Chapter 5 and Chapter 6
Which type of stem cell can grow into any other cell type?
totipotent
polar bodies
haploid cells produced during meiosis which have little more DNA and are disintegrated
What happens in meiosis I
homologous chromosomes are separated from one another Division of homologous chromosomes
If a mutation occurs in a gene on chromosome #3, then this mutation could be passes along to offspring if it occurs
in a sex chromosome that undergoes fertilization.
What are the two major stages of the cell cycle
interphase and mitotic phase
xy = ?
male
Gametes are
sex cells
Stem cells can do
1. divide and create new cells for long periods of time 2. Remain undifferentiated in form 3. develop into a variety of specialized cells types
If the process of meiosis proceeds normally, how many chromosomes will each of the 4 resulting daughter cells have within them? (4 chromosomes in
2 each
Which of the following best describes the genetic material a person receives from his or her father?
22 autosomes and an X or Y chromosome
How many chromosomes are in a human gamete?
23
What is the product of meiosis?
4 haploid gamete cells
Human body has how many chromosomes
46
tissue
A group of similar cells that perform the same function.
advantages and disadvantages of sexual reproduction
Adds diversity Slower - must make gametes (egg and sperm) then find mate
A scientist wants to use asexually reproducing vegetables to increase crop yields. He plans to distribute budding potatoes and teach farms how to separate them into new plants. By during this type of propagation, he is creating plants that are all the same genetically. What are potential benefits and risks that could result from this situation?
Benefits - The rate of division is quick (bc they don't have all the organelles) Risks - They all are susceptible to a disease bc they are the same. They can pass on a bad trait.
What is the main difference between binary fission and mitosis?
Binary fission occurs in single-celled organisms only.
Somatic cells are
Body cells
Stem cells can form many kinds of cells. In contrast, most body cells cannot form different types of cells. For example, skin cells only make skin cells, and nerve cells only make nerve cells. Which statement best explains why skin cells will never become nerve cells?
Both types of cells have the same DNA, but each cell uses only part of the DNA message to makes different proteins.
Pluripotent
Can grow into any cell type except totipotent cells Ex. Kidney
Multipotent
Can grow into cells of a closely related origin
What is cytokinesis
Division of cell/cytoplasm
Researchers crossed two types of mice together, type A and type B. In the resulting offspring, half of the DNA comes from type A and half comes from type B. Why?
Each parent contributes one set of chromosomes to each offspring.
What happens in interphase
G1 - Cell does job, growth Synthesis - duplicate DNA G2 - Checkpoint (makes sure they did the steps above)
organs
Groups of tissues that work together to perform specific functions
What phase does the cell live most of its life in
Interphase (90%)
Which of the following statements is true of asexual reproduction?
It produces genetically identical offspring.
Suppose an organism usually has 24 chromosomes in its nucleus. How much genetic material would it have in the cell by the end of interphase?
It would have 48 sister chromatids.
How does the process of mitosis differ from cytokinesis?
Mitosis is the division of the cell's DNA. The process includes prophase, metaphase, anaphase, and telophase. Cytokinesis is the division of the cytoplasm. At the end of telophase, the cell is almost about to break away and become two cells. Cytokinesis divides the cytoplasm causing the cell to break into two cells.
organ system
Organs that carry out similar functions
Which phrase best describes the process of crossing over?
Pairs of homologous chromosomes exchange segments.
Cell differentation
Process by which unspecialized cells develop into their mature forms and function
Gametogenesis
Process of formation of the males and female gametes
List one similarity and one difference between binary fission and mitosis.
Prokaryotic cells bc don't have a nucleus do binary fission and Eukaryotic cells bc do have a nucleus do mitosis. one parent cell is divided into two genetically identical daughter cells.
The reproduction of cells in your body does 3 things which are
Replacement of lost or damaged cells Growth of the cell Asexual
Two pea plants were both grown from green peas. When these plants were crossed, their offspring produced green, yellow, and white peas. What accounts for the differences between parents and offspring?
Sexual reproduction has produced new combinations of alleles.
At fertilization, what happens to the sex cells?
Their nuclei fuse to form one nucleus. (Two cells become one cell during the process of fertilization. Remember, once fertilization has occurred, the diploid cell that was produced undergoes many, many mitotic divisions to form the body cells of a baby.)
Suppose a gene that codes for flower color is linked with a gene that codes for leaf shape. Which statement is true of this pair of genes?
They are close together on the same chromosome. (This means they tend to be inherited together and they are less likely to be separated during recombination.)
What happens to sister chromatids in meiosis II?
They are divided.
Which of the following statements is true of homologous chromosomes?
They contain the same genes but the alleles for each trait may not be the same
Why do prokaryotes divide faster?
They don't have spindle fibers + less DNA. Still make tow daughter cells that are genetically identical
Describe how uncontrollable cell division is dangerous in organisms.
Uncontrollable cell division is dangerous because it can form cancer. The new cells that are created don't do their jobs. They can also put pressure on vital organs. More cells means more energy and resource than might be available. Improper allocation of energy and nutrients to damaged cells could mean that properly working cells could be deprived of nutrients or energy, which could impair the ability of normal cells and the human body to function.
During which phase of mitosis do sister chromatids separate from each other?
anaphase
What is the term for the programmed death of cells?
apoptosis
Vegetative reproduction, budding, and fragmentation are examples of
asexual mitotic reproduction.
Binary fission
asexual reproduction of a single celled organism into two roughly equal parts
cells
basic unit of life, perform all functions of life
The most common form of reproduction among prokaryotes is
binary fission.
Totipotent
can grow into any other type of cell type Only fertilized egg and cells Produced by first divisions of embryo are totipotent
Stem cells are important to multicellular organisms because of their
capacity to differentiate.
Substances known to produce or promote cancer are called
carcinogens.
During the gap 1 (G1) stage of the cell cycle, a cell
carries out its normal functions.
Autosomes
chromosomes that contain genes for characteristics not directly related to the sex of the organism
Sex chromosomes
chromosomes that directly control development of sexual characteristics
external factor
come from outside cell bind to receptors trigger internal factors affecting cell cycle 1. cell to cell contact - cell touches other cells, it stops dividing 2. Cells release chemical signals telling each other cells grow
Which of the following statements is true of cytokinesis?
completes the cell cycle
diploid
contains 2 sets of homologous chromosomes
The processes of mitosis and cytokinesis produce two identical
daughter cells.
What happens in meiosis I?
division of homologous chromosomes
What is mitosis
division of the Nucleus/DNA
Which of the following phrases best describes cytokinesis?
division of the cytoplasm
kinase
enzyme transfer phosphate group form one molecule to a specific target molecule
xx = ?
female
Starfish that reproduce by splitting into pieces are reproducing by
fragmentation.
Which phrase best describes an organ system?
group of organs that work together
cyclins
group of proteins made and destroyed at certain points in cell cycle
Proteins that bind to receptors in the cell membrane and stimulate cell division are called
growth factors.
After being scraped or cut, the skin is able to heal. What biological process best accounts for the replacement of skin cells?
mitosis
In which stage of the cell cycle do the nucleus and its contents divide?
mitosis
The process of organizing and condensing DNA into its compact form takes place at the start of
mitosis.
Karyotype
picture of your chromosomes
apoptosis
programmed cell death occurs when internal and external signals activate genes telling cell to produce self-destructive enzymes
During what stage of meiosis does crossing over occur?
prophase I of meiosis I
Ex. of a multicellular organism the reproduces asexually
sea stars and some plants
Haploid
single set of chromosomes
What happens in meiosis II
sister chromatids are separated but the resulting cells are haploid rather than diploid Division of sister chromatids
A kidney cell is an example of which type of cell?
somatic cell
Gametogenesis is the term for
the production of gametes.
Which of the following limits the maximum size of a cell?
the ratio of cell surface area to volume (Remember that a high SA to Vol Ratio makes diffusion more efficient.)
Cell cycle
the regular pattern of growth, DNA duplication, and cell division that occurs in eukaryotic cells
Which phrase best describes cancer?
uncontrolled cell growth
Stem cells
undifferentitated biological cells that can differentiate into specialized cells and can divide through mitosis to produce more stem cells