1. KEY CONCEPT Germs cause many diseases in humans.

2. Germ theory states that microscopic particles cause certain diseases.
Germ theory proposes that microorganisms cause diseases.
proposed by Louis Pasteur
led to rapid advances in understanding disease

3. Koch’s postulates support the theory. (DON”T COPY)
Disease-causing agents are called pathogens. (COPY)

4. There are different types of pathogens.
Bacteria are single-celled organisms.
cause illness by destroying cells
release toxic chemicals

5. Viruses are genetic material surrounded by a protein coat.
force host cells to make more viruses
very small

6. Fungi can be multicellular or single-celled.
take nutrients from host cells
occur in warm and damp places

7. Protozoa are single-celled organisms.
use host cells to complete their life cycles
take nutrients from host cell

8. Parasites are multicellular organisms.
grow and feed on a host
possibly kill the host

9. READ BUT DON’T COPY
Different pathogen cause common infectious diseases.

10. Pathogens can enter the body in different ways. (READ BUT DON’T COPY)
Pathogens can be transferred by direct or indirect contact.
Indirect contact does not require touching an infected individual.
touching an infected surface
breathing in infected air

11. Vectors carry a pathogen and transmit it into healthy cells.
READ BUT DON’T COPY
Vectors carry a pathogen and transmit it into healthy cells.
Direct contact requires touching an infected individual. Includes:
kissing
sexual intercourse
hand shaking
tick

12. 31.2: Immune System
KEY CONCEPT The immune systems consists of organs, cells, and molecules that fight infections.

13. Many body systems protect you from pathogens.
31.2: Immune System
Many body systems protect you from pathogens.
The immune system is the body system that fights off infection and pathogens.
Many other tissues and systems help the immune system.
Skin is a physical barrier to infection.
Mucous membranes trap pathogens entering the body.
The circulatory system transports immune cells.

14. Cells and proteins fight the body’s infections.
31.2: Immune System
Cells and proteins fight the body’s infections.
White blood cells attack infections inside the body.
Phagocytes engulf and destroy pathogens.
T cells destroy infected cells.
B cells produce antibodies.
READ BUT DON’T COPY

15. 31.2: Immune System
READ BUT DON’T COPY Immunity prevents a person from getting sick from a pathogen.
In all immunity, pathogens are destroyed before you get sick.
Passive immunity occurs without an immune response.
mother’s milk
genetics
Active immunity occurs after a specific immune response

16. 31.3: Immune Responses
KEY CONCEPT The immune system has many responses to pathogens and foreign cells.

17. 31.3: Immune Responses
In fever, body temperature increases.
Low fevers stimulate white blood cells to mature.
High fevers can cause seizure, brain damage, and even death.

18. The immune system rejects foreign tissues.
31.3: Immune Responses (READ BUT DON’T COPY)
The immune system rejects foreign tissues.
Tissue rejection occurs in organ or tissue transplants.
Tissue rejection is the result of an immune response.
immune system detects protein markers on the donor tissue
makes antibodies against the donor’s tissue
(READ BUT DON’T COPY)

19. 34.1: Reproductive Anatomy
KEY CONCEPT Female and male reproductive organs fully develop during puberty.

20. The female reproductive system produces ova.
34.1: Reproductive Anatomy
The female reproductive system produces ova.
There are two main functions of the female reproductive system.
produce ova, or egg cells
provide a place where a zygote develops
uterus
cervix
rectum
vagina
urethra
urinary bladder
pubic bone
ovary
fallopian
tube

21. 34.1: Reproductive Anatomy
Estrogen has three main functions.
develop female sexual characteristics
develop eggs
prepare uterus for pregnancy

22. The male reproductive system produces sperm.
34.1: Reproductive Anatomy
The male reproductive system produces sperm.
There are two main functions of the male reproductive system.
produce sperm cells
deliver sperm to the female reproductive system
urinary bladder
vas deferens
pubic bone
prostate gland
penis
urethra
testis
scrotum
epididymis
bulbourethral
gland
rectum
seminal vesicle

23. 34.1: Reproductive Anatomy
Testosterone has two main functions.
developing male sexual characteristics
producing sperm

24. 34.2: Reproductive Processes
KEY CONCEPT Human reproductive processes depend on cycles of hormones.

25. Eggs mature and are released according to hormonal cycles.
34.2: Reproductive Processes
Eggs mature and are released according to hormonal cycles.
potential
egg
first polar
body
second polar
ovum (egg)
Meiosis I
Completed
Meiosis II
only after
sperm
enters
meiosis produces eggs and polar bodies
each egg has 23 chromosomes
meiosis is completed at fertilization

26. 34.2: Reproductive Processes
Hormones, including estrogen stimulate the release of eggs.
Begins with ovulation (release of an egg from ovary)
egg travels into fallopian tube, then to uterus
fallopian
tube
egg cell
egg released
corpus luteum
uterine wall
ovary
follicle
uterus
5 to 7 days to uterus

27. Eggs mature and are released according to hormonal cycles.
34.2: Reproductive Processes READ BUT DON’T COPY
Eggs mature and are released according to hormonal cycles.
The menstrual cycle has three phases.
1. endometrium sheds
2. ovulation occurs
3. corpus luteum forms

28. 34.2: Reproductive Processes
The menstrual cycle stops at menopause.
cycle continues until a woman’s mid-40’s or 50’s
decline in hormone levels make cycles irregular
eventually, cycle stops altogether

29. Sperm production in the testes is controlled by hormones.
34.2: Reproductive Processes
Sperm production in the testes is controlled by hormones.
Hormones stimulate sperm production.
one sex cell divides into four sperm
each sperm has 23 chromosomes
potential
sperm
4 sperm cells
Meiosis I
Meiosis II

30. Fertilization occurs when a sperm cell joins an egg cell.
34.2: Reproductive Processes
Fertilization occurs when a sperm cell joins an egg cell.
Sperm penetrates an egg.
membrane keeps out other sperm
nucleus of sperm joins with egg
zygote formed

31. 34.2: Reproductive Processes (READ BUT DON’T COPY)
Multiple zygotes can result from fertilization.
identical twins from the same egg
fraternal twins from two separate eggs
Infertility makes reproduction difficult or impossible.

32. Sexually transmitted diseases affect fertility and overall health.
34.2: Reproductive Processes (READ BUT DON’T COPY)
Sexually transmitted diseases affect fertility and overall health.
Sexually transmitted diseases (STDs) are passed from one person to another during sexual contact.
bacterial STDs include chlamydia, syphilis, gonorrhea
viral STDs include hepatitis B, genital herpes, human papillomavirus, and HIV
HIV

33. 34.2: Reproductive Processes (READ BUT DON’T COPY)
Bacterial STDs can be treated, and in many cases, cured with antibiotics
Viral STDs can be treated, but there is no cure for these diseases.
STDs attack reproductive organs.
can cause infertility
untreated, some can be fatal
A parasite causes trichomoniasis, which can affect fertility.
STDs can be avoided by abstinence or by using a condom.

34. 32.3
KEY CONCEPT Development progresses in stages from zygote to fetus.

35. The zygote becomes a blastocyst and implants in the uterus.
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.
READ BUT DON’T COPY
ectoderm develops into skin and nervous system
mesoderm develops into Internal tissues and organs
endoderm develops into digestive organs and their lining
blastocyst
uterine wall
Implantation of blastocyst

36. The blastocyst becomes an embryo.
Embryonic membranes protect and nourish the embryo.
amniotic sac cushions embryo.
placenta connects mother and embryo.
umbilical cord connects embryo to placenta.
placenta
umbilical cord
uterus
amniotic sac

37. 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
Leave a few lines for notes here

38. 2nd trimester: fetus more active, developed
Leave a few lines for notes here

39. 3rd trimester: all organs fully formed
Leave a few lines for notes here
After about 38 weeks, fetus is ready to be born.

40. READ BUT DON’T COPY The mother affects the fetus, and pregnancy affects the mother.
The fetus depends on the mother for all its nutrition.
mother's diet must support fetal health
mother must avoid toxic chemicals

41. READ BUT DON’T COPY
The mother’s health is affected by pregnancy in a number of ways.
increase in Calories and body weight
pregnancy hormones affecting homeostasis
regular medical checkups needed