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When Quagmire was asked for his opinion on the up coming test his reply: "Jiggidy, jiggidy, jiggidy OH YEAH!!!!"


Bulletin Board

I have know put up all notes to this point. Keep checking over the weekend as I will provide some helpful hints on what to study.


Chemistry, The Only Science That Really MATTERS!!!!!


All notes and assignemnts that you may have missed. Plus practice sets, quizzes, and tests.



Exploring the Modern Periodic Table

Activity 4.3

1a) All symbols that are coloured red are gases at room temperature (H, He, N, O, F, Ne, Cl, Ar, Kr, Xe, Rn)

b) All symbols that are coloured blue are liquids at room temperature (Hg, Br)

2a) 2 b) 79 c) V d) As

3a) 27 b) 108 c) Ca d) Kr

4a) Tellurium and Iodine (127.6 : 126.9)

5a) Carbon is the highest melting temperature at 3550 0c

b) Helium has the lowest melting temperature at -272 0c

c) Osmium at 22.5 g/cm3 has the greatest density

d) Hydrogen at 0.09 g/cm3 has the lowest density

6b) All have 1 valence e-

c) Rb and Cs both contain 1 valence e-

7b) Both elements have 7 valence e-

c) Both elements have 7 valence e-

8b) As you move across a row the outer orbital fills up one e- at a time

9i) H4Si ii) H3P iii) H2S


Understanding Concept Questions

1) Most elements exist in solid state at room temperature

2a) Atomic # increases as you move left to right

b) Melting point increases as you move left to right

c) Atomic radius decreases as you move left to right

3a) Density increases as move down the column

b) Melting point increases as you move down the periodic table (this is a very flawed generalization)

c) Atomic radius increases as you move down the columns



Sexual Reproduction and the Diversity of Life

Reproduction:
- Reproduction is the creating of new life and happens in many different ways

Asexual Reproduction:
- One parent and its offspring are genetically identical

Sexual Reproduction:
- Sexual reproduction is common for multicellular organisms
- 2 parents for offspring
- Offspring are not genetically identical to either parent, instead they are a combination of the two
- In complex animals, specialized sex cells are usually the means by which genetic information is passed along
- Specialized sex cells in males are typically sperm and females are eggs, these combine to form a zygote (Zygote is a fertilized egg cell)
- Sexual reproduction produces new combinations of genes ensuring that no two sexual offspring are identical
- This form of reproduction also allows for environmental changes making offspring more suited to the environment

Conjugation
- bacteria typically reproduce asexually but they due also reproduce sexually, this is Conjugation
- two cells come in contact with each other and exchange small pieces, rarely all, of their genetic information
- conjugation increases the diversity of bacteria and helps to create super bacteria

Hermaphrodites:
- Sexual reproduction is difficult for organism that have restricted movement as they are unable to reach a partner (eg sponges and tomatoes)
- Solution to this is hermaphroditic reproduction, or a species that creates both male and female sex cells
- These creatures create both sperm of the male and eggs of the female
- In some cases hermaphrodites can join together and deposit sperm into the other animal (worms)
- Animal hermaphrodites release sperm into the water at a certain time every year
- Plants release pollen or have it carried by bees or other insects

Separate Sexes:
- Most animals and some plants have separate sexes (males and females)
- Males produce sperm and females produce eggs
- The determination of male and female in humans is found in the chromosomes, called the X and Y
- Females (humans) have a pair of X chromosomes in each cell (one from each parent)
- Males have a single X chromosome (from mother) and a much smaller Y chromosome (from father) in each cell
- Fertilization takes place in 2 different methods: Internal and External fertilization
* Internal: male deposits sperm inside the body of the female, eg dogs
* External: male releases sperm after female has released eggs. The sex cells unite out of the female body, eg fish


Chromosome Number and the Formation of Sex Cells

- Human cells contain 46 chromosomes. If these 46 chromosomes paired with another 46 chromosomes you would have 96, and then 192, etc.

- The process that forms sex cells is meiosis. During Meiosis the chromosome number is cut in half to23 chromosomes
- The 46-chromosome number is referred to as the diploid chromosome #, and is written as 2n
- The 23-chromosome # is referred to as the haploid chromosome # and is given the symbol n
- A haploid sperm cell and a haploid egg cell will create a diploid zygote

Aphids: Both Sexual and Asexual

- Aphids are the tiny little insects you may see underneath a leaf in the spring time

- Female aphids during the summer months will give birth asexually to female aphids
- The newborn aphids have unfertilized eggs that will start to develop into other female aphids (almost like summer aphids are born pregnant)
- In the fall when temperatures start to get cooler, some of the female aphids turn into males (scientist unsure how this process takes place)
- The new males fertilize female eggs that can survive over the winter
- These offspring carrier genetic information from both parents


Sex Cell Development in Males

Structure of Sperm:
- The sperm cell is designed for the purpose of motion
- Reduced cytoplasm surrounds the nucleus, this is beneficial for a cell that must move but presents a problem as it has a limited energy reserve

Sperm Production and Development:
- Testis is primary reproductive organ of the male mammal
- Testis produce and nourish the sperm as they mature
- The insides of the testis are filled with tiny, twisting tubes; these seminiferous tubules are lined with reproductive cells that produce sex cells through meiosis
- Human reproductive cells are diploid while the mature human sperm are haploid
- Sperm are not built to last, those that are not used die after several days and are replaced by newer cells from the testes

Fertilization:
- In mammals fertilization is internal, each egg is fertilized by one sperm
- The sperms uses its stored energy to enter the egg, though only the head of the sperm is permitted to enter, the body remains out side
- As soon as one sperm enters, the egg puts up a barrier so that other sperm cannot enter

- Once inside the egg, the sperms nucleus merges with the nucleus of the egg

Hormones and Male Sex cell Production:
- Not until week 7 of fertilization is there any differences b/w male and female embryos
- Week 7 a chemical messenger ( a hormone) is sent from the brain to stimulate the development of sexual structures
- After birth both male and female sex organs produce very low levels of sex hormones
- These sex hormones continue to play a role in development of characteristics but reproductive organs are not capable of producing mature sex cells until puberty
- Puberty is a stage of rapid growth and sexual maturity that typically takes place b/w the ages of 9 -15
- During this time, the amount of testosterone produced increases which stimulates sperm development

- Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH) are both hormones released by the brain and are important in the development of testosterone and sperm

Questions # 1-6, pg. 215

Sex Cell Development in Females

In humans the female reproduction organs are far more complex then those of males because is has the responsibility of nurturing the embryo.

Structure of the Egg:
- The egg is much larger then sperm and is packed with nutrients so when it is fertilized it can divide rapidly
- After fertilized it has the ability to build a barrier from other sperm
- Millions of sperm are produced daily by males, females usually develop one egg at a time

Production and Development of the Egg:
- Primary reproductive organ of the female is the ovary, it is responsible for producing and developing egg cells
- The ovary contains the follicles
- Follicles are composed of 2 types of cells: reproductive cells and nutrient producing cells (creates energy rich chemicals)
- Human ovary contains about 400,000 immature follicles at puberty, this # continually decreases
- Hundreds of follicles develop every cycle but normally only a single follicle is allowed to reach maturity in each cycle
- As follicles develop, they go through meiosis, which forms one large egg with 23 chromosomes and three smaller eggs that disintegrate
- When the nutrient eggs are ready the ovary will; burst and the egg cell is released into the oviduct, the release process is called ovulation
- Nutrient cells that remain in the ovary are transformed into a tissue called corpus luteum which secretes hormones that are essential for pregnancy
- If fertilization does not occur then after 10 days the cycle that leads to ovulation begins again

Pregnancy:
- If an egg is fertilized by a sperm cell while moving through the oviduct, the zygote divides by mitosis becoming an embryo
- If the egg is not fertilized then it is shed in a process called menstruation

The Role of Hormones:
- Females in puberty, the pituitary gland in the brain secretes two hormones, FSH & LH, which stimulate the changes that take place in the female body
- Hormones are also responsible for the development of internal and external sexual organs

Estrogen:
- FSH triggers the development of follicle cells in the ovary
- As ovaries develop they secrete estrogen
- Estrogen encourages the endometrium to thicken in preparation for the zygote

Hmwk: pg. 218# 1-8


- The arrow follows the ovarian follicles from their maturation (primary follicles) to their eventual demise as Corpus Luteum. Of Note: the follicle do not actually move instead this diagram is just to show the progression of the follicles.
- Women produce estrogen from two places: ovary follicles and fat cells.
- As a follicle grows, the egg enlarges to about 150 microns (grain of sand)
- Before the age of 30 most women multiple eggs get ready to ovulate and form follicles on the ovary. One follicle becomes dominant and ruptures and the egg is released, all the other follicles become smaller and disappear. The rupture follicle is called the Corpus Luteum.


Atypical Meiosis

- If an error occurs during division of a somatic cell (ex. skin or liver) it may not hurt the organism.
- If something goes wrong with during Meiosis in a reproductive cell the resulting embryo is in serious trouble
- Nondisjunction (failure to separate) is an error that occurs when 2 homologous chromosomes move to the same pole during meiosis
- The result is that one of the daughter cells is missing a chromosome while the other has an extra chromosome
- Cells that lack or have to much genetic information will not function properly
- In humans, nondisjunction can produce sex cells with 22 or 24
chromosomes
- The sex cell with 24 chromosomes has both chromosomes from one of the homologous pairs. If this sex cell joins with a normal sex cell, the zygote will have 47 chromosomes, if the sex cell only has 22 then the zygote will have 45
- When the fertilized egg with an abnormal # of chromosomes begins to divide each cell in the body will have this abnormal # of chromosomes
- In most cases the zygote will die if there is too many abnormalities, in a few cases a person with a nondisjunction is born

Nondisjunction Disorders
- Down syndrome is a genetic disorder produced by nondisjunction
- Most people with down syndrome have an extra chromosome on the 21 pair, an ex of too much information
- The multi capabilities of a person with Down syndrome varies greatly form individual to individual, with severities differing
- It is estimated that 1/600 children are born with Down Syndrome

Turner Syndrome:
-Turner syndrome occurs when either sex chromosomes undergo nondisjunction in either the male or female parent
- This produces a female with a single x chromosome instead of 2
- Females with turners will never reach maturity and are shorter in height then the average women
- Turner syndrome effects 1/10 000 females

Klinefelter syndrome
- Is a nondisjunction caused by either the male or female sex cell
- The child receives two X chromosomes and one Y chromosome
- The child is a male, but with the onset of puberty they start producing high levels of female sex hormones, making it impossible for them to father children
- Klinefelter effects 1/1000 males

Questions pg. 223 #1 - 7


Sex Chromosomes

The nuclei of human cells contain 22 autosomes and 2 sex chromosomes. In females, the sex chromosomes are the 2 X chromosomes. Males have one X chromosome and one Y chromosome. The presence of the Y chromosome is decisive for unleashing the developmental program that leads to a baby boy.

The Y Chromosome (copy starting here)
- In making sperm by meiosis, the X and Y chromosomes must separate in anaphase
- Most of the time this occurs without a problem during the prophase of meiosis I

Pseudoautosomal Regions
- These are located at opposite ends of the chromosome.
- The pseudoautosomal regions are inherited just like any autosomal genes
- Males have two copies of these genes: one in the pseudoautosomal region of their Y, the other in the corresponding portion of their X chromosome
- 95% of the Y chromosome lies b/w the pseudoautosomal regions,
- The others encode proteins function only in the testes. A key player in this group is SRY.

SRY
- SRY (for sex-determining region Y) is a gene located on the short (p) arm just outside the pseudoautosomal region
- It is the master switch that triggers the events that converts the embryo into a male, without this gene, you get a female instead

* On very rare occasions aneuploid humans are born with such karyotypes as XXY, XXXY, and even XXXXY. Despite their extra X chromosomes, all these cases are male.

In the study of mice:

Mice will have testes, male sex hormones, and normal mating behavior, they are sterile.
* Another rarity: XX humans with testicular tissue because a translocation has placed the SRY gene on one of the X chromosomes
* Still another rarity that demonstrates the case: women with an XY karyotype who, despite their Y chromosome, are female because of a destructive mutation in SRY.

(A test based on a molecular probe for SRY was used to ensure that potential competitors for the women's Olympic events in Atlanta had no SRY gene.)

The X Chromosome
- The X chromosome carries hundreds of genes but few, if any, of these have anything to do directly with sex


Survival and Development of Organisms

- There are 4 main means by which living organisms develop and nurture their offspring: Spores, Seeds, Eggs and development in the womb.

Spores:
- A spore is a reproductive body encased within a protective shell
- If bad environmental conditions these spores will exist in suspended animation until the environment becomes suitable for their development
- Spores contain genetic information which are surrounded by a tough cell wall (ex. bacteria)

Seeds:
- A seed contains the plant embryo wrapped in a protective package that contains food
- Seeds bring with them nutrients so as to get a head start on life
- Oranges would be and ex. of a protected seed, while pine cones are examples of a naked (not protected) seed
- Seeds are formed by the ovary of the flower

Eggs:
- An egg is a zygote and some food with some sort of mechanism for protection (ex. a hard shell)
- Some animals fertilize the eggs internally (ex. birds) and others externally (ex. fish)
- Species like the tape worm will lay thousands of eggs at once so as to ensure that some of the eggs will hatch
Marsupial Mammals:
- The offspring are born tiny and immature (ex. kangaroos)
- After emerging from the uterus they crawl into a pouch and attach themselves to a nipple
- When large enough these creatures will leave the pouch and return for milk as long as the mother allows

Placental Mammals:
- Young develop in the uterus or womb (this is most mammals)
- Nutrients from the mother pass along into the embryo, waste from the embryo is also diffused into the mothers blood and passed along to be excreted
- Placental mammals develop less quickly then other types of mammals and require greater long term care
- The mother is required to provide her young with milk and protection as well as teach them about survival

Questions: 1 - 4 pg. 235


Human Conception and Pregnancy

- During intercourse about 150 - 300 million sperm are released, however only a couple of hundred reach the oviducts and egg
- The sperm can exist in the oviduct for up to 5 days, while the egg is capable of surviving for only 48hrs if it is not fertilized
- Within hours of fertilization, tiny hairlike cilia line the oviduct moving the zygote into the uterus
- Around the 4 day, a 16-cell mass enters the uterus where it floats freely for two days, while the cells continue to divide to about100 cells, at this point it implants itself onto the wall of the endometrium and is know called an embryo
- The placenta is created through the joining of embryonic and maternal blood vessels
- Through the placenta nutrients and oxygen diffuse from the mothers blood vessels to the child and waste moves from the child to the mother through the same method
- The placenta after 3 months of pregnancy produces large amounts of estrogen and progesterone so as to ensure that she cannot conceive again until after birth

Fetal Alcohol Syndrome (FAS)
 - The placenta acts as a barrier against large molecules but does allow smaller molecules, like oxygen, through
 - Other molecules though are also able to slip through such as alcohol, drugs, tobacco, etc.
 - When a mother consumes things like alcohol it crosses the placenta and enters the blood of the embryo
- (The effects on an adult (over 19) when drinking the alcohol depresses the functioning of the nervous system, it is also a poison which is broken down in the liver)
 - The effects on the embryo are the same on the child as they are on the mother, the childs nervous system is depressed and the poison remains in the liver
 - Unfortunately the liver is not developed until the last few months of pregnancy, therefore the alcohol exist in the baby for much longer then the mother
 - Alcohol has the potential to kill many different embryonic cells it also can change the genetic information in some cells producing a mutation
- There are many different defects associated with FAS:
 - mental disabilities  - abnormal facial features
 - central nervous system damage
 - behaviourial difficulties - growth deficiencies
 - The severity of FAS depends on the amount of alcohol consumed by the mother and at what stage the alcohol was consumed
 - It is estimated that 60% - 70% of women who are alcoholics give birth to FAS babies
 - A women does not need to be an alcoholic to have a child with FAS, women who have admitted to having a glass a day or less on average have born babies with FAS
 - Alcohol is the leading cause of fetal damage in the country and the leading cause of preventable mental disabilities