Human Biology BIOL-105 Lab Manual 2024-2025 PDF

Human Biology BIOL-105 Laboratory Manual Laboratory 3 LABORATORY 3 CELL CYCLE, MITOSIS, MEIOSIS AND GAMETOGENESIS Cells are produced from pre-existing cells by cell divi...

Human Biology BIOL-105 Laboratory Manual Laboratory 3 LABORATORY 3 CELL CYCLE, MITOSIS, MEIOSIS AND GAMETOGENESIS Cells are produced from pre-existing cells by cell division. Cell divisions involves two types of nuclear divisions: mitosis or meiosis which are followed by cytoplasmic division (cytokinesis). 3.1 Cell Cycle: It is a cycle of stages that new cells pass through to allow them to divide and produce new cells. The Cell Cycle consists of: 1. Interphase: (non dividing period). It consists of: G1, S, and G2. 2. Cell division: Mitosis or M-phase (Nuclear division). Cytokinesis (cytoplasmic division). Two daughter cells Figure 3.1 The Cell Cycle Biology Unit, Imam Abdulrahman Bin Faisal University 48 Human Biology BIOL-105 Laboratory Manual 3.2. Chromosomes: Before cell division, DNA molecules replicate themselves. At the beginning of division, DNA appear as duplicated chromosomes consisting of two sister chromatids held together at centromere. During cell division, the two sister chromatids separate into two unduplicated chromosomes. Each human somatic cell has 46 chromosomes. Two sister chromatids Centromere Replication Division One One Two unduplicated chromosome duplicated chromosome unduplicated chromosomes Figure 3.2 Chromosomes Biology Unit, Imam Abdulrahman Bin Faisal University 49 Human Biology BIOL-105 Laboratory Manual 3.3 Karyotype The image of all pairs of homologous chromosomes (homologues) of an organism arranged depending on their size (from the largest to smallest), centromere position, gene locations and banding pattern Materials: Image of human male and human female karyotype (Fig. 3.3). Methods: Observe the images of human male and female karyotypes. sister chromatids centromere Two homologous chromosomes Sex chromosomes in male Human male Karyotype XY Sex chromosomes in female X X Human female Karyotype Figure 3.3. Human Karyotype Biology Unit, Imam Abdulrahman Bin Faisal University 50 Human Biology BIOL-105 Laboratory Manual Nuclear envelope fragments Mitotic spindle Centrioles Chromatin condenses Duplicated chromosomes to chromosomes 2. Metaphase 1. Prophase Two daughter nuclei Unduplicated chromosomes Cleavage furrow 3. Anaphase 4. Telophase Figure 3.4. Stages of Mitosis Biology Unit, Imam Abdulrahman Bin Faisal University 52 Human Biology BIOL-105 Laboratory Manual Animal cell model Plant cell Interphase: DNA is in the form of chromatin. Chromosomes are not visible. Nuclear envelope and nucleolus are present. Prophase: Chromosomes condense Centrioles migrate to opposite poles. Nuclear envelope disappears. Spindle fibers form. Early Late Metaphase: All duplicated chromosomes are aligned at the spindle equator. Figure 3.5. Stages of the cell cycle (Interphase, Prophase, and Metaphase) Biology Unit, Imam Abdulrahman Bin Faisal University 53 Human Biology BIOL-105 Laboratory Manual Mitosis model: https://www.youtube.com/watch?v=TsP9llFT4ZQ Animal cell model Plant cell Anaphase: Sister chromatids separate and move to the opposite spindle poles. Telophase: Chromosomes (unduplicated) decondense, nuclear envelope reforms, spindles disappear. Daughter cells Late telophase and cytokinesis Cleavage furrow Cell plate Figure 3.6. Stages of the cell cycle (Anaphase, Telophase and Cytokinesis) Biology Unit, Imam Abdulrahman Bin Faisal University 54 Human Biology BIOL-105 Laboratory Manual Examine the microscopic slides and models. Draw the different stages of the cell cycle Interphase Prophase Metaphase Anaphase Telophase Cytokinesis and two daughter cells Biology Unit, Imam Abdulrahman Bin Faisal University 55 Human Biology BIOL-105 Laboratory Manual Activity 3.1 Identify the following stages of the cell life cycle? Name: ………………..…….. Description: ………………..………….…. Chromosomes (unduplicated) decondense, ………………..…………….. nuclear envelope reforms, spindles disappear. Name: ……………………….. Description ………………..………….…… *DNA is in the form of chromatin. ………………..………….…… *Chromosomes are not visible. *Nuclear envelope present. Name: ………………………. Description: ………………..………….….. All duplicated chromosomes are ………………..……………… aligned at the spindle equator. Name: ………………………. Description: ………………..………….….. Sister chromatids separate and ………………..……………… move to the opposite spindle poles. Biology Unit, Imam Abdulrahman Bin Faisal University 56 Human Biology BIOL-105 Laboratory Manual MEIOSIS I Interphase MEIOSIS II Prophase I Similar to mitosis Chromosomes condense. Centrioles move, spindle forms. Nuclear envelope breaks. Homologous chromosomes pair Prophase II up during synapsis. Crossing over occurs. Metaphase I Homologous chromosome pairs align at the metaphase plate. Metaphase II Anaphase I Homologous chromosome separate. Anaphase II Telophase I Chromosome reach the poles. Spindles disappear. Nuclear envelope Telophase II reforms. Interkinesis Cytokinesis completed Two haploid daughter cells result. Cytokinesis Four haploid daughter germ cells result Figure 3.7 Different Stages of Meiosis Biology Unit, Imam Abdulrahman Bin Faisal University 58 Human Biology BIOL-105 Laboratory Manual Prophase I Prophase I: crossing over Meiosis I Metaphase I Anaphase I Telophase I Telophase I & cytokinesis Meiosis II Four new cells are formed Figure 3.7 Different Stages of Meiosis (Models of animal cells) Biology Unit, Imam Abdulrahman Bin Faisal University 59 Human Biology BIOL-105 Laboratory Manual Spermatogenesis: Production of sperm in male testes. Spermatogonium Duplication (2n) Of Interphase Epididymis Testis Primary spermatocyte (2n) Coiled Meiosis I seminiferous Secondary spermatocyte tubules Meiosis II (n) Spermatids (n) Mature sperm cells Vas deferens (n) Human testis Spermatogenesis Spermatid Seminiferous tubule Mature sperm Tail Midpiece Head Interstitial cells sperm T. S. of testis showing spermatogenesis in seminiferous tubules Human sperm Figure 3.8. Human Testis, Sperm and Spermatogenesis Biology Unit, Imam Abdulrahman Bin Faisal University 62 Human Biology BIOL-105 Laboratory Manual Oogenesis: Production of oocytes in female ovaries. Oogenesis Primary Oogonium oocyte (2n) Meiosis I Second polar body (n) Secondary Primary oocyte oocyte (n) Meiosis II Meiosis II is completed after entry of sperm Secondary oocyte + Second polar (fertilization) body (n) polar body Fertilization Egg (n) Ovum + polar body Sperm nucleus (n) Fusion of sperm Oogenesis nucleus and Zygote egg nucleus (2n) Oogenesis & Fertilization Secondary oocyte Ovaries Oviduct Secondary oocyte Follicles Mature follicle Corprus luteum Uterus T. S. of ovary showing mature follicle with secondary oocyte Female reproductive system Figure 3.9. Oogenesis & Fertilization Biology Unit, Imam Abdulrahman Bin Faisal University 63 Human Biology BIOL-105 Laboratory Manual Activity 3.2 Answer the following questions: 1. Name the phase of mitosis during which separation of sister chromatids occurs. ----------------------------------------------------------------------------------------------- 2. Where in humans would you expect to find meiosis taking place? -------------------------------------------------------------------------------------------- 3. The term cytokinesis refers to what? the division of the cytoplasm of a cell -------------------------------------------------------------------------------------------- 4. If there are 16 pairs of homologues at the start of spermatogenesis, how many chromosomes are there in a sperm? 16 chromosomes ----------------------------------------------------------------------------------------------- 5. Homologous chromosomes lined up at the spindle equator at which stage? Metaphase I of Meiosis ----------------------------------------------------------------------------------------------- 6. If homologous chromosomes are separating, what phase is this? ---------------------------------------------------------------------------------------------- Biology Unit, Imam Abdulrahman Bin Faisal University 65 Human Biology BIOL-105 Laboratory Manual LABORATORY 4 GENETICS Genetics is the study of DNA and genes and their transmission from one generation to the next. A gene is the unit of heredity. Genes encode for specific proteins, and each gene has a specific location on a particular chromosome. Alleles are alternative versions of a gene. Most traits are controlled by two alleles in one individual. That said, not all alleles we inherit are shown. Some alleles, the dominant ones, mask the expression of the recessive alleles. Dominant alleles are designated by uppercase letters (A for example) while recessive alleles are designated by lowercase letters (a for example). Homozygous: having identical alleles of a particular gene (AA/DD/aa/dd). Heterozygous: having different alleles of a particular gene (Aa/Dd). Genotype: the genetic makeup of an individual (AA, Aa, Dd, dd, …) Phenotype: the observable physical and functional traits of an organism such as attached earlobe, brown eyes, purple flowers,… Biology Unit, Imam Abdulrahman Bin Faisal University 66 Human Biology BIOL-105 Laboratory Manual 4.2. Mendelian Genetics of Corn Gregor Mendel, known as the father of genetics, conducted all his experiments on the pea plant and founded the laws of Mendelian inheritance. In our lab though, we will be illustrating some of these laws using corn ears (cob) rather than pea plants. The characters we will be examining today are kernel (seed) color and kernel shape. They are summarized below and example images are provided for further clarification. Dominant allele and Recessive allele and Character phenotype phenotype Kernel color A: purple-colored kernels a: yellow-colored kernels Kernel shape B: smooth kernels b: wrinkled kernels a. b. c. d. Fig 4.2. a. Monohybrid cross of kernel shape (smooth and wrinkled). b. Monohybrid cross of kernel color (purple and yellow). c. Dihybrid cross. d. Examples of kernel color and shape. Biology Unit, Imam Abdulrahman Bin Faisal University 68 Human Biology BIOL-105 Laboratory Manual Activity 4.1 Genetics Problem: A corn cross was made between a plant heterozygous for purple smooth kernels and a plant with yellow wrinkled kernels. Draw a Punnett square for this cross to predict genotypic and phenotypic ratios of their offspring. Biology Unit, Imam Abdulrahman Bin Faisal University 71 Human Biology BIOL-105 Laboratory Manual 4.3. Human Genetics Human genetic traits can be used to illustrate several inheritance patterns. Examples include complete dominance, codominance, and sex-linkage. In some instances, a single gene determines some traits like tongue rolling and dimples (monogenic). Other traits, like skin color and height, are more complex and result from the action of many genes (polygenic). The following table shows the inheritance pattern of some monogenic human characteristics. All traits being examined are autosomal traits, meaning they are determined by alleles on autosomal chromosomes and not sex chromosomes and they are controlled by two alleles. Biology Unit, Imam Abdulrahman Bin Faisal University 72 Human Biology BIOL-105 Laboratory Manual For each of the traits listed in the following table, fill out your phenotype and your possible genotype(s). Remember, if you show a dominant trait, you may be homozygous or heterozygous for that trait. Table 1. Student Traits Trait Phenotype Genotype(s) Earlobes (E, e) Tongue rolling (T, t) Widow’s Peak (W, w) Dimples (D, d) Interlocking fingers (L,l) Double-jointed thumb (H, h) Biology Unit, Imam Abdulrahman Bin Faisal University 73 Human Biology BIOL-105 Laboratory Manual The tables below summarize the different possible genotypes and phenotypes for blood groups and Rh factor. Human Blood Groups Genotype Phenotype Antigen present on RBCs IAIA A A IAi A A IBIB B B IBi B B IAIB AB A&B ii O None Human Rh factor Genotype Phenotype Antigen present on RBCs DD Rh+ Rh Dd Rh+ Rh dd Rh- None Biology Unit, Imam Abdulrahman Bin Faisal University 75 Human Biology BIOL-105 Laboratory Manual 8. Fill in the column for your sample in the Blood Groups Data Table (found in Activity 5.2), answering with yes or no as to whether agglutination occurred with each antiserum. 9. Exchange blood typing slides with other groups and collect data for the remaining 3samples. 10. Thoroughly rinse the blood typing slide and set aside to dry. Fig 4.3: Demonstration of blood type readings. *NOTE: D is anti-Rh Biology Unit, Imam Abdulrahman Bin Faisal University 77 Human Biology BIOL-105 Laboratory Manual Activity 4.2 Blood Groups Data Table Possible Anti-A Anti-B Anti-Rh Blood type Genotypes Sample 1 Sample 2 Sample 3 Sample 4 Blood Typing Problems 1. If a child has type AB blood and the father has type B blood, what are the possible genotypes of the mother? _______________________________________ 2. If a mother and father both have type AB blood, they cannot be the parents of a child who has what blood type? __________________________ 3. What blood types are possible among the children of parents IAi × IBi? (Hint: Draw a Punnett square using the possible gametes for each parent.) 4. A married couple both with type A blood have a child with blood type O. What is the genotype of each person? (use the correct alleles: I A, IB, i) Father: ___________________ Mother: ___________________ Child: ___________________ Biology Unit, Imam Abdulrahman Bin Faisal University 78 Human Biology BIOL-105 Laboratory Manual Activity 4.3 Genetic lab review 1. For the following crosses, write: P B A F1 F2 Type of the cross (monohybrid or Type of the cross (monohybrid or dihybrid):________ dihybrid):________ Genotype of A kernels: ________ Genotype of B kernel is ________ Phenotypic ratio in F2: ________ Genotypic ratio in F2 ________ 2. If the following is the result of blood type test, what is the examined blood type? 79