of the body failed, the result would be fatal, not the case with the reproductive system

Reproduction is important for continuation of the species, but not for that organism to survive

Sexual DevelopmentSexual Development

For the 1st 6 weeks of development, male & female embryos are identical

During the 7th week, primary reproductive organs begin to develop

Hormones produced by those organs (gonads), will determine whether the embryo develops physically into a male or female

For the 1st 6 weeks of development, male & female embryos are identical

During the 7th week, primary reproductive organs begin to develop

Hormones produced by those organs (gonads), will determine whether the embryo develops physically into a male or female

Sexual DevelopmentSexual Development

Neither the testes nor the ovaries are capable of producing active reproductive cells until puberty

Puberty - a period of rapid growth & sexual maturation, when the reproductive system becomes fully functional

Neither the testes nor the ovaries are capable of producing active reproductive cells until puberty

Puberty - a period of rapid growth & sexual maturation, when the reproductive system becomes fully functional

The Male Reproductive SystemThe Male Reproductive System

The main function of the male reproductive system is to produce & deliver sperm

Scrotum - external sac that holds the gonads, (external to reduce heat so sperm won’t die)

Seminiferous tubules - tiny tubules tightly coiled where the sperm are produced

The main function of the male reproductive system is to produce & deliver sperm

Scrotum - external sac that holds the gonads, (external to reduce heat so sperm won’t die)

Seminiferous tubules - tiny tubules tightly coiled where the sperm are produced


Sperm - male sex cells (gametes) Sperm - male sex cells (gametes)


Epididymis - structure that sperm move into, to mature & be stored until released

Vas deferens - tube that carries sperm from the epididymis, to the urethra, to be released

Penis - urethra carries sperm out of body through the penis

Epididymis - structure that sperm move into, to mature & be stored until released

Vas deferens - tube that carries sperm from the epididymis, to the urethra, to be released

Penis - urethra carries sperm out of body through the penis

The Female Reproductive System


The main function of the female reproductive system is to produce ova (eggs)

In addition, the female reproductive system prepares the female’s body to nourish a developing embryo

The main function of the female reproductive system is to produce ova (eggs)

In addition, the female reproductive system prepares the female’s body to nourish a developing embryo



Follicles - each ovary contains 400,000 clusters of cells surrounding a single egg, to help it mature

Ovulation - when a follicle has completely matured, its egg is released

Follicles - each ovary contains 400,000 clusters of cells surrounding a single egg, to help it mature

Ovulation - when a follicle has completely matured, its egg is released



Egg - female sex cells (gametes) Fallopian tubes - tube from each ovary,

that carries the egg to the uterus

Egg - female sex cells (gametes) Fallopian tubes - tube from each ovary,

that carries the egg to the uterus



Uterus - location of egg a couple days after ovulation, where embryo develops if fertilization takes place

Cervix - the outer end of the uterus Vagina - a canal that leads to the outside

of the body

Uterus - location of egg a couple days after ovulation, where embryo develops if fertilization takes place

Cervix - the outer end of the uterus Vagina - a canal that leads to the outside

of the body

The Menstrual CycleThe Menstrual Cycle

Menstrual cycle - when an egg develops & is released from an ovary

The menstrual cycle has 4 phases: follicular phase, ovulation, luteal phase, & menstruation

Menstrual cycle - when an egg develops & is released from an ovary

The menstrual cycle has 4 phases: follicular phase, ovulation, luteal phase, & menstruation


The Follicular Phase Development of an egg

Ovulation Lasts 3-4 days, a mature egg

is released into 1 of the fallopian tubes

The Follicular Phase Development of an egg

Ovulation Lasts 3-4 days, a mature egg

is released into 1 of the fallopian tubes


Luteal Phase The remaining ruptured follicle, which

continues to release hormones Menstruation - when the lining of the

uterus sheds, lasts about 3-7 days (period)

Luteal Phase The remaining ruptured follicle, which

continues to release hormones Menstruation - when the lining of the

uterus sheds, lasts about 3-7 days (period)

Sexually Transmitted DiseasesSexually Transmitted Diseases

Sexually transmitted diseases - diseases spread from 1 person to another through sexual contact

Common STDs are chlamydia, syphilis, & gonorrhea (caused by a bacteria)

Sexually transmitted diseases - diseases spread from 1 person to another through sexual contact

Common STDs are chlamydia, syphilis, & gonorrhea (caused by a bacteria)

Sexually Transmitted DiseasesSexually Transmitted Diseases

Others caused by viruses include: HIV, hepatitis B, genital herpes, & genital warts

Others caused by viruses include: HIV, hepatitis B, genital herpes, & genital warts

FertilizationFertilization

When an egg is fertilized, the process of human development begins

In this process, a single cell, the size of a period at the end of a sentence, undergoes cell divisions that results in the formation of a new human being

When an egg is fertilized, the process of human development begins

In this process, a single cell, the size of a period at the end of a sentence, undergoes cell divisions that results in the formation of a new human being

FertilizationFertilization

Fertilization - the process of a sperm joining an egg, usually occurs in the fallopian tube

Zygote - a fertilized egg

Fertilization - the process of a sperm joining an egg, usually occurs in the fallopian tube

Zygote - a fertilized egg

Early DevelopmentEarly Development

The stages of early development include: implantation, gastrulation, & neurulation

Implantation - when the blastocyst implants itself in the uterine wall

At this point, cells differentiate - develop into specific types of tissues in the body

The stages of early development include: implantation, gastrulation, & neurulation

Implantation - when the blastocyst implants itself in the uterine wall

At this point, cells differentiate - develop into specific types of tissues in the body


Gastrulation - the formation of 3 cell layers; the beginning of all of the organs & tissues of the embryo will form from these 3 layers

Gastrulation - the formation of 3 cell layers; the beginning of all of the organs & tissues of the embryo will form from these 3 layers


Neurulation - the development of the nervous system, occurs shortly after gastrulation

Neurulation - the development of the nervous system, occurs shortly after gastrulation


Placenta - connections between mother & developing embryo

The embryo needs a supply of nutrients & oxygen, & a way to get rid of carbon dioxide & wastes

Nutrients & oxygen diffuse from the mother’s blood into the baby’s blood

Placenta - connections between mother & developing embryo

The embryo needs a supply of nutrients & oxygen, & a way to get rid of carbon dioxide & wastes

Nutrients & oxygen diffuse from the mother’s blood into the baby’s blood


At the same time, carbon dioxide & metabolic wastes diffuse from the baby’s blood into the mother’s blood, to be excreted

The placenta is the embryo’s organ of respiration, nourishment, & excretion

At the same time, carbon dioxide & metabolic wastes diffuse from the baby’s blood into the mother’s blood, to be excreted

The placenta is the embryo’s organ of respiration, nourishment, & excretion

The PlacentaThe Placenta


Fetus - after 8 weeks of development, the embryo is then called a fetus

The umbilical cord connects the fetus to the placenta

Pregnancy, is divided into 3 trimesters, during the 3rd, the organ systems mature, & the fetus grows in size & mass

Fetus - after 8 weeks of development, the embryo is then called a fetus

The umbilical cord connects the fetus to the placenta

Pregnancy, is divided into 3 trimesters, during the 3rd, the organ systems mature, & the fetus grows in size & mass

Later DevelopmentLater Development

ChildbirthChildbirth

After 9 months, the fetus is ready for birth Oxytocin, a hormone released from the

pituitary gland, causes contractions to begin

The contractions become more frequent & powerful

After 9 months, the fetus is ready for birth Oxytocin, a hormone released from the

pituitary gland, causes contractions to begin

The contractions become more frequent & powerful

ChildbirthChildbirth

The cervix opening expands until it is large enough for the baby’s head to pass through

Contractions of the uterus force the baby out through the vagina

The cervix opening expands until it is large enough for the baby’s head to pass through

Contractions of the uterus force the baby out through the vagina

Unit 10 The Human Body Ch. 39 Endocrine & Reproductive Systems.

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Transcript of Unit 10 The Human Body Ch. 39 Endocrine & Reproductive Systems.