Chapter 7 part 1

Question 1

Urge and Urge and Urge, always the procreant urge of the world. Out of the dimness opposite equals advance, always substance and increase, always sex, always distinction

Answer 1

Walt Whitman

Question 2

Fertiliation is not a moment or an event but a process of carefully orchestrated and coordinated events, including the contact and fusion of gametes, the fusion of pronuclei, and the activation of development. It is a process whereby two cells, each at the verge of _______ to create a new organism that will have numerous cell types and organs. It is just the beginning of a series of cell-cell interactions that characterize animal development

Answer 2

verge of death, unite

Question 3

_______: The fusion of two sex cells to form a new genetically unique individual

Answer 3

fertilization

Question 4

Fertilization accomplishes two major goals:

Answer 4

1) sexual recombination
2) reproduction

Question 5

_______: combines genetic information from both parents in a new way

Answer 5

sexual recombination

Question 6

_______: creates a new organism

Answer 6

reproduction

Question 7

Fertilization proceeds through 4 major events:
1) _______ and recognition between sperm
2) _______ of sperm entry into oocyte
3) _______of genetic material contributed by sperm and egg
4) _______ of metabolism within the egg to begin development

Answer 7

1) contact
- ensures that only one species is involved
2) regulation
- ensures only 1 sperm is allowed in
3) fusion
4) activation

Question 8

Sperm are produced through the modification of a germ-line cell:
1) virtually all _______ is lost
2) _______ condenses into a very compact form
3) a single ______ is produced

Answer 8

1) cytoplasm
2) nucleus
3) flagella

Question 9

What are the 3 regions of a sperm?

Answer 9

1) head region
2) midpiece
3) tail

Question 10

Head region:
Acrosomal vesicle sac of enzymes that digest _______ and _______

Answer 10

proteins and sugars

Question 11

In the head region, the nucleus is _______ and _______, surrounded by very little cytoplasm

Answer 11

compact
haploid

Question 12

Midpiece:
_______ organize and orient microtubules of the Axoneme

Answer 12

centriole

Question 13

Midpiece:
_______: central core of microtubules in flagella

Answer 13

axoneme

Question 14

Midpiece:
Multiple _______ are arranged in rings around the axoneme and surrounded by a tough sheath

Answer 14

mitochondria

Question 15

Tail:
single _______ to provide movement. Whips _______ and _______

Answer 15

flagellum
- eukaryotic flagella whip back and forth

Question 16

What is the difference between egg and oocyte?

Answer 16

• egg is gamete capable of binding sperm
• oocyte is developing egg that isnt ready for fertilization

Question 17

Unlike sperm, eggs accumulate large volumes of _______

Answer 17

cytoplasm

Question 18

Eggs contain:
1) _______ nutritive and energy supply
2) _______, which allow large burst of protein synthesis immediately following fertilization
3) _______ which provide early instructions for egg development, thousands of _______ stored in some species
4) _______ direct early differentiation, often sequestered in different regions of cytoplasm
5) _______ act as UV filters, DNA repair enzymes, antibodies, distasteful compounds

Answer 18

1) proteins
2) ribosomes and tRNA’s
3) mRNA’s
4) morphogenic factors
5) protective chemicals

Question 19

Depending on the species, the egg may or may not have completed _______ prior to sperm entry

Answer 19

meiosis II

Question 20

_______ finished all stages prior to sperm entry, while _______ egg remains in metaphase of meiosis II until sperm entry, then meiosis completes just prior to fusion of male and female pronuclei

Answer 20

Sea urchin
Human

Question 21

_______ regulates ion and substance flow into/out of egg

Answer 21

cell (plasma) membrane

Question 22

_______ fibrous extracellular mat outside of membrane that is rich in glycoproteins

Answer 22

vitelline envelop
- zona pellucida in mammals

Question 23

_______ cells: remnants of ovarian follicle cells that nuture and protect the egg following release from ovary inner layer

Answer 23

cumulus
- corona radiata

Question 24

_______: outside of vitelline envelop, rich in glycoproteins also involved in attracting and activating sperm

Answer 24

Egg jelly layer (jelly coat)

Question 25

_______: thin layer of gel-like cytoplasm immediately inside cell membrane

Answer 25

cortex

Question 26

The egg cortex contains high concentrations of _______ that polymerize to form _______ that may aid sperm entry

Answer 26

actin microvilli

Question 27

The egg cortex contains thousands of _______, which is analogous to acrosomal vesicle of sperm

Answer 27

cortical granules

Question 28

Cortical granules of egg are derived from _______

Answer 28

Golgi

Question 29

Cortical granules contain _______ enzymes, adhesive _______, _______, and _______ protein

Answer 29

proteolytic glycoproteins mucopolysaccharides hyalin

Question 30

The 5 major steps to egg and sperm recognition: 1) _______ of the sperm to the egg 2) _______ of the sperm acrosomal vesicle 3) _______ of the sperm to the extracellular matrix of the egg 4) _______ of the sperm through this extracellular matrix 5) _______ of the egg and sperm membranes

Answer 30

1) chemoattraction 2) exocytosis 3) binding 4) passage 5) fusion

Question 31

Sperm swimming towards soluble chemicals released by the egg is an example of _______

Answer 31

chemotaxis

Question 32

_______: 14-aa peptide in sea urchins, which does not attract sperm from other species

Answer 32

Resact

Question 33

Describe the process of sperm attraction to the egg via Resact (4)

Answer 33

1) Resact binds to receptor Guanylyl cyclase (RGC) on sperm 2) RGC converts GTP to cGMP 3) cGMP opens up Ca2+ channel 4) Ca2+ enters, providing directional cue for sperm

Question 34

Along with its attraction characteristic, Resact also functions as a _______, by stimulating **mitochondrial production of ATP** and the **dynein ATPase** required for flagella movement

Answer 34

sperm-activating peptide

Question 35

The acrosomal reaction is **initiated** by contact with species-specific _______ within the egg jelly, which also acts as a barrier to prevent **interspecific fertilization**

Answer 35

sulfated-polysaccharides

Question 36

Describe the process (part 1) of releasing the contents of the acrosomal vesicle (3)

Answer 36

1) Activation of Ca2+ channels (Ca into cell) 2) Activation of Na+/H+ antiporters (Na+ into, H+ out) 3) Activation of Phospholipase (produces IP3)

Question 37

During the acrosomal reaction, the increase of intracellular Ca2+ triggers the fusion of the _______ membrane with the _______ membrane releasing its proteolytic enzymes onto the surface of the egg

Answer 37

acrosomal vesicle sperm cell

Question 38

The acrosomal process is a rigid structure created by the polymerization of _______ into actin microfilaments

Answer 38

globular actin

Question 39

The increase in Ca2+ activates _______, a GTP-binding protein that mediates the polymerization of actin

Answer 39

RhoB - helps create the acrosomal process - activated when GTP is bound

Question 40

The acrosomal process is covered with _______, a large species-specific protein

Answer 40

bindin

Question 41

Sperm binding does not occur all over the egg, but appears to be limited to sites containing large numbers of bindin receptors. In **sea urchins** the protein is _______

Answer 41

EBR1 - thought to be

Question 42

What are the 3 sperm-egg specificity mechanisms in sea urchins?

Answer 42

1) resact (chemoattractant) 2) sulfated-polysaccharide (starts acrosomal RXN, found in jelly) 3) bindin receptor (EBR1)