Unit 4 Bio

Sperm

male sex cell, forms in a testis

Eggs

Female sex cell, form in ovaries

internal fertilization

Process in which eggs are fertilized inside the female's body

external fertilization

The process by which the female lays eggs and the male fertilizes them once they are outside of the female

asexual reproduction

Process by which a single parent reproduces by itself

sexual reproduction

A reproductive process that involves two parents that combine their genetic material to produce a new organism, which differs from both parents

sexual reproduction advantages

genetic variation

asexual reproduction advantages

fast, easy, efficient, genetically identical

Hermaphroditism

A condition where both ovarian and testicular tissue are found in the same individual, they can give sperm and eggs

Fission

mitosis/ individual splits to create 2

Budding

A form of asexual reproduction of yeast in which a new cell grows out of the body of a parent.

Fragmentation

The breaking of body into two parts with subsequent regeneration

parthenogenesis

Asexual reproduction in which females produce offspring from unfertilized eggs.

How is mammalian sex determined biologically?

presence of y and X chromosomes

How is avian sex determined?

presence of Z and W chromosomes

Environmental sex determination

Sex determined by environmental factors, such as temp

"Male first"

Protandry

"Female first"

Protogyny

spawning

method of reproduction in fishes and some other animals where a large number of eggs are fertilized outside of the body

Oviparty

Eggs are laid outside the body (chickens)

Ovoviviparity

Eggs are retained in the parent

Viviparity

live birth

How are snake eggs different from bird eggs

Snake eggs are leathery and bird eggs are pure calcium

spermatheca

Specialized sac in many insects that stores sperm for later use

Cloaca

BIRDS common opening for digestive, urinary, and reproductive tracts

Why do some organisms have more than one uterus?

Produces more offspring

What purpose does the acrosome on a sperm cell serve?

allows sperm to fertilize the eggs

Testes

male gonads, produce sperm and secrete sex hormones

clitoris

structure with erectile tissue that contains a large number of sensory nerves and is a source of stimulation during intercourse

vagina

muscular tube that allows menstrual flow, a receptacle for the penis, and the birth canal.

ovaries

Glands that produce the egg cells and hormones

Scrotum

a pouch of skin containing the testicles.

Testosterone

the most important of the male sex hormones. Both males and females have it, but the additional testosterone in males stimulates the growth of the male sex organs in the fetus and the development of the male sex characteristics during puberty

penis

Male reproductive organ

seminiferous tubules

Narrow, coiled tubules that produce sperm in the testes.

Estrogen

A sex hormone, secreted in greater amounts by females

vas deferens

carries sperm behind the bladder and forms the ejaculatory duct

prostate gland

A gland in males that contributes to the seminal fluid.

ejaculatory duct

tube through which semen enters the male urethra

bulbourethral glands

A pair of exocrine glands near the male urethra. They secrete fluid into the urethra.

seminal vesicles

two small glands that secrete a fluid rich in sugar that nourishes and helps sperm move

vulva

external genitalia of the female

Cervix

The opening to the uterus, protrudes into top of vagina

oviducts

fallopian tubes, move eggs

Fimbriae

finger or fringe like projections at the end of the fallopian tubes

Uterus

Female organ of reproduction used to house the developing fetus.

What is the difference in the number of fertile cells produced in spermatogenesis versus oogenesis?

spermatogenesis produces sperm cells and oogenesis produces one ovum.

Ovarian cycle

governs the prep of endocrine tissues and release of eggs

menstrual cycle

governs prep and maintenance of uterine lining

menopause

the time of natural cessation of menstruation

birth control

prevent unwanted pregnancies

Contraception

preventing sperm and egg combining

gestation

growth process from conception to birth

parturition

act of giving birth

Zygote

fertilized egg

C-section

a surgical method of birth

Placenta

A structure that allows an embryo to be nourished with the mother's blood supply

barrier methods

Contraceptive methods that physically or chemically obstruct the travel of sperm toward the ovum. These devices do not alter body processes with drugs or devices.

hormonal methods

contraceptive methods that introduce synthetic hormones into a woman's system to prevent ovulation, thicken cervical mucus, or prevent a fertilized egg from implanting

vasectomy

bilateral surgical removal of a part of the vas deferens

spermicides

chemically destroy sperm by creating a highly acidic environment in the uterus

IUD

intrauterine device; contraceptive

Natural Family Planning

A morally acceptable way to time pregnancies based on the observation of a woman's naturally occurring times of fertility and infertility

tubal ligation

blocking the fallopian tubes to prevent fertilization from occurring

withdrawal method

a method of contraception in which the man withdraws his penis from the vagina prior to ejaculation

Infertility

the inability to conceive a child

What prevents more than one sperm from fertilizing an egg?

depolarization

Blastula

A hollow ball of cells that marks the end of the cleavage stage during early embryonic development in animals.

cleavage

rapid and multiple rounds of cell division

inner cell mass

The mass of cells in the blastocyst that ultimately give rise to the embryo and other embryonic structues

Gastrulation

a series of cell and tissue movements in which the blastula-stage embryo folds inward, producing a three-layered embryo, the gastrula.

Organogenesis

organ formation that takes place during the first two months of prenatal development

trophoblast

outer cells of the blastocyst that secrete enzymes that allow implantation

Ectoderm

outermost germ layer; produces sense organs, nerves, and outer layer of skin

Endoderm

the inner germ layer that develops into the lining of the digestive and respiratory systems

Mesoderm

middle germ layer; develops into muscles, and much of the circulatory, reproductive, and excretory systems

homebox genes

Genes that control the development of the body plan of an organism.

Pathogen

A disease causing agent

Autoimmunity

reaction of immune response to one's own tissues

host

An organism on which a parasite lives.

zoonotic disease

disease that can be passed between animals and humans

Allergies

Having a hypersensitivity to a substance that does not normally cause a reaction.

Vector

insects that carry/transmit diseases

What is unusual about the thymus as the person ages?

it shrinks

Describe the function of the spleen.

filters toxins from actual blood, removes dying RBCs

Why are viruses considered to be obligate intracellular parasites?

They reproduce only within a host cell

What is the role of an antigen presenting cell?

Phagocytosis of antigens

Which applies to innate defenses?

guard against any pathogens

Which applies to adaptive defenses?

mount a response against a specific pathogen

How is inflammation helpful in fighting infections?

movement of leukocytes

What do Natural Killer Cells do?

Kill virus-infected body cells

What is the function of perforin?

to make pores in target cell

How is fever beneficial to fighting infection?

can kill some microbes

What do helper T cells do?

Tell B cells to make antibodies

What do cytotoxic T cells do?

Kill abnormal and foreign cells

What do B cells do?

secrete antibodies

What is the function of antibodies?

To protect the body from pathogens (bacteria & viruses) as part of the immune system

Where do T cells and B cells mature?

T cells \= Thymus

B cells \= Bone marrow

naturally acquired active immunity

resulting from infection