Biology Ch. 2

G 0 phase

a stage of the cell cycle where the cell is simply living and carrying out its functions with no plans of dividing

chromatin

less condensed form of chromosomes that are not visible with light microscopy

interphase

During what part of the cell cycle is the genetic material not visible?

cells create organelles for making energy and proteins (mitochondria, ribosomes, and ER)

What happens in the G 1 phase?

checks if the cell has enough organelles and cytoplasm for two daughter cells. Checks for errors in DNA replication

What does the checkpoint between G2 and M do?

-makes sure the condition of the DNA is good enough for S

-also known as the restriction point

What does the checkpoint between G 1 and S do?

p53

protein in charge of putting a cell into arrest if the condition of DNA is not good enough to move on to S phase

-also plays a role in the G 2 / M checkpoint

cyclins and cyclin-dependent kinases (CDKs)

What are the two molecules responsible for the cell cycle?

CDKs depend on cyclins

Do cyclins depend on CDKs or do CDKs depend on cyclins?

TP53, which codes for the p53 protein

The name of the gene that gets mutated in the most common example of cancer

tumors

when cancer cells undergo rapid cell division, they produce this

metastasis

when cancerous cells produce the right factors that allow them to spread to other tissues

prophase

During what phase of mitosis do centriole pairs separate and move toward opposite poles of the cell?

centrosome

Where are centrioles located?

spindle fibers

the things that the centrioles form when they are on opposite poles of the cell

aster

star-like appearance of the centrosome and associated microtubules

-the centrosome in an autosomal cell during mitosis

-the basal body of a flagellum or cilium

What are the two microtubule organizing centers of the cell?

prophase

During what phase of mitosis does the nuclear membrane dissolve?

telophase

During what phase of mitosis does the spindle apparatus disappear?

reductional division

type of division shown in meiosis 1 because it generates haploid daughter cells

equational division

type of division shown in meiosis 2 because ploidy does not change

synapsis

during prophase 1 of meiosis 1, when homologous chromosomes come together and intertwine

tetrad

the group that refers to 2 homologous chromosomes next to each other; a total of 4 sister chromatids

chiasma

point where two homologous chromosomes touch each other

synaptonemal complex

group of proteins that holds the homologous chromosomes together

crossing over

process during prophase 1 when homologous chromosomes exchange genes

prophase 1

What step of meiosis explains Mendel’s second law of independent assortment?

anaphase 1

What step of meiosis explains Mendel’s first law of segregation? (Homologues can line up on either side of the metaphase plate)

interkinesis

a short rest period during telophase 1 where chromosomes partially uncoil

X has a lot, Y has a little

How much genetic info does the X chromosome contain? Y chromosome?

SRY (sex-determining region Y)

gene on the Y chromosome that codes for a transcription factor that initiates testis differentiation / formation of male gonads

SEVE(N) UP

-Seminiferous tubules

-Epididymis

-Vas deferens (ductus deferens)

-Ejaculatory duct

-(Nothing)

-Urethra

-Penis

Mnemonic for memorizing the pathway of sperm through the male reproductive system?

testes

the primitive gonads develop into these

seminiferous tubules and the interstitial cells of Leydig

What are the two functional groups of the testes?

the highly coiled seminiferous tubules

Where is sperm produced?

Sertoli cells

What nourishes sperm?

testosterone and other male hormones (androgens)

What do the cells of Leydig secrete?

scrotum

Where are the testes located?

epididymis

During what part of the pathway does the sperm’s flagella gain motility and the sperm start making extra mitochondria?

seminal fluid

fluid produced by the seminal vesicles, prostate gland, and bulbourethral gland

the seminal vesicles

What contributes fructose to the sperm?

the seminal vesicles and the prostate gland

what gives the sperm mildly alkaline properties so the sperm can survive in the acidity of the female reproductive tract

bulbourethral (Cowper’s) glands

What produces a clear viscous fluid that cleans out any urine and lubricates the urethra during sexual arousal?

semen

the combination of sperm and seminal fluid

spermatogenesis

formation of haploid sperm through meiosis that occurs in the seminiferous tubules

slightly colder

Does spermatogenesis have to occur at a temperature slightly warmer or colder than body temp?

cremaster muscle and dartos muscle

What are the two muscles that allow the scrotum to be raised and lowered based on temp?

spermatic cord

the name for the group of the vas deferens, the artery, and the vein

The mitochondria in the sperm need sugar to make ATP to move

Why is it important that the seminal fluid has fructose for the sperm to pick up before it exits as semen?

Spermatogonium ——> primary spermatocyte ——> secondary spermatocyte ——> spermatid ——> spermatozoan

What is the correct sequence of development of a mature sperm cell?

ovaries

the gonads in a female that produce estrogen and progesterone