Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Cell Growth
and division
| Question | Answer |
|---|---|
| The ______ a cell becomes, the more demands the cells places on its ___. | larger; DNA |
| What is less efficient in a larger cell? | moving nutrients and waste materials across the cell membrane |
| Why is a cell's size limited? | volume increases faster than surface area, and homeostasis is disrupted |
| What happens before cell division happens? | the cell replicates all of its DNA |
| Why does cell division work? | cell division solves the problem of increasing size by reducing cell volume; it results in an increase in the ratio of surface area to volume |
| Is cell division mitosis or meiosis? | mitosis |
| What is asexual reproduction? | the production of a genetically identical offspring from a single parent |
| What is sexual reproduction? | involves the fusion of two separate parent cells - zygote; offspring produced inherit some of their genetic information from each parent |
| What is a prokaryote? | unicellular organisms that lack nuclei |
| Where are DNA molecules found? | in the cytoplasm along with most of the other contents of the cell |
| Most prokaryotes contain a ________, circular ___ chromosome that contains all, or nearly all, of the cell's genetic information. | singular; DNA |
| Why do eukaryotic cells contain multiple chromosomes? | eukaryotic cells generally have much more DNA than prokaryotes have |
| What is chromatin? | a substance found in eukaryotic chromosomes that consists of DNA tightly coiled around histones |
| The ______ is filled with a loose tangle of chromatin. | nucleus |
| What is chromatin made up of? | DNA and proteins |
| Together, what does DNA that tightly coils around histones make? | bead-like structures called nucleosomes |
| What nucleosomes pack together to form? | thick fibers, which condense even further during cell division |
| When cell division begins the arrangement of DNA changes how? | it changes from chromatin to chromosomes |
| What 2 identical parts do chromosomes consist of? | chromatids |
| What is the point at which chromatids are joined? | centromere |
| What are the four phases that make up the eukaryotic cell cycle? | G1(cell growth), S(DNA replication), G2(preparation for mitosis), and M(mitosis/cytokinesis) |
| What happens during cell interphase? | the cell interphase is the longest part of the cell cycle; cells double in size; organelles double in #, and DNA copies itself |
| Interphase is divided into what three parts? | G1, S, and G2 |
| What happens during the G1 phase? | cells increase in size and synthesize new proteins and organelles |
| What happens during the S phase? | new DNA are synthesized when the chromosomes are replicated; the cell at the end of the S phase contains twice as much DNA as it did at the beginning |
| What happens during the G2 phase? | many of the organelles and molecules required for cell division are produced |
| What happens during the M phase? | two daughter cells are produced; follows the interphase |
| How many stages does cell division occur in? | two main stages |
| What is the first stage of cell division? | the division of the cell nucleus, mitosis |
| What is the second stage of cell division? | the division of cytoplasm, cytokinesis |
| What is mitosis? | the division of the cell nucleus in which the chromosomes divide into 2 identical sets |
| What happens in the beginning of the prophase? | the genetic material inside the nucleus condenses and the duplicated chromosomes become visible |
| What happens outside the nucleus during prophase? | a spindle starts to form |
| Where can the duplicated strands of the DNA molecule be seen? | attached along their length at an area called the centromere |
| What are the DNA strands in duplicated chromosomes referred to as? | chromatids |
| What is a spindle? | a fanlike system of microtubules that will help to separate the duplicated chromosomes |
| Where do spindle fibers extend from? | the centrosome |
| Where are centrioles located? | in the centrosome |
| What happens as prophase ends? | the chromosomes coil tighter, the nucleolus 'disappears', and the nuclear envelope breaks down |
| What do chromosomes do in the beginning of metaphase? | line up in the middle of the cell, and the centromeres line up across the center of each cell |
| What do spindle fibers do during the metaphase? | connect the centromere of each chromosome to the two poles of the spindle |
| What happens to centromere during anaphase? | it divides, allowing chromatids to separate and move toward centrioles |
| What happens to the chromosomes during anaphase? | they separate and move along the spindle fibers to opposite ends of the cell |
| What happens to centrioles and spindle fibers during telophase? | the disappear |
| What happens to chromatids during telophase? | they unwind and elongate |
| What forms around each mass of chromatin during telophase? | nuclear membrane |
| What happens to chromosomes near the end of telophase? | they begin to spread out into a tangle of chromatin and a nuclear envelope reforms around each cluster of chromosomes |
| What happens to the spindle at the end of telophase? | it begins to break apart and a nucleus becomes visible in each daughter nucleus |
| What does cytokinesis do? | completes the process of cell division - it split one cell into two |
| What is the cell cycle controlled by? | cyclins |
| What are cyclins? | regulatory proteins both inside and outside the cell |
| What cells do not respond to the signals that regulate the growth of most cells? | cancer cells; this causes the cells to divide uncontrollably |
| What happens to cells during the development of an organism? | they differentiate into many types of cells |
| What are stem cells? | the unspecialized cells from which differentiated cells develop |
| What is a totipotent cell? | a cell that is able to do everything, to develop into any type of cell in the body |
| What cells are truly totipotent? | the fertilized egg and the cells produce by the first few cell divisions of embryonic development |
| What is a blastocyst? | a hollow ball of cells with a cluster of cells inside known as the inner cell mass |
| What do the outer cells of blastocysts form? | tissue that attach the embryo to its mother |
| What do the inner cell masses of blastocysts become? | the embryo |
| What is a pluripotent cell? | a cell that can develop into most, but not all, of the body's cell types |
| What is a multipotent cell? | an adult cell that can develop into many types of differentiated cells |
| What is cytokinesis? | the division of cytoplasm |
| In which phase is DNA made? | the "S" phase |
| What is apoptosis? | the death of cells which occurs as a normal and controlled part of a cell's growth |
| What cells does mitosis happen to? | somatic cells |
| What cells does meiosis happen to? | egg and sperm cells |
| Are there cells that do not divide? | yes |
| How do different types of stem cells compare? | the genes within stem cells are the same, but they have different patterns in their gene expression |
| How do zygotes divide and produce more cells? | through the process of mitosis |
| What happens to cells during embryonic development? | cells increase in number and become more specialized |
| How do DNA and genes in different types of cells compare? | the DNA is the same, but different genes are activated |
| Even though all the cells in an individual organism come from a ______ ___, they can specialize into different types of cells. | single cell |
| How do different somatic cells in the same organism compare? | they contain the same genetic and descend from the same cell |
| What types of cells can stem cells produce? | cells that are identical to themselves or more specialized |
| When does the restriction point in the regulation of the cell cycle occur? | at the G1 checkpoint |
| Among the cells in the human body, ______ ____ contain 46 chromosomes whereas the _______ contain 23. | somatic cells; gametes |
| What is the imaginary line along which the chromosomes organize during mitosis? | the metaphase plate |
| What is density-dependent inhibition? | the phenomenon exhibited by most anchorage dependent cells that stop dividing once a critical cell density is reached |
| Because plant cells lack a cleavage furrow, they utilize a ____ _____ to divide into daughter cells. | cell plate |
| A specific kind of mutation causes defective proteins that participate in the formation of the cleavage furrow. Which of the following mitotic phases will be affected? | telophase |
| What is the best explanation for the failure to observe chromosomes through a microscope in human cells? | the cells are in the G0 phase |
| During which phase does DNA synthesis occur in the cell cycle? | S phase |
| What is the primary function of kinetochores? | to connect sister chromatids to fibers attached to the cell's poles |
| Which of the cell cycle phases are part of a dividing pathway? | G1, G2, M and S phase |
| Cells that will divide only if they are attached to an extracellular membrane are demonstrating _________ __________. | anchorage dependence |
| What are some tumor types that have migrated beyond their original location? | metastasis and malignant tumor; not benign tumors |
| Chromatin is a complex of ___ and ________. | DNA and proteins |
| How is the prokaryotic genome different than the eukaryotic genome? | prokaryotic genome is contained in a single DNA molecule |
| When does prometaphase occur? | before metaphase |
Created by:
alov9636
Popular Biology sets