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
Life Exam
| Question | Answer |
|---|---|
| Hierarchy of Life? | Atoms, molecules, organelles, cells, tissues, organ, organ system, organism, population, community, ecosystem, biosphere. |
| Six criteria for life? | Regulation/Homeostasis, organization, ability to reproduce/replicate, need for energy/energy processing, growth and development, response to stimuli. |
| What is regulation/homeostasis? | All living things must have multiple regulatory mechanisms to coordinate internal functions and cope with environmental stresses. |
| What is organization? | Living things are organized in membrane-bound cells. All living things are made of one or more cells, and cells have a plasma membrane that forms its selectively permeable boundary. |
| What is the ability to reproduce/replicate? | All organisms are capable of producing more of their own kind. |
| What is the need for energy/energy processing? | All organisms need energy and they obtain and process it in different ways. |
| What is growth and development? | All organisms start out in an immature form and get bigger and/or more complex. |
| What is response to stimuli? | All organisms are capable of reacting to their environment. Store genetic information. All organisms contain DNA that codes for necessary proteins. |
| What is the main difference between prokaryotic and eukaryotic cells? | Eukaryotic cells have a nucleus and membrane-bound organelles; prokaryotic cells do not. |
| What are things common to all cells? | Cell/plasma membrane, cytosol/cytoplasm, ribosomes, and DNA/genetic material. |
| Why do all cells have plasma membranes? | Cells need a selectively permeable boundary. |
| Why do all cells have cytosol/cytoplasm? | Cells have a jellylike filling that is aqueous. |
| Why do all cells have ribosomes? | Ribosomes are needed to produce proteins. |
| Why do all cells have DNA/genetic material? | Cells have instructions to tell them what to do. |
| What is a necessary characteristic of all living things? | They must conduct metabolic processes - metabolism is all the chemical reactions that happen in a cell. Metabolism includes all the anabolic and catabolic reactions occurring in the cell. |
| Why do mitochondria and chloroplasts have double membranes? | When they lived on their own, they had a single membrane. When they were taken in by a larger cell, they developed a second membrane derived from their host cell (endosymbiont theory) |
| Why do cells have different shapes and sizes? | Cells come in all shapes and sizes to be able to do all the various things in our bodies. Form dictates function, so the cells that cover a surface might be flat, and cells that conduct electrical impulses (like nerve cells) might be long. |
| What limits the size of a cell? | A decreasing surface area-to-volume (SA/V) ratio limits how large a cell can get. As a cell grows larger, its volume increases faster than its surface area. |
| Which of the proteins involved in DNA replication are enzymes? | All of the proteins in DNA replication are enzymes. Enzymes are proteins that catalyze/facilitate chemical reactions. Only the SSBs are not enzymes |
| Explain which enzymes in DNA replication are catabolic or anabolic (or both) and why. | The enzymes that catalyze cat reactions are helicase, topo, and DNA pol I. They all break bonds creating smaller molecules. The primase, DNA pol III, topo, and ligase catalyze anabolic reactions because they work to create bonds making a larger molecule. |
| Why are the two template strands of DNA replicated differently? | Because DNA is antiparallel, but it only can be built by adding nucleotides in the 5' to 3' direction. Therefore, on the leading strand DNA is replicated continuously, but on the lagging strand, replication is discontinuous. |
| What are the main phases of the cell cycle? | Interphase, which consists of G1, S, and G2. |
| What is G1? | G1 is a period of growth in which the cell grows, begins replicating its organelles, builds energy stores and proteins that are necessary in S phase. Also checks DNA for damage. |
| What is S? | S is where the new chromosomes are synthesized. |
| What is G2? | G2 is another period of growth where the cell checks the new chromosomes for errors and prepares for mitotic division. |
| What is mitotic division? | Mitotic division includes karyokinesis or mitosis which is prophase, metaphase, anaphase and telophase. This involves the division of the DNA. The second half of mitotic division is cytokinesis in which the cytoplasm and the organelles are divided. |
| Why do the chromosomes condense? | The chromosomes condense because this helps to ensure that they are evenly distributed during mitosis. |
| How is a sister chromatid different than a homologous chromosome? | Sister chromatids are identical to each other because they are duplicated chromos Homo chromos are not identical to each other because one is inherited from each parent. Homo chromosomes do contain the same genes on them, but may have different alleles. |
| When in the cell cycle would histones be made? At what point would histone synthesis be switched on and off? | Histones would be made in G1 of Interphase or in the beginning of S phase to prepare for the new chromosomes which will be made throughout the S phase. Histone synthesis would be switched off after the chromatin is formed so that may be in G2. |
| When in the cell cycle do the organelles begin to replicate, and why isn't it during mitosis? | Organelles begin to replicate in G1. The organelles couldn't begin to replicate in mitosis because chromosomes are to densely compacted to allow for the transcriptional machinery to access the DNA and make the necessary components to build the organelles. |
| Why is cytokinesis is different in plant and animal cells? | One way in which the plant and animal cells differ is that plants have a cell wall. Therefore, it would take a more complex mechanism to help divide the plant cells and reform the cell wall around the 2 daughter cells. |
| What happens at G1 checkpoint? | Checks for DNA damage and checks for adequate reserves and cell size. |
| What happens at G2/M checkpoint? | Check cell size and protein reserve and check for proper DNA replication. |
| What happens at M/Spindle checkpoint? | Check for proper attachment of sister chromatids to the spindle. |
| What are the three mechanisms to ensure that the DNA is a faithful copy of the original (parent) chromosomes? | 1 DNA replication is semi-conservative, so one strand of DNA is acting as the template for the new strand of DNA 2 DNA pol has the ability to proofread and catch its own mistakes 3 there are additional proteins that fix any mistakes in DNA synthesis |
| What are three reasons a cell might undergo apoptosis? | 1 is that the cell is no longer needed. 2 is that the cell has encountered a mutagenic event and the DNA becomes damaged and it can't be repaired. 3 is the newly formed copies of DNA are not formed correctly and can't be repaired. |
| Why does it require multiple mutations for cancer to occur? | The cell cycle is regulated by a number of different proteins, both pos and neg regulators. These proteins work together to control the checkpoints throughout the cell cycle. A number of mutations would have to occur to result in the loss of a checkpoint. |
Created by:
chloesrice
Popular Biology sets