T3: Spermatozoa/ Sperm Charcaterisitcs

Question 1

what parts make up the sperm

Answer 1

head and tail

Question 2

what makes up the head in the sperm?

Answer 2

nucleus, acrosome, post nuclear cap

Question 3

what makes up the tail in the sperm?

Answer 3

middle piece, principal piece, and terminal piece

Question 4

what part has different characteristics for each species

Answer 4

the head, some tail variations

Question 5

name the basic components of the sperm

Answer 5

acrosome and nucleus in the head, then the neck, mitochondrion(middle piece), plasma membrane, and tail

Question 6

describe the nucleus of the head

Answer 6

-oval, flattened
-genetic material is nearly inert due to high degree of keratinization (disulfide cross-linking)

Question 7

what happens in the nucleus of the head at fertilization

Answer 7

disulfide cross links are reduced by glutathione in cytoplasm of oocyte

Question 8

what is the acrosome and what is the importance

Answer 8

-covers the anterior 2/3 of the nucleus
-membrane-bound lysosome that contains hydrolytic enzymes

Question 9

what is the post nuclear cap

Answer 9

-membrane component posterior to the acrosome

Question 10

describe the sperm head anatomy

Answer 10

at the top there is the apical ridge(enzymes are found here) following is the acrosome, then post nuclear cap, the nuclear ring/ equatorial ring separates the two regions, the plasma membrane surrounds the entire head and in the center is the nucleus

Question 11

what are the two acrosomal enzymes

Answer 11

acrosin, hyaluronidase

Question 12

where are the disulfide bonds

Answer 12

nucleus

Question 13

what makes up the middle piece of the tail

Answer 13

-mitochondria: arranged in a helical structure
-laminated columns: flexibility for movement
-9 coarse fibers
-9 pairs of microtubules around 2 central filaments

Question 14

what are the laminated columns, mitochondrial helix, and axoneme used for

Answer 14

flexibility, energy, and bending

Question 15

what causes movement of the sperm

Answer 15

axoneme, motor proteins connecting the microtubules, allow the tail to bend and move the sperm through the repro tract

Question 16

T/F the axoneme stretches through the entire tail

Answer 16

true

Question 17

T/F the mitochondria are only contained in the middle piece

Answer 17

true

Question 18

describe the components of the axoneme/ important motor proteins and their role

Answer 18

-Radial Spokes: that connect the microtubule inward (outer to center)
-Dynein arms: help with flagella movement(small stem like protrusions form the tubule) MOVEMENT
-Nexin: Anchoring protein, helps keep the outer tubes connected

Question 19

describe the microtubule sliding in sperm tail

Answer 19

1. Dynein arm elongated and attached (no ATP rigor)
2. Dynein arm detaches and shortens(ATP release)
3. Dynein arm tilts, elongates and attaches at lower site (ATP to ADP + energy/ re-extension/binding)
   4.Dynein arm shortens and returns to horizontal “rigor” (elevation to sliding)
   noted as walking up and down the pairs of microtubules

Question 20

Describe the microtubule arrangement

Answer 20

2 central (singlet microtubules) to 9 microtubule doublets
- flagella can have portions of the tubule in different states and this is what gives it the shape
(9,9,2 arrangement of the axoneme)

Question 21

what follows after the posterior head and is before the laminated columns (start of the middle piece)

Answer 21

capitulum

Question 22

what is the juncture between the middle pieces and the principal piece

Answer 22

the annulus

Question 23

what is the majority of the tail

Answer 23

principial piece

Question 24

where is the fibrous helix found

Answer 24

in the principal piece, which is above the terminal piece

Question 25

describe the subsections of the sperm

Answer 25

1. Head: acrosome, neck/ capitulum 2.Tail -Capitulum, midpiece, principal piece, and terminal piece -the capitulum fits into the implantation socket -annulus is separating the midpiece from the principal piece

Question 26

where do microtubules end

Answer 26

in the terminal piece

Question 27

what is the primary energy supply for sperm

Answer 27

glucose

Question 28

describe the ATP utilization in sperm

Answer 28

- motility (60%) -substrate cycling (40%): wasted -maintenance of ionic gradients: very small amount -no transcription and translation: none after condensation of nucleus and loss of residual body(cytoplasmic droplet)

Question 29

what is sperm metabolism dependent on

Answer 29

-temperature (movement of flagella) -ATP production increases as temperature increases -ATP dependent processes are temp dependent -motility increases with increasing temperature -beat frequency increases with temp increase

Question 30

how is sperm transported? what does each region do?

Answer 30

1. vas efferentia: fluid flow/ cilia 2. vas deferens: contractions 3. corpus: contractions 4. cauda: contractions 5.semiferous tubule: bulk fluid flow, contractions of myoid cells 6. rete testis: fluid flow, RT secretion 7. Caput: contractions

Question 31

what is the epididymal function

Answer 31

-change in fertility -develop motility -nuclear condensation -cytoplasmic droplet -increase disulfide crosslinking -transport/ maturation mainly

Question 32

what is the importance of a breeding soundness exam

Answer 32

ensures the male is ready to breed/ security blanket

Question 33

what are the ejaculate characteristics of the species

Answer 33

bull-1 sec- single fraction ram- 1 sec- single fraction boar- 5-25 minutes- fractionated sperm free/ sperm rich coagulum stallion-30-60 seconds- fractionated sperm free/ sperm rich mucus human- 10-30 seconds- single fraction but coagulated

Question 34

what are the things tested during a initial semen evaluation

Answer 34

color, volume, (visual) concentration, motility, viability, morphology

Question 35

what is the typical semen color and volume

Answer 35

-color : white to cream color is good yellow: urine is present clear or thin: few sperm -volume: weight 1ml to 1 gm -concentration hemocytometer: gold standard spectrophotometer, photometer, fluorometer (measure DNA)

Question 36

What are the components to a motility evaluation

Answer 36

-also a viability evaluation -visual estimation (nearest 5% estimate) -total motility: all moving sperm -progressive motility: sperm moving in a straight line -CASA: computer aided sperm analysis -tracts individual sperm and computes a variety of stats

Question 37

what is key to usefulness of data obtained

Answer 37

sample preparation

Question 38

what does the color of the green florescent sperm in the viability assay mean? red?

Answer 38

red is dead green is viable

Question 39

what are the different sample preparations and methods for evaluation

Answer 39

-stain vs. no stain -wet mount vs. dried or fixed -magnification of observation -computer systems require training samples

Question 40

what are in scheme A of morphology classifications

Answer 40

primary: head abnormalities secondary: tail abnormalities

Question 41

what are in the scheme B of morphology classifications

Answer 41

Primary: head secondary: tail Tertiary: cytoplasmic droplets

Question 42

what type of defects are the most concerning

Answer 42

proximal are the most concerning

Question 43

what are the percent normal ranges for species

Answer 43

bull: 95 ram:95 boar: 90 stallion: 40-90 man: 30-70