Cells Flashcards
A scientist investigated the growth rate if the bacterium Bacillus sonorensis.
Describe how these bacterial cells replicate by binary fission.
-Replication of (circular) DNA
-Replication of plasmids
-Division of cytoplasm to produce daughter cells
A scientist measured the mass of bacterial cells in picograms.
1 pg = 1 x 10^-12 g
Calculate how many grans are in 720 pg.
7.2 x 10^-10 g
Suggest 2 ways in which the environmental conditions could be altered to increase the growth rate of bacteria.
- Increased glucose conc
- Increased respiration
- Increased oxygen conc
- Increased respiration
- Increased temperature
-Increased enzyme activity - Increased phosphate conc
- Increased ATP/DNA/RNA
- Increased nucleotide conc
- Increased DNA synthesis
Describe the role of a centromere in the process of mitosis.
- Holds chromatids together
- Attaches chromatids to the spindle fibres
-Allows chromatids to move to opposite poles
Mitosis is a cell process used by organisms throughout their lifetime.
Explain why mitosis is an important cell process.
- Allows for growth
- Can replace cells and repair tissues
- Produces genetically identical cells
- Asexual reproduction/cloning
Describe what occurs during interphase to prepare a cell for division
- DNA replication
- Chromosome becomes two chromatids
- DNA is checked for errors
- Centrioles replicate
Which organelle is not involved in the production and secretion of enzymes in eukaryotes?
-golgi apparatus
-ribosomes
-smooth endoplasmic reticulum
-vesicle
Smooth endoplasmic reticulum
Which of the following cell structures are present in prokaryotic cells?
-lysosomes
-nucleus
-ribosomes
-starch grains
Ribosomes
Which structures are found in animal and plant cells?
Cell membrane
Nucleolus
Which of these cell components contain ribosomes?
-chloroplast
-mitochondrion
-smooth endoplasmic reticulum
-cytoplasm
chloroplast
mitochondrion
cytoplasm
Which 3 organelles in eukaryotic cells
have a double membrane?
- Chloroplast
- Mitochondrion
- Nucleus
What is the function of nucleoli?
Formation of ribosomes
True of False?
Eukaryotic cells have linear DNA
true
True or False?
Eukaryotic cells only have small (70s) ribosomes
False
Where would cisternae be found in a cell?
Endoplasmic reticulum
Golgi apparatus
Which 2structures are found in both chloroplasts and mitochondria?
- 70s ribosomes
- circular DNA
True if False?
Differential staining is a common feature of electron microscopy
False
What can differential staining distinguish between?
- Different organelles
- Different types of cells
- Different types of organisms
What is meant by a microscope with high resolution?
The microscope can distinguish structures that are very close together
A culture of human cells had its cell surface membranes removed, releasing the cell contents.
This material became contaminated by bacteria.
The material was then centrifuged, separating the various cell structures according to size and mass.
Which cell structure would be separated along with the bacteria?
Mitochondria
