Gen Bio pt. 2

Relevant Vocabulary

1. Development- involves formation of sex cells, zygote formation, subsequent stages in one's life span. Development is terminated by death.

2. Haploid (n) condition- When a cell has only half the chromosome number or only one set of chromosomes

3. Diploid (2n) condition- When a cell has the full chromosome number or two sets of chromosomes 4. Totipotent cell- A cell that is capable of differentiating to become any kind of cell

4. Gametogenesis- Stage of development that yields haploid gametes

5. Fertilization- Stage of development that results in a unicellular diploid zygote

6. Cleavage- Stage of development involving a series of mitotic divisions to produce a multicellular blastula from a unicellular zygote

7. Gastrulation- Stage of development involving morphogenetic movements of the cells to produce a gastrula with distinct germ cell layers; in vertebrates, this will result in three layers: the outermost ectoderm; the inner endoderm, and the middle layer, the mesoderm

8. Organogenesis- Stage of development where the different germ layers differentiate into specific organ systems

9. Growth- Stage of development characterized by an increase in size of an individual

10. Monozygotic twins- Also known as identical twins; result from the union of a sperm and egg to form a single zygote that splits up during the first cleavage stage.

2. Dizygotic twins - Also known as fraternal twins; results from the development of two or more separate fertilization events where the resulting zygotes develop almost simultaneously 13. Testis- Where sperms are produced

3. Epididymis- Where sperms are temporarily stored

4. Scrotal sac/scrotum - Supports the testis and epididymis

5. Vas deferens - Where the sperm passes through from the testis before it joins the urethra

6. Urethra - Connected to the urethra and the urinary bladder; serves as passageway of both sperm and urine and terminates in the external urinary meatus of the penis

7. Seminal vesicle - Secretes fluid that forms part of the semen; secretion gives the semen its alkaline characteristic to counteract the acidity of the vaginal tract and therefore protect the sperm; the fluid also contains sugars like fructose

8. Prostate gland - Secretes fluid that also provides alkalinity to the semen; it also contains proteolytic enzymes, citric acid, phosphatases, and lipids

9. Bulbourethral glands- Paired glands that produce clear, viscous secretion known as pre-ejaculate that helps to lubricate the urethra for sperm to pass through, neutralizing traces of acidic urine in the urethra, and helps flush out any residual urine or foreign matter

10. Clitoris- The homologue (equivalent) of the penis in females

11. Vagina- Main entrance to the female reproductive tract; receives the penis during sexual intercourse

12. Cervix- Where the vagina ends; projection of the uterus into the vagina; leads to the uterus

13. Uterus- Also known as the womb; where the embryo develops; with thick muscular walls, blood vessels; and the endometrial lining

0. Ovulation-suppressing methods- Type of contraception that prevents the oocyte to mature

1. Oral contraceptives- Type of contraception taken in by women to prevent them from ovulating 42. Barrier methods- Type of contraception that prevents fertilization

I. phagocytosis - engulfment of organic fragments or big particles, eg. pseudopod formation in Amoeba. II. pinocytosis - uptake of extracellular fluid by a cell using small vesicles derived from the plasma membrane. III. receptor-mediated endocytosis - this relies on membrane receptor recognition of specific solutes which are then taken up by the cell via receptor-coated pits. Cite the different types of animals based on feeding mechanisms: I. substrate-feeders - animals that live in or on their food source. Examples: earthworms that feed through the soil where they live in; caterpillars that eat through the leaves where they live on. II. filter-feeders - include many aquatic animals which draw in water and strain small organisms and food particles present in the medium. Examples: whales and coelenterates III. fluid-feeders - suck fluids containing nutrients from a living host. Examples: mosquitoes, leeches, head lice, aphids IV. IV. bulk-feeders - eat relatively large chunks of food and have adaptations like jaws, teeth, tentacles, claws, pincers, etc. that help in securing the food and tearing it to pieces. Examples: snakes, cats, man

3. Condom- Type of barrier method that is inserted on the male penis to prevent release of sperm into the female reproductive tract

4. Diaphragm- Type of barrier method that blocks the cervix, thereby preventing the passage of the sperm into the uterus

5. Cervical cap- Type of barrier method that covers the cervix and blocks passage of the sperm into the uterus

6. Spermicidal jelly or foam- Type of barrier method that kills the sperm on contact; they are placed inside the vaginal canal

7. Surgical methods- A special type of contraception preventing fertilization that involves surgery 48. Vasectomy-Type of surgical method for men; entails cutting the vas deferens

8. Tubal ligation- Type of surgical method for women; entails cutting the fallopian tubes

9. Implantation-suppressing methods- Type of contraception that prevents the blastocyst from being implanted in the endometrium

10. Intra-uterine devise (IUD)- Type of implantation-suppressing method that physically blocks the blastocyst form implanting into the endometrium

11. Morning-after pill- Type of implantation-suppressing method that blocks the action of hormones that prepare the uterus to receive the embryo

12. Abortion- Type of contraception that involves the deliberate removal of the embryo/fetus before it completes gestation

13. Coitus interruptus- Type of contraception that requires the man to remove the penis before ejaculation

14. Abstinence- Type of contraception where the man and the woman do not engage in sexual intercourse

1. Introduce the concept of calories from food.

A Calorie is a unit of energy that indicates the amount of energy contained in food. It specifically refers to the amount of heat energy required to raise the temperature of 1 kg (2.2 Ib.) of water by 1°C (1.8°F). The greater the number of Calories in a quantity of food, the greater energy it contains (Johnson and Raven, 1996).

2. Identify the nutritional requirements of animals:

3. Carbohydrates - serve as a major energy source for the cells in the body. These are usually obtained from grains, cereals, breads, fruits, and vegetables. On average, carbohydrates contain 4 Calories per gram.

II. Proteins - can also be used as an energy source but the body mainly uses these as building materials for cell structures and as enzymes, hormones, parts of muscles, and bones. Proteins come from dairy products, poultry, fish, meat, and grains. Like carbohydrates, proteins also contain 4 Calories per gram. III. Fats - are used to build cell membranes, steroid hormones, and other cellular structures; also used to insulate nervous tissue, and also serve as an energy source. Fats also contain certain fat-soluble vitamins that are important for good health. Fats are obtained from oils, margarine, butter, fried foods, meat, and processed snack foods. They contain a higher amount of energy per gram than carbohydrates or proteins, about 9 Calories per gram.

IV. Essential Nutrients - include substances that animals can only get from the foods they eat because they could not be synthesized inside the body. These include: A. Essential amino acids – needed for synthesis of proteins and enzymes; among the 20 amino acids, eight could not be synthesized by humans: lysine, tryptophan, threonine, methionine, phenylalanine, leucine, isoleucine and valine. B. Essential fatty acids - used for making special membrane lipids; an example is linoleic acid in humans. C. Vitamins - organic molecules required in small amounts for normal metabolism; examples include fat-soluble Vitamins A, D, E, K, and water-soluble Vitamins B, B2, B3, B12, C.

1. Define gas exchange:

I. Gas exchange is the uptake of molecular oxygen from the environment and the discharge of carbon dioxide to the environment. II. It is often called respiratory exchange or respiration but it should not be confused with cellular respiration. III. Oxygen is needed in tissues for aerobic cellular respiration to occur and extract ATP from food. IV. Carbon dioxide must be released to prevent physiological pH in tissues from being very acidic. In plants however, the carbon dioxide that is released as a by-product of cellular respiration may again be taken up for the process of photosynthesis.

I. liver- secretes bile for emulsifying fats II. gallbladder - stores bile produced by the liver III. pancreas - secretes enzymes that break down all major food molecules; secretes buffers against HCI from the stomach; secretes the hormone insulin for control of glucose metabolism