Iowa State Bio 212 Exam 3

autocrine signals

act on the same cell that secretes them

paracrine signals

diffuse to and affect nearby cells

endocrine signals

hormones carried between distant cells by blood or other bodily fluids

neural signals

diffuse a short distance between neurons

neuroendocrine signals (neurohormones)

hormones released from neurons

negative feedback

response in which the product of a process inhibits its production

positive feedback

response in which the product of a process stimulates its production

endocrine glands

organs that secrete hormones into the bloodstream

exocrine glands

organs that secretes some substance through a duct into a space other than the circulatory system

hormone receptors

protein to which a hormone binds to either inside the cell or attached to the cell

growth hormone

peptide hormone that promotes lengthening of the long bones in children and muscle growth, tissue repair, and lactation in adult

epinephrine

hormone produced and secreted by the adrenal medulla that triggers the flight-or-fight response

cortisol

hormone produced and secreted by the adrenal cortex that mediates the body's long-term stress response

hormone-response element

specific sequence in DNA to which a hormone-receptor complex can bind and affect gene transcription

signal transduction

process by which a stimulus (ex. hormone or neurotransmitter) outside a cell is converted to an intracellular required for a cellular response

second messenger

nonprotein signaling molecule that increases in concentration within a cell in response to a signaling molecule that binds to the surface of the cell

phosphorylase

enzyme that breaks down glycogen by catalyzing hydrolysis of the alpha-glycosidic linkages between glucose molecules

Cyclic AMP

a small molecule, derived from ATP, that is widely used by cells in signal transduction and transcriptional control

Signal transduction cascade

enzyme-catalyzed phosphorylation reactions commonly used in signal transduction pathways to amplify and convey a signal inward from the plasma membrane

Fight-or-flight response

rapid physiological changes that prepare the body for emergencies. Includesincreased heart rate, increased blood pressure, and decreased digestion

Glucocorticoid

any steroid hormone, produced and secreted by the adrenal cortex, that increases blood glucose concentration and mediate the body's long-term stress response

Homeostasis

the maintenance of relatively constant physical and chemical conditions inside the body

Hormones

information-carrying molecules that are secreted by plant and animal cells into bodily fluids and act on distant target cells

Signal Receptor

a protein that changes its shape and activity after binding to a signaling molecule

G proteins

various proteins that lead to production of second messenger or initiation of a phosphorylation cascade

Second messenger

small, nonprotein signaling molecule or ion that elicits an intracellular response to the first messenger

GTP

functions in signal transduction in association with G proteins and acts as a regulator for G proteins

Protein kinases

enzymes that activate or inactivate other proteins by adding phosphate groups to them

RTKs

any class of enzyme-linked cell-surface receptors that phosphorylate themselves after binding a signaling molecule

Phosphorylation cascade

enzyme-catalyzed phosphorylation reaction commonly used in signal transduction pathways to amplify and convey a signal inward from a plasma membrane

Phosphatases

enzymes that remove phosphate groups from components of the phosphorylation cascade, causing the signal transduction to cease

Crosstalk

interactions amongdifferent signaling pathways that modify the cell response

Development

Process of a single-celled individual becoming multicellular

zygote

fertilized egg

embryo

developing organism from about 2 weeks after fertilization

stem cells

unspecialized cells, usually create two daughter cells and one differentiates

Differentiation

process in which cells become specialized in structure and function (via induction or cytoplasmic determinants)

Induction

A cell is signaled and changes based on the signal

Cytoplasmic determinants

a molecule that resides in one of the two daughter stem cells, that causes a change in gene activity

Gastrulation

a rearrangement of cells, that sort into the three layers of the embryo, theEctoderm, Endoderm, and Mesoderm

Programmed Cell Death

the highly regulated process of cells that are no longer needed dying

Apoptosis

a form of programmed cell death in animals

Genetic Equivalence

differentiated cells contain the genetics for a different differentiation of cells

Regulatory Transcription Factors

proteins that bind to DNA regulatory sequences like enhancers and silencers, but not to promoters and help regulate transcription

anterior

toward head

posterior

toward tail

dorsal

backside

ventral

belly side

pattern formation

is the process of spatial organization meaning that some cells will be targeted to the head and the others will become tail cells

morphogen

a molecule that provides spatial information to embryo cells

Genetic regulatory cascade

regulatory genes that trigger a chain of regulatory genes causing a cascade of gene regulation

Homeotic mutations

a mutation that substitutes one body part for another

Homologous

similar due to shared ancestors

Commitment

occurs when a cell becomes dedicated to a particular specialization

Master Regulator

gene or protein that produce specialized cell types, tissues, or structures

IPS cells

an undifferentiated cell that was made by experimental de differentiation of an adult cell, has the potential to become any cell in the body if handled properly

Asexual reproduction

No gamete fusion, and results in genetically similar offspring via budding, fission, or parthenogenesis

Sexual reproduction

the fusion of two gametes and results in genetically different offspring

Budding

Offspring forms within the parent and then "buds off" and grows on its own

Fission

The parent splits in half to create offspring

Parthenogenesis

female produced offspring, which can be done by mitosis or meiosis

sperm

male gametes

eggs

female gametes

Fertilization

the process by which the sperm and egg fuse together

Proximate causation

used to address how a trait is produced and is found by looking at genes, development, and hormones

Ultimate causation- used to address why a trait occurs in terms of fitness

Ultimate causation- used to address why a trait occurs in terms of fitness

Gametogenesis

production of gametes (spermatogenesis in males, oogenesis in females)

Gonads

sex organs (testes in males, ovaries in females)

Acrosome

head of the sperm, stores enzymes that allow for penetration of the egg

Flagellum

long tail structure that sperm use for swimming

Polar bodies

cells with low amounts of cytoplasm that disintegrate after the formation

yolk

fat and rich cytoplasm found in eggs

Vitelline envelope

a fibrous sheet of glycoproteins that surrounds the egg

Viviparous

Live bearing, meaning embryo development takes place inside of the mother

Oviparous

Egg bearing, embryo development takes place outside of the mother

Sperm competition

competition between sperm from different males to fertilize eggs of one female

Second male advantage

an advantage that is given to the second male, as the second male's sperm can displace the first male's sperm

Cleavage

rapid cellular division

Blastomeres

cells created during cleavage

Blastula

a mass of blastomeres

Blastocytes

Blastula that contains two kinds of cells in it

Trophoblast

found in the blastula exterior

Inner cell mass

cells on the inside of the blastula

Placenta

the trophoblast develops into the placenta, and the placenta exchanges nutrients and waste between the embryo and the mother

Ectoderm

Outer layer of gastrulated layers

Mesoderm

Middle layer of gastrulated layers

Endoderm

inner layer of the gastrulated layers

Notochord

Supportive, flexible rod in embryos that become the spine

Neural tube

folded tube in ectoderm that becomes the brain and spinal cord

Somites

Blocks in the mesoderm that develop into muscles, ribs, and skin

Follicle

sac of supportive cells that also contain an egg

Puberty

the transition from juvenile to adult

Menstrual cycle

the expulsion of the uterine line

Follicular phase

the phase where the follicle matures and last about 14 days

Luteal phase

begins with ovulation and last about 14 days, and has the corpus luteum life cycle take place

Corpus luteum

]a structure made after the rupture of the follicle that degenerates if not fertilized

Fetus

embryo past the first 8 weeks of pregnancy

Amnion-

The innermost membrane surrounding the embryo in the amniotic egg