Unit 4: Embryology and Cell Reproduction Methods

What 3 things happen in Prophase?

-Chromosomes become more coiled and can be viewed under a light microscope. -Each duplicated chromosome is seen as a pair of sister chromatids joined by the duplicated but unseparated centromere. -The nucleolus disappears during prophase.

Where are diploid cells found?

A diploid chromosome set occurs in most eukaryotes in somatic cells - that is, non-sex cells. These cells contain the entire set of genetic material, or chromosomes, of the organism, or double the haploid chromosome set. Thus, the entire gene set of an organism is located in every cell of that organism.

What is the difference between the following form of DNA? -Sister Chromatids

A sister chromatid refers to the identical copies (chromatids) formed by the DNA replication of a chromosome, with both copies joined together by a common centromere.

What is the difference in the following forms of stem cells? -Multipotent

Adult stem cells that are limited to replacing cells in the tissues in which they are found.

Which phase has cytokinesis?

Anaphase

What is the difference in the following forms of stem cells? -Pluripotent

Can develop into any of the body's cell types (somatic cells, not gametes).

What is the significance of the mitotic phase of the cell cycle?

Cell division occurs during M phase, which consists of nuclear division (mitosis) followed by cytoplasmic division (cytokinesis). The DNA is replicated in the preceding S phase; the two copies of each replicated chromosome (called sister chromatids) remain glued together by cohesins.

How does crossing over contribute to genetic variation? (tetrad)

Crossing over, or recombination, is the exchange of chromosome segments between nonsister chromatids in meiosis. Crossing over creates new combinations of genes in the gametes that are not found in either parent, contributing to genetic diversity.

What does it mean when a cell is 2N?

Diploid describes a cell that contain two copies of each chromosome. Nearly all the cells in the human body carry two homologous, or similar, copies of each chromosome. The total number of chromosomes in diploid cells is described as 2n, which is twice the number of chromosomes in a haploid cell (n).

Describe Interphase.

During interphase, the cell copies its DNA in preparation for mitosis. Interphase is the 'daily living' or metabolic phase of the cell, in which the cell obtains nutrients and metabolizes them, grows, reads its DNA, and conducts other "normal" cell functions. This phase was formerly called the resting phase.

Compare and Contrast: Diploid Cells vs. Haploid Cells.

Haploid = Single (Gametes) Diploid = Double (Body Cells)

Where are haploid cells found?

Haploid cells are found in various algae, various male bees, wasps and ants. Haploid cells should not be confused with monoploid cells as the monoploid number refers to the number of unique chromosomes in one biological cell.

What is the difference between the following form of DNA? -Homologous Pairs of Chromosomes

Homologous chromosomes are made up of chromosome pairs of approximately the same length, centromere position, and staining pattern, for genes with the same corresponding loci.

Compare the number of chromosomes in human gametes to the number of chromosomes in other cells in the body.

In humans, n = 23. Gametes contain half the chromosomes contained in normal diploid cells of the body, which are also known as somatic cells. Haploid gametesare produced during meiosis, which is a type of cell division that reduces the number of chromosomes in a parent diploid cell by half.

Include the stages and what occurs in each

Interphase is composed of G1 phase (cell growth), followed by S phase (DNA synthesis), followed by G2 phase (cell growth). At the end of interphase comes the mitotic phase, which is made up of mitosis and cytokinesis and leads to the formation of two daughter cells.

Why is Interphase not a part of Mitosis?

Interphase is technically not part of mitosis, but it is important because it is discussed as part of the cell cycle and precedes the process of mitosis. In interphase, the cell is in preparation for nuclear division. It is also the beginning stage, where DNA is synthised and proteins are made.

Which phase do they meet in the middle?

Metaphase

Compare and Contrast: Mitosis vs. Meiosis (at least 3 ways in each column)

Mitosis -Exact copy of parent. -Asexual Reproduction. -More efficient/Quick. Meiosis -Has tetrads. -Mixes genes of both parents. -Sexual Reproduction.

True or False: Mitosis only occurs in prokaryotes.

Mitosis is the process in cell division by which the nucleus of the cell divides (in a multiple phase), giving rise to two identical daughter cells. Mitosis happens in all eukaryotic cells (plants, animals, and fungi). It is the process of cell renewal and growth in a plant, animal or fungus.

Are unicellular organisms only able to reproduce asexually? Think about prokaryotic and eukaryotic cells. Explain.

Only prokaryotes (the archaea and the bacteria) reproduce asexually through binary fission. Eukaryotes (such as protists and unicellular fungi) may reproduce in a functionally similar manner by mitosis; most of these are also capable of sexual reproduction. Many Asexual cells normally die off.

Compare and Contrast: Mitosis in Plant Cells vs. Animal Cells?

Plant and animal cells both undergo mitotic cell divisions. Their main difference is how they form the daughter cellsduring cytokinesis. During that stage, animal cells form furrow or cleavage that gives way to formation of daughter cells. Due to the existence of the rigid cell wall, plant cells don't form furrows.

What is the difference in the following forms of stem cells? -Embryonic

Pluripotent stem cells that are more versatile than adult stem cells. They are capable of becoming any cell in the body.

What is the difference between the following form of DNA? -Chromatin

The function of chromatin is to efficiently package DNA into a small volume to fit into the nucleus of a cell and protect the DNA structure and sequence. Packaging DNA into chromatin allows for mitosis and meiosis, prevents chromosome breakage and controls gene expression and DNA replication.

Compare and Contrast: Sexual vs. Asexual Reproduction.

The main difference between sexual and asexual reproduction would be.. that Sexual reproduction just means combining genetic material from two parents. Asexual reproduction produces offspring genetically identical to the one parent.

2 ways mitosis is different in plants and animals?

The most important and observable difference in the plant animal cells mitosis is the cytokinesis. In plants a new cell plate is formed between the daughter cells for the future cell wall, while in animal cells the cell membrane constricts to separates the parent cell into daughter cells.

Compare and Contrast: Benign Tumors and Malignant Tumors?

There are two main classifications of tumors. One is known as benign and the other as malignant. A benign tumor is a tumor that does not invade its surrounding tissue or spread around the body. A malignant tumor is a tumor that may invade its surrounding tissue or spread around the body.

What is the difference between the following form of DNA? -Chromosomes

a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.

What is the difference in the following forms of stem cells? -Totipotent

the cell that is able to do everything, to develop into any type of cell in the body. This only occurs in cells that make up embryonic membranes, placenta, and fertilized egg.

What is a stem cell and why is it important?

unspecialized cells from which differentiated cells develop, found in the early embryo and in many places in the adult body. Stem cells are important for living organisms for many reasons. ... In some adult tissues, such as bone marrow, muscle, and brain, discrete populations of adult stemcells generate replacements for cells that are lost through normal wear and tear, injury, or disease.