Ch 8: The Cellular Basis of Reproduction and Inhertitance

Describe the stages of cell division.

(1) Interphase: when mitosis is going to happen, but not yet (2) Prophase: when mitosos really starts, chromasomes begins to wrap around histones, nuclear envelope breaks down (3) Metaphase: sister chromatids line up (4) Anaphase: chromatids pull apart, each cell is getting sister chromatids as they move twowad the poles that are on opposite sides of the cell (5) Telaphase: see clevage furrow, pinching together in the middle (6) Cytokinesis: division into two daughter cells is completed

Explain how anchorage, cell density, and chemical growth factors control cell division.

A growth factor is a protein made by certain body cells that stimulates cell division. Cells are dependent on anchorage (contact with a solid surface) to divide. Density plays an important factor for once the cell has formed a complete layer, it stops dividing. Cells are unable to divide without if an essential nutrient is left out of the culture.

explain how and why karyotyping is preformed

A karyotype is a photographic inventory of an individual's chromosome Chromosomes lined up. Shows completeness and gender picture of all the sets of chromosomes

period in the cell cycle which a cell is not dividing

Anaphase

Explain how daughter prokaryotic chromosomes are separated from each other during binary fission.

As the chromosome is duplicating, the two daughter bacteria copies go to opposite ends of the cell, while the cell pinches itself off, when chromosome duplication is complete, the cell will be half it's original size, the plasma membrane grows inward and more cell wall is made, pinching off into two identical daughter cells.

Explain how cancerous cells are different from healthy cells.

Cancerous cells divide uncontrollably, often with the absence of growth factors. They spread to other tissues, through the circulatory system. Growth without being inhibited by other cells.

cyclically operating set of molecules in the cell that triggers and coordinates key event in the cell cycle

Cell Cycle Control System

centralized region joining two sister cromatids

Centromere

explain how independent orientation of chromosomes at metaphase 1, random fertilization, and crossing over during prophase 1 of meiosis contribute to genetic variation in sexually reproducing organisms

Crossing Over - genes alleles are swapped, allowing for genetic diversity of the gametes Independent orientation of chromosomes— equal probability of the maternal or paternal chromosome facing a given pole

reciprocal exchange of genetic material between non sister chromatids during the synopsis of meiosis 1

Crossingover

a haploid cell such as an egg or sperm. gametes unite during sexual reproduction to produce a diploid zygote

Gamete

Compare the parent-offspring relationship asexual and sexual reproduction.

In asexual reproduction, the parent's offspring are replicas with identical genes, without the joining of egg and sperm. For example, some species of starfish reproduce asexually from their broken off pieces. In sexual reproduction however, it requires the fertilization of the egg by sperm. Offspring typically resemble their parents more than any other non-related member of that specie, but they are not identical. Each offspring inherit their own combination of the two parent genes.

Compare cytokinesis in animal and plant cells.

In plants, the division of the cytoplasm into two cells, typically begins during telophase, instead of during cytokinesis and results in two daughter cells with their own cell wall. In animal cells, cytokinesis occurs by a process known as cleavage (the first sign is the cleavege furrow).

phase of the cell cycle which includes mitosis and cytokinesis

Interphase

List the events of mitosis and describe the events characteristic of each phase.

Interphase: Before cell division takes place Prophase: when cell division really begins Metaphase: sister chromatids line up to divide Anaphase: chromatids devide and move toward poles Telophase: cell begins to pinch in two Cytokinesis:two identicle daughter cells are formed

third subphase of mitosis

Metaphase

define nondisjunction, explain how it can occur, and describe what can result

Nondisjunction is when chromosomes divide incorrectly and the daughter cell(s) end with an abnormal chromosome number.

Compare the structure or prokaryotic and eukaryotic chromosomes.

Prokaryotic chromosomes lack a membrane-enclosed nucleus and other membrane-enclosed organelles. Found only in types of Bacteria and Archaea Chromosomes that are eukaryotic have a membrane-enclosef nucleus and other membrane-enclosed organelles. All organisms accept bacteria and archaea are made of eukaryotic cells.

second subphase of mitosis

Prometaphase

Describe the functions of mitosis.

Provides for growth, cell replacement, and asexual reproduction.

Explain why cell division is essential for prokaryotic and eukaryotic life.

Some cell division results in a whole new organism. Prokaryotic organisms like the yeast cell reproduce by dividing in half, making the offspring genetic replicas. Cell division enables sexually reproducing organisms to develop from a single cell. Cell division also repairs, and replaces cells that die. Within your body, millions of cells must divide every second to replace damaged or lost cells.

the requirement that to divide, a cell must be attached to the substratum

anchorage dependence

a chromosome that is not directly involved in determining sex

autosome

Explain why sexual reproduction requires meiosis.

because that is sex and how babies are formed

mass of abnormal cells that remains at the site of the origin

benign tumor

reproduction of cells

cell division

material present in the cytoplasm of all eukaryotic cells, important during cell division,microtubule organizing center

centrosome

threadlike gene carrying structure found in the neucleous

chromosomes

describe the main types of chromosomal changes

deletion duplication inversion

phenomenon observed in normal animal cells that causes them to stop dividing

density-dependent inhibition

explain how new species form from errors in cell division

different genetics form different plants

aberration in chromosome structure resulting from an error in meiosis or mutagens:duplication of a portion of a chromosome resulting from fusion with a fragment from a homologous chromosome

duplication

describe causes and symptoms of Down syndrome

extra copy of 21

union of haploid gametes to produce a diploid zygote

fertilization

protein that must be present in extracellular environment

growth factor

Explain how chromosomes are paired.

identical genes, length, and position

aberration in chromosome structure resulting from an error in meiosis or mutagens: reattachment of a chromosomal fragment to the chromosome from with the fragment oriented

inversion

describe the consequences of abnormal numbers of sex chromosomes

klinefelter syndrome (male) turner syndrome (female)

sequence of life stages leading from the adults of one generation to the adults of the next

life cycle

cancers of the tissue that form white blood cells

lymphomas

mass of abnormal cells caused by the uncontrolled growth of a transformed cells

maligaint tumor

type of cell division by which prokaryotes reproduce

meiosis

List the phases of meiosis I and II and describe the events characteristic of each phase.

meiosis 1= prophase 1-chromosomes split and coil and cross over spindle is formed metaphase 1-lined up at central plate anaphase 1-split apart telophase 1 and cytokinesis- cleavage furrow formed and cells split apart meiosis 2= prophase 2- same but both cells metaphase 2- same but both cells anaphase 2- same but both cells telophase 2 and cytokinesis- haploid daughter cells formed

spread of cancer cells to locations distant from their original site

metastasis

process of nuclear division

mitosis

Compare mitosis and meiosis noting similarities and differences.

mitosis is skin cells meiosis is sex cells

assemblage of microtubules and associated proteins that is involved in the movements of chromosomes during mitosis

mitotic spindle

any cell in a multicellular organism except sperm and egg cell

somatic cell

Distinguish between somatic cells and haploid cells.

somatic cell is a cell in the human body/has 46 chromosomes gametes are sex cells haploid single chromosome set, one member of each homologous pair (n) (n=23) diploid cells are cells with two homologous sets of chromosomes (2n) (2n=46)