Laayla Muhammad
Lab Section: 807
March 10, 2009
Indoleacetic acid (IAA), type of Auxin hormones that promote cell elongation in growing tissues and effect patterns cell differentiation, are used in this experiment on cucumber seedlings to test root growth. The cucumber seedling with IAA concentration of 10.0 mg/L will experience the most root growth because normal amount of concentration of this particular hormone causes stimulation of cell growth; meaning the lower the concentrations, the lower amount of root growth will take place. With the control group having the average root growth of 38.6 mm, the second highest cucumber seedling with the IAA concentration of 10.0 mg/L was 35.5 mm. The seedlings with concentration of 1.0 mg/L and 0.1 mg/L had lower root growths of 17 mm and 9.3 mm and the class average were as followed: the control group averaging out to 38.4 mm, 10.0 mg/L to 36.6 mm, 1.0 mg/L to 23.1 mm, and 0.1 mg/L to 20.3 mm. My hypothesis was right, that besides the control group with the most root growth, as the concentration of IAA increased so did the root growth of the cucumber seedlings; meaning that 0.1 mg/L of concentration was ended up inhibiting the root growth, while concentration of 10.0 mg/L greatly stimulated with 35.5 mm. All of this recorded data agrees with the class average length of the growth roots that also showed as concentration of Auxin increase, so does the length of the cucumber roots, besides the control group which shows cell elongation as well.
Figure 1.1- Average group data used to reveal effects of IAA (type of auxin hormone) given in different concentrations to roots, displaying root elongation (length) in mm.
Gibberellic Acid is one of many types of Gibberellins hormones that promote stem elongation in plants, but has more of a dramatic effect on mutant plants with dwarfed growth. In this experiment, comparing normal and dwarfed plants receiving two different treatments of water and gibberellic acid, I hypothesize that the dwarfed plant with gibberellic acid will experience highest amount of stem elongation meaning it will have the greatest change in height and the dwarfed plant with water will barely grow. The control for the normal plant given just water had the most height change of 20.5 cm and the dwarfed one given just water had the least height change of only 6.90 cm. Normal plant with GA had less change in height (13.5 cm) compared to the dwarfed plan given GA (17.6). The class data shows that normal plants with water grew 14.8 cm and with GA grew 16.8 cm while dwarfed plant with water grew 6.8 cm, but with GA grew 13.4 inches.
Figure 2.1 – Group average used to reveal effects of gibberellic acid (type of gibberellins hormone) on normal and dwarfed plants given two different treatments with their heights being measured in centimeters.
A growth response to gravity, gravitropism, is involved with differential inhibition of cell elongation by the hormone auxin. Gravitropism can be positive where roots grow in the direction of gravity and negative meaning away from the direction of gravity. I hypothesize that the corn seedling planted with the root oriented directly downward will grow the most when compared to: 1) upward, 2) horizontal, and 3) cut off (1 mm) at the root tip and placed horizontally. This is because they will be able to find soil, water and essential minerals easier. Results show that seeds planted downward had a net growth of 2.4 cm with the class average of 3.0 cm, but root planted horizontally grew even more with 3.5 cm. Root placed upward only grew 0.8 and the horizontal root with excited tips did not grow. The class data shows horizontally planted root grew the most with 4.1 cm, but upward one also grew 4.0 cm while the root that was horizontal with its tip excised still grew the least with only 1.2 cm. Roots horizontally orientated experiences the most net growth and planting them upward will result in barely any or no changes. My hypothesis was partially correct since roots planted downward receive essential minerals to grow more than upward positioned roots and roots with excised tips placed horizontally.
Figure 3.1 – Net growth of spouted corn roots measured in centimeters after positioning the roots in four different orientations in order to record root gravitropic response.
Random Rambling Rants
- Laayla
- Houston, Texas, United States
- I'm Laayla. I ramble. I rant. I question. I complain... and sometimes I happen to enlighten.
Monday, May 18, 2009
Lab 9 Manual Study Guide
Development of any complex multicellular organism results from growth processes: Mitosis and cell enlargement and developmental processes f cell differentiation.
In plans, these processes begin from with activities of the meristems….
Growth: increase in size (volume and biomass)
- limited by the supply of resources that are responsible for cell enlargement and division
Development: Changes in form occurring from embryonic stage to adult stages
- under a control of genes directing hormone production, chemicals regulating growth and development
Plants require: water, light, CO2 to make energy-rich sugars and oxygen for cellular respiration
Plants also require mineral nutrients: all essential and lacking them = growth deficiency
- get them from their environment (usually the soil)
Macronutrients: needed in large amounts: Nitrogen, Phosphorus, Potassium, Calcium, Magnesium, and Sulfur
Micronutrients: needed in small amts: Iron, Zinc, Boron, Copper, Manganese, Chlorine, Molybdenum
Lacking particular nutrients = specific growth deficiency
In plans, these processes begin from with activities of the meristems….
Growth: increase in size (volume and biomass)
- limited by the supply of resources that are responsible for cell enlargement and division
Development: Changes in form occurring from embryonic stage to adult stages
- under a control of genes directing hormone production, chemicals regulating growth and development
Plants require: water, light, CO2 to make energy-rich sugars and oxygen for cellular respiration
Plants also require mineral nutrients: all essential and lacking them = growth deficiency
- get them from their environment (usually the soil)
Macronutrients: needed in large amounts: Nitrogen, Phosphorus, Potassium, Calcium, Magnesium, and Sulfur
Micronutrients: needed in small amts: Iron, Zinc, Boron, Copper, Manganese, Chlorine, Molybdenum
Lacking particular nutrients = specific growth deficiency
Lab Practical Overview. Mostly Finished.
Lab Practical Overview:
A. Polifera: Sponges
Q2: Drawing in lab review/notebook. Yes, the spicules are visible. Spicules are the structural support for sponges; they are stiff needles of silica or calcium carbonate.
Q3: They have pores and tubes and structures along with water canals. The water provides the nutrients and oxygen and carries out waste and carbon dioxide. They also have cells with different activities.
1. 4 elements: 0 # of tissues, asymmetrical, N/A, N/A
2. Location & fnx:
a. Tubes on the side are choanocytes (ostia) that move water from the outside to the center
b. osculum where water eventually exists; big opening at end
B. Cnidaria: Hydra, Jellyfish, Corals, Sea Anemones
1. 4 elements: 2 tissues, radial symmetry N/A, N/A
2. Location & Fnx:
a & b: Cnidocytes are specialized cells on tentacles that release stinging organelle called nematocyst (which have toxic barbs to hold prey and until brought to mouth for indigestion).
3. They eat using the process describes above ^
C. Rotifera: Rotifers
Q1: Corona = locomotion & wave food into mouth
Q2: The algae is eaten by the rotifer- it’s their diet plus phytoplankton
1. 4 elements: 3 tissues, bilateral, pseudocoelomate, protostomes
2. Cuticle covering: very close to arthropods and nematodes
3. Location & fnx:
i. Toe (cement glands (sticky) attach rotifer to objects in water)
ii. Corona (crown of celia) – wave food into the mouth, also propel themselves
iii. Celia – rapid movement makes it appear to whirl like a wheel
iv. Excretory system: Intestines
D. Platyhelminthes: Planaria (flat worms)
Q5: Single opening digestive tract visible
Q7: Acoelomate type of body cavity- meaning none
Q8: Protostomes: blastopore developing into the mouth
Q11: Sessile animals have radial symmetry, multidirectional feeding and movement. Motile animals have bilateral symmetry and directional movement to obtain food.
1. 4 elements: 3 tissues, bilateral, acoelomate, protostomes
2. Location & function:
a. a. Pharynx: dorsal part; towards the middle- muscular- has jaws called trophi which ground food- all rotifers have it
b. Flame cells: part of excretory system; move fluid through canals
c. Eyespot: dorsal surface between two auricles that are on the head end; pigmented cups with retinal cells; sensitive to light intensities but can’t form images
E. Annelida: Earthworm (segmented)
Q1: Function of the cuticle in earthworms is that they help with lomotion and since they have no skeleton, cuticle protect them with their bristles like feature
Q2: Advantage of segmentation: Locomotion- each segment has muscles that flex and push against rest of the body, causing the worm to move forward
1. 4 elements: 3 tissues, bilateral, eucoelomate, protostomes
2. Location: heart, crop where the esophagus ends, intestine
Excretory system: Nephridia: pair of tiny white coiled tubes in each segment
F. Mollusca: Clam/Mollusks
1. 4 elements: 3 tissues, bilateral, eucoelomates
2. 4 unifying features: Mantle, Visceral Mass, Foot
3. Location & fnx:
i. Gills: pleated appearance: use for breathing (act like lungs); trap food particles on their surface as water comes in, which is then moved to mouth by ciliary movements.
ii. Mantle: secrets calcium carbonate that produces the shell
iii. Adductor muscles: close the shell and hold it there; anterior and posterior; pink roundish with dots
iv. Foot: strong muscle used for locomotion
v. Incurrent/excurrent siphons: excretory system: incurrent is where water comes in and excurrent is where wastes and water leaves: both at the posterior end of clam…. Excurrent is more dorsal
Lab 13:
A. Nematoda: Nematodes/roundworms (type of Ecdysozoa)
1. 4 elements: 3 tissues, bilateral, pseudocoelum, prostotomes
2. Key characteristics: molting of the exoskeleton (cuticle made of chitin)
3. Morphological differences between male and female are that males are smaller and have a hook like tale they use during sex to hold females
4. Locate and fnx:
i. Uterus: 3rd down, below vagina/tested, in the middle
ii. Testes:
iii. Ovaries: 5th down, 3/4th way down, on top of rectum ***Remember that in nematodes there are two longitudinal tubes in the two lateral lines that are the excretory system: excrete nitrogenous wastes (but no flame cells like flat worms)
B. Arthropoda: Crayfish & Grosshopper:
1. 4 elements: 3 tissues, bilateral, eucoelumate, protostomes
2. 4 unifying characteristics:
3. Location and fnx on Crayfish:
i. Caraspace: expanded exoskeleton plate: feather gills under it
ii. Greenglands: excretory system: long tube-like structures compacted into glandular mass: waste and excess water pass through the pores from which antenna comes out of
4. Location and fnx on Grasshopper:
i. Spiracle: respiratory system: small openings into air tubes (trachea) which branch everywhere and bring oxygen to cells
ii. Malphigian tubules: excretory system: within them are mini tubes that empty into intestine: wastes and salts from blood
iii. Head: Upper part with compound eye, antennas, mouth, brain
iv. Thorax: Middle part: crop, gastric caeca, esophagus, heart,
v. Abdomen: spiracles, intestines, anus, ovary, rectum, ovipositor
Lab 14: Animal Diversity III – Deuterostomes (anus forming first, mouth 2nd)
A. Echinodermata: Sea Stars, sea cucumbers, sea urchins
A. Remember, two symmetry: Radial in adults and bilateral in larvae before metamorphosis.
B. Location and function:
i. Mouth: food/water enterance
ii. 2 stomachs: extending can take place, able to eat bigger stuff than mouth size. Cardiac first and then pyloric.
iii. madreporite: dorsal surface; acts as a water supply and filter
iv. tube feet: movement/feeding; part of vascular water system
B. Chordata: Lancelet, fish, frogs, pigs, humans
A. Four unifying characteristics:
i. Pharyngeal gill slits: openings in the throat
ii. Notochord: running the length of the body
iii. Dorsal hollow nerve cord: bundle of nerve cells running the length of the body as well
iv. A muscular tail – extending past the anus
1. Location and function:
a. Tentacles: for feeding (located on top of the mouth)
b. Mouth: place for water and food (trapped by mucus) to enter body
c. Pharyngeal gill slits: enclosed by the body wall folds, water goes through them and they end up forming a cavity called the atrium
d. Notochord: support along the body length
e. Nerve cord: sensory
f. Intestine: digestion system
g. Anus: place for the wastes to come out of
h. Nephridia: excretory system
Remember, evidence of segmentation: gills, muscles
Evidence of nervous system: nerve cord
2. Location and function:
a. Dorsal fin: movement
b. Nerve cord: sensory
c. Notochord: support
C. Chordata: Pig
1. Location and function:
a. lungs: part of respiratory system: exchange gases
b. heart: pumping blood through blood vessels
c. liver: detoxification, protein synthesis, and production of biochemicals necessary for digestion
d. kidneys: excretory system: reg. of electrolytes, acid-base balance, and blood pressure; excretion of wastes (urea and ammonium); reabsorption of glucose and amino acids; production of hormones (vitamin D and erythropoietin).
e. diaphragm: layer of muscular membrane bottom of thoracic cavity which adjust its volume
f. larynx: protection of trachea and production of sound
g. umbilical cord: connecting cord from the fetus or the embryo to the placenta: supplies oxygenated, nutritious blood
Lab 10 & 11: Animal Development
A. Egg Types:
a. Isolecithal – (same/yolk) – meaning eggs containing small amounts of evenly distributed yolk; impact of yolk is minimum
1. echinoderms, mollusks, and mammals
b. Strongly Telolecithal - (end/yolk) – meaning eggs contain large amounts of yolk concentrated at one end.
1. reptiles, birds, fish, chicken, etc.
2. nucleaus surrounded by active cytoplasm which is devoid of yolk and called blastodisc (towards animal pole where polar bodies budded from the cell during meiosis)
3. Rest of egg: vegetal hemisphere associated with vegetal pole
c. Mesolecithal – moderately telolecithal – some amphibian species
B. 1st Step: Cleavage Types: subsequent mitotic divisions
a. Holoblastic Cleavage: Isolethical eggs
1. The cell divisions pass through the entire fertilized cell
2. blastocoel forms in the middle of the blastula
b. Uneven Holoblastic Cleavage: Moderately Telolecithal:
1. Yolk will retard cytoplasmic divisions and affect cell sizes
2. Blastocoel develops in the animal hemisphere
3. Cells will be smaller and have less yolk compared to vegetal
c. Meroblastic Cleavage: Strongly telolecithal
1. Only active cytoplasm is divided during cleavage
2. produces blastoderm (cap of cells)
3. blastocoel forms between two layers of cells within blastoderm
d. Blastula: multicellular ball/disc that a zygote converts to from cleavage
e. Blastocoel: A cavity that forms within the ball of cells after blastula forms
f. Blastomeres: these are the cells of the blastula
C. Stage 2: Gastrulation: cell movement: blastula becomes gastrula
1. Three germ layers: endoderm (involution) ectoderm (surface cells) mesoderm (develops between the two)
2. Archenteron: new internal cavity that forms through involution, where surface cells go to the interior of the embryo lined by the endoderm: blastocoel disappears
3. Blastopore: what the archenteron opens to the outside through
1. protostomes: blastopore becomes the mouth
2. deuterostomes: blastopore becomes the anus
D. Stage 3: Neurulation: formation of dorsal hollow neural tube in chordates (frogs)
a. Notochord is formed from mesoderm cells
b. Neural plate (ectodermal cells above flattened)
c. neural groove: when the center of the plate sinks
d. neural folds: edges of the plate become elevated
e. neural tube: when folds fuse together; anterior becomes brain and posterior becomes nerve or spinal cord
f. notochord disappears
E. Organgenesis:
a. Organs forming from each tissue layer:
1. Ectoderm: skin, glands, nervous system
2. Mesoderm: muscles, skeleton, circulatory, reproductive and excretory system
1. In chordates, somites and notochord will form as well
3. Endoderm: digestive tract lining and organs: liver and lungs, pancreas, thyroid, thymus, etc
F. Sea Star Development:
a. Type of egg/cleavage: Holoblastic cleavage
b. Fast and slow back to polyspermy (multiple fertilization)
1. fast block: sperm fuses with egg, plasma membrane permeability changes influx of sodium ions [Na+]; changes electric potential ; less permeable
2. slow block: when egg is fertilized, calcium ions release in the ER and spread as a wave, therefore cortical granules fuse with egg cell’s plasma membrane and release their contents to the exterior, causing FERTILIZATION ENVELOPE to rise and clear away extra sperm
c. Know what stages of development listed above look like in the sea star
G. Frog Development:
a. Type of egg/cleavage: uneven holoblastic (moderately telolecithal)
b. Know what stages of development listed above look like in the frog
H. Chicken Development:
a. Egg components:
1. shell membranes
2. albumin
3. chalaza
4. yolk – rich in protein and fat
5. air chamber
b. Embryogenesis in chickens is different from sea star and frog development because: it is through meroblastic cleavage due to being a strong telolecthical type of egg.
c. Know these terms relating to only chicken development:
1. blastodisc - active cytoplasm that is devoid of yolk
2. primitive streak
3. somites
4. vitelline blood vessels
5. 4 extra embryonic membranes
Regeneration:
Morphallixus: regeneration occurring through already present tissues in the organism via reorganization. The regenerated organism is smaller than parent. Examples? 2 Hydra smaller than parents.
Epimorphosis: regeneration occurring through cellular proliferation of stem cells, where the organism is the same size as the parent. Examples? Head in planaria, same size as parents.
A. Polifera: Sponges
Q2: Drawing in lab review/notebook. Yes, the spicules are visible. Spicules are the structural support for sponges; they are stiff needles of silica or calcium carbonate.
Q3: They have pores and tubes and structures along with water canals. The water provides the nutrients and oxygen and carries out waste and carbon dioxide. They also have cells with different activities.
1. 4 elements: 0 # of tissues, asymmetrical, N/A, N/A
2. Location & fnx:
a. Tubes on the side are choanocytes (ostia) that move water from the outside to the center
b. osculum where water eventually exists; big opening at end
B. Cnidaria: Hydra, Jellyfish, Corals, Sea Anemones
1. 4 elements: 2 tissues, radial symmetry N/A, N/A
2. Location & Fnx:
a & b: Cnidocytes are specialized cells on tentacles that release stinging organelle called nematocyst (which have toxic barbs to hold prey and until brought to mouth for indigestion).
3. They eat using the process describes above ^
C. Rotifera: Rotifers
Q1: Corona = locomotion & wave food into mouth
Q2: The algae is eaten by the rotifer- it’s their diet plus phytoplankton
1. 4 elements: 3 tissues, bilateral, pseudocoelomate, protostomes
2. Cuticle covering: very close to arthropods and nematodes
3. Location & fnx:
i. Toe (cement glands (sticky) attach rotifer to objects in water)
ii. Corona (crown of celia) – wave food into the mouth, also propel themselves
iii. Celia – rapid movement makes it appear to whirl like a wheel
iv. Excretory system: Intestines
D. Platyhelminthes: Planaria (flat worms)
Q5: Single opening digestive tract visible
Q7: Acoelomate type of body cavity- meaning none
Q8: Protostomes: blastopore developing into the mouth
Q11: Sessile animals have radial symmetry, multidirectional feeding and movement. Motile animals have bilateral symmetry and directional movement to obtain food.
1. 4 elements: 3 tissues, bilateral, acoelomate, protostomes
2. Location & function:
a. a. Pharynx: dorsal part; towards the middle- muscular- has jaws called trophi which ground food- all rotifers have it
b. Flame cells: part of excretory system; move fluid through canals
c. Eyespot: dorsal surface between two auricles that are on the head end; pigmented cups with retinal cells; sensitive to light intensities but can’t form images
E. Annelida: Earthworm (segmented)
Q1: Function of the cuticle in earthworms is that they help with lomotion and since they have no skeleton, cuticle protect them with their bristles like feature
Q2: Advantage of segmentation: Locomotion- each segment has muscles that flex and push against rest of the body, causing the worm to move forward
1. 4 elements: 3 tissues, bilateral, eucoelomate, protostomes
2. Location: heart, crop where the esophagus ends, intestine
Excretory system: Nephridia: pair of tiny white coiled tubes in each segment
F. Mollusca: Clam/Mollusks
1. 4 elements: 3 tissues, bilateral, eucoelomates
2. 4 unifying features: Mantle, Visceral Mass, Foot
3. Location & fnx:
i. Gills: pleated appearance: use for breathing (act like lungs); trap food particles on their surface as water comes in, which is then moved to mouth by ciliary movements.
ii. Mantle: secrets calcium carbonate that produces the shell
iii. Adductor muscles: close the shell and hold it there; anterior and posterior; pink roundish with dots
iv. Foot: strong muscle used for locomotion
v. Incurrent/excurrent siphons: excretory system: incurrent is where water comes in and excurrent is where wastes and water leaves: both at the posterior end of clam…. Excurrent is more dorsal
Lab 13:
A. Nematoda: Nematodes/roundworms (type of Ecdysozoa)
1. 4 elements: 3 tissues, bilateral, pseudocoelum, prostotomes
2. Key characteristics: molting of the exoskeleton (cuticle made of chitin)
3. Morphological differences between male and female are that males are smaller and have a hook like tale they use during sex to hold females
4. Locate and fnx:
i. Uterus: 3rd down, below vagina/tested, in the middle
ii. Testes:
iii. Ovaries: 5th down, 3/4th way down, on top of rectum ***Remember that in nematodes there are two longitudinal tubes in the two lateral lines that are the excretory system: excrete nitrogenous wastes (but no flame cells like flat worms)
B. Arthropoda: Crayfish & Grosshopper:
1. 4 elements: 3 tissues, bilateral, eucoelumate, protostomes
2. 4 unifying characteristics:
3. Location and fnx on Crayfish:
i. Caraspace: expanded exoskeleton plate: feather gills under it
ii. Greenglands: excretory system: long tube-like structures compacted into glandular mass: waste and excess water pass through the pores from which antenna comes out of
4. Location and fnx on Grasshopper:
i. Spiracle: respiratory system: small openings into air tubes (trachea) which branch everywhere and bring oxygen to cells
ii. Malphigian tubules: excretory system: within them are mini tubes that empty into intestine: wastes and salts from blood
iii. Head: Upper part with compound eye, antennas, mouth, brain
iv. Thorax: Middle part: crop, gastric caeca, esophagus, heart,
v. Abdomen: spiracles, intestines, anus, ovary, rectum, ovipositor
Lab 14: Animal Diversity III – Deuterostomes (anus forming first, mouth 2nd)
A. Echinodermata: Sea Stars, sea cucumbers, sea urchins
A. Remember, two symmetry: Radial in adults and bilateral in larvae before metamorphosis.
B. Location and function:
i. Mouth: food/water enterance
ii. 2 stomachs: extending can take place, able to eat bigger stuff than mouth size. Cardiac first and then pyloric.
iii. madreporite: dorsal surface; acts as a water supply and filter
iv. tube feet: movement/feeding; part of vascular water system
B. Chordata: Lancelet, fish, frogs, pigs, humans
A. Four unifying characteristics:
i. Pharyngeal gill slits: openings in the throat
ii. Notochord: running the length of the body
iii. Dorsal hollow nerve cord: bundle of nerve cells running the length of the body as well
iv. A muscular tail – extending past the anus
1. Location and function:
a. Tentacles: for feeding (located on top of the mouth)
b. Mouth: place for water and food (trapped by mucus) to enter body
c. Pharyngeal gill slits: enclosed by the body wall folds, water goes through them and they end up forming a cavity called the atrium
d. Notochord: support along the body length
e. Nerve cord: sensory
f. Intestine: digestion system
g. Anus: place for the wastes to come out of
h. Nephridia: excretory system
Remember, evidence of segmentation: gills, muscles
Evidence of nervous system: nerve cord
2. Location and function:
a. Dorsal fin: movement
b. Nerve cord: sensory
c. Notochord: support
C. Chordata: Pig
1. Location and function:
a. lungs: part of respiratory system: exchange gases
b. heart: pumping blood through blood vessels
c. liver: detoxification, protein synthesis, and production of biochemicals necessary for digestion
d. kidneys: excretory system: reg. of electrolytes, acid-base balance, and blood pressure; excretion of wastes (urea and ammonium); reabsorption of glucose and amino acids; production of hormones (vitamin D and erythropoietin).
e. diaphragm: layer of muscular membrane bottom of thoracic cavity which adjust its volume
f. larynx: protection of trachea and production of sound
g. umbilical cord: connecting cord from the fetus or the embryo to the placenta: supplies oxygenated, nutritious blood
Lab 10 & 11: Animal Development
A. Egg Types:
a. Isolecithal – (same/yolk) – meaning eggs containing small amounts of evenly distributed yolk; impact of yolk is minimum
1. echinoderms, mollusks, and mammals
b. Strongly Telolecithal - (end/yolk) – meaning eggs contain large amounts of yolk concentrated at one end.
1. reptiles, birds, fish, chicken, etc.
2. nucleaus surrounded by active cytoplasm which is devoid of yolk and called blastodisc (towards animal pole where polar bodies budded from the cell during meiosis)
3. Rest of egg: vegetal hemisphere associated with vegetal pole
c. Mesolecithal – moderately telolecithal – some amphibian species
B. 1st Step: Cleavage Types: subsequent mitotic divisions
a. Holoblastic Cleavage: Isolethical eggs
1. The cell divisions pass through the entire fertilized cell
2. blastocoel forms in the middle of the blastula
b. Uneven Holoblastic Cleavage: Moderately Telolecithal:
1. Yolk will retard cytoplasmic divisions and affect cell sizes
2. Blastocoel develops in the animal hemisphere
3. Cells will be smaller and have less yolk compared to vegetal
c. Meroblastic Cleavage: Strongly telolecithal
1. Only active cytoplasm is divided during cleavage
2. produces blastoderm (cap of cells)
3. blastocoel forms between two layers of cells within blastoderm
d. Blastula: multicellular ball/disc that a zygote converts to from cleavage
e. Blastocoel: A cavity that forms within the ball of cells after blastula forms
f. Blastomeres: these are the cells of the blastula
C. Stage 2: Gastrulation: cell movement: blastula becomes gastrula
1. Three germ layers: endoderm (involution) ectoderm (surface cells) mesoderm (develops between the two)
2. Archenteron: new internal cavity that forms through involution, where surface cells go to the interior of the embryo lined by the endoderm: blastocoel disappears
3. Blastopore: what the archenteron opens to the outside through
1. protostomes: blastopore becomes the mouth
2. deuterostomes: blastopore becomes the anus
D. Stage 3: Neurulation: formation of dorsal hollow neural tube in chordates (frogs)
a. Notochord is formed from mesoderm cells
b. Neural plate (ectodermal cells above flattened)
c. neural groove: when the center of the plate sinks
d. neural folds: edges of the plate become elevated
e. neural tube: when folds fuse together; anterior becomes brain and posterior becomes nerve or spinal cord
f. notochord disappears
E. Organgenesis:
a. Organs forming from each tissue layer:
1. Ectoderm: skin, glands, nervous system
2. Mesoderm: muscles, skeleton, circulatory, reproductive and excretory system
1. In chordates, somites and notochord will form as well
3. Endoderm: digestive tract lining and organs: liver and lungs, pancreas, thyroid, thymus, etc
F. Sea Star Development:
a. Type of egg/cleavage: Holoblastic cleavage
b. Fast and slow back to polyspermy (multiple fertilization)
1. fast block: sperm fuses with egg, plasma membrane permeability changes influx of sodium ions [Na+]; changes electric potential ; less permeable
2. slow block: when egg is fertilized, calcium ions release in the ER and spread as a wave, therefore cortical granules fuse with egg cell’s plasma membrane and release their contents to the exterior, causing FERTILIZATION ENVELOPE to rise and clear away extra sperm
c. Know what stages of development listed above look like in the sea star
G. Frog Development:
a. Type of egg/cleavage: uneven holoblastic (moderately telolecithal)
b. Know what stages of development listed above look like in the frog
H. Chicken Development:
a. Egg components:
1. shell membranes
2. albumin
3. chalaza
4. yolk – rich in protein and fat
5. air chamber
b. Embryogenesis in chickens is different from sea star and frog development because: it is through meroblastic cleavage due to being a strong telolecthical type of egg.
c. Know these terms relating to only chicken development:
1. blastodisc - active cytoplasm that is devoid of yolk
2. primitive streak
3. somites
4. vitelline blood vessels
5. 4 extra embryonic membranes
Regeneration:
Morphallixus: regeneration occurring through already present tissues in the organism via reorganization. The regenerated organism is smaller than parent. Examples? 2 Hydra smaller than parents.
Epimorphosis: regeneration occurring through cellular proliferation of stem cells, where the organism is the same size as the parent. Examples? Head in planaria, same size as parents.
Chapter 4 Outline - Not complete....
Chapter 4 outline: Role of Foundation Support
Scientists viewed as individuals with massive talents in order to receive financial banking
• Nonscientists impressed even though they didn’t comprehend yet thought science = knowledge and power
Blacks did not benefit: Only white universities provided the extensive education and right training
- Accepted on exceptional cases; not able to find jobs if given chance; led to just work as teachers in a black university
- Philanthropic establishments didn’t even want think black colleges deserved to receive any support because the training they provide for scientists and the high quality research they provide isn’t a good investment
**With hardly any support, it became hard for blacks to pursue careers in the scientific field
Howard University; not set up for blacks alone; opened door to 4 white girls as well
- Purpose: All races, classes, conditions, and nationalities” – term refer cosmopolitan
- Not achieved; whites dropped
- Poor institution; 1st funds were from Bureau of Refugees (freedman and abandoned lands set up by congress after the civil war to aid free slaves)
- 1873: nation crippled financially and funds stopped
- White staff with black service; first 12 presidents = northerners connected to churches
- Black intelligent men/respected professors trained at white colleges yet worked at black institutions; Howard comes into play because it was still growing in numerous ways
- “Howard Univ. for Maintenance” – Congress gave 10,000/100,000 debt – small gift increased every year
***Wilbur P. Thirkield: New Building in 1909; recruit scientists; school for blacks migrating to cities; Just entered in time!
1. 1910: Flexnor Report: Howard and Meharry respected; helped with grants
2. World Leaders of government/education made speeches on Howard’s behalf
3. Just wanted to find funds partly out of selfish reasons; salary/summer research
WWI:
Howard = best place for recruits and commissioned officers
Just: did not want to take orders from white officers or less educated men; war horrified him; increased his teachings in electrocardiography to avoid war
Durkee presidency: gave just a knuckle-rapping for not attending morning prayers; not sympathetic to the scientific development
Charity confused with Philanthropy; Just founded funds
Scientists viewed as individuals with massive talents in order to receive financial banking
• Nonscientists impressed even though they didn’t comprehend yet thought science = knowledge and power
Blacks did not benefit: Only white universities provided the extensive education and right training
- Accepted on exceptional cases; not able to find jobs if given chance; led to just work as teachers in a black university
- Philanthropic establishments didn’t even want think black colleges deserved to receive any support because the training they provide for scientists and the high quality research they provide isn’t a good investment
**With hardly any support, it became hard for blacks to pursue careers in the scientific field
Howard University; not set up for blacks alone; opened door to 4 white girls as well
- Purpose: All races, classes, conditions, and nationalities” – term refer cosmopolitan
- Not achieved; whites dropped
- Poor institution; 1st funds were from Bureau of Refugees (freedman and abandoned lands set up by congress after the civil war to aid free slaves)
- 1873: nation crippled financially and funds stopped
- White staff with black service; first 12 presidents = northerners connected to churches
- Black intelligent men/respected professors trained at white colleges yet worked at black institutions; Howard comes into play because it was still growing in numerous ways
- “Howard Univ. for Maintenance” – Congress gave 10,000/100,000 debt – small gift increased every year
***Wilbur P. Thirkield: New Building in 1909; recruit scientists; school for blacks migrating to cities; Just entered in time!
1. 1910: Flexnor Report: Howard and Meharry respected; helped with grants
2. World Leaders of government/education made speeches on Howard’s behalf
3. Just wanted to find funds partly out of selfish reasons; salary/summer research
WWI:
Howard = best place for recruits and commissioned officers
Just: did not want to take orders from white officers or less educated men; war horrified him; increased his teachings in electrocardiography to avoid war
Durkee presidency: gave just a knuckle-rapping for not attending morning prayers; not sympathetic to the scientific development
Charity confused with Philanthropy; Just founded funds
Wednesday, May 13, 2009
Wednesday, May 06, 2009
UNICEF - Child protection from violence, exploitation and abuse - UN Security Council addresses latest report on children in armed conflict
UNICEF - Child protection from violence, exploitation and abuse - UN Security Council addresses latest report on children in armed conflict
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