3: Cell Structure Flashcards
Resolution
The minimum distance apart that two objects can be in order for them to appear as separate items
Homogenate
The fluid that results from homogenisation
Photomicrograph
The image that is produced from a transmission electron microscope
Eyepiece Graticule
A glass disk that is placed in the eyepiece of a microscope. A scale is etched on the glass disk
Stage micrometer
A microscope slide that has a scale etched onto it
Eukaryotic cells
Cells that have a distinct nucleus and possess membrane-bound organelles
Prokaryotic cells
Cells that have no nucleus and no membrane-bound organelles
Nuclear envelope
A double membrane that surrounds the nucleus
Nuclear pores
Pores which allow the passage of large molecules out of the nucleus
Nucleoplasm
Granular, jelly-like material that makes up the bulk of the nucleus
Chromosomes
Consists of protein-bound, linear DNA
Nucleolus
A small spherical region within the nucleoplasm that manufactures ribosomal RNA and assembles the ribosomes
Cristae
Extensions of the inner membrane in mitochondria and provides a large surface area for the attachment of enzymes/proteins
Matrix
The remainder of mitochondria, containing proteins, lipids, ribosomes and DNA. the allows mitochondria to produce some of their own proteins
The chloroplast envelope
Double plasma membrane that surrounds the organelle
Grana
Stacks of thylakoids in chloroplasts
Thylakoids
In stacks of grana, contains the pigment chlorophyll
Chlorophyll
The photosynthetic pigment in thylakoids
Stroma
Fluid-filled matrix in chloroplasts, where the second stage of photosynthesis takes place
Rough endoplasmic reticulum
Has ribosomes present on the outer surface of the membranes
Smooth Endoplasmic reticulum
Lacks ribosomes on its surface and is often more tubular in appearance
Cisternae
Flattened sacs that Golgi apparatus are made of
Tissue
A collection of similar cells that perform a specific function
Epithelial cells
Cells that line the surfaces of organs and often have protective or secretory functions
Organs
Aggregation of several tissues that perform a specific role
Cell wall
A physical barrier surrounding plant cells and bacteria, e.g. made of cellulose in plants
Capsule
A mucilaginous layer of slime, covering bacteria
Plasmids
Small circular pieces of DNA, in bacteria
Capsid
A protein coat, that coats the nucleic acid of a virus
Attachment proteins
Essential to allow the virus to identify and attack to a host cell
Mitosis
The division of a cell that results in each of the daughter cells having an exact copy of the DNA of the parent cell
Interphase
The period when a cell is not dividing, but DNA is replicated and cell carries out its functions
Prophase
When the chromosomes first become visible and the spindle fibres develop
Metaphase
When the individual chromatids line up at the equator of the cell
Anaphase
When the spindle fibres pull the individual chromatids apart to the opposite poles of the cell
Telophase
When the chromosomes reach their respective poles and they become longer and thinner until they disappear
Cytokinesis
When the cytoplasm divides and the two identical daughter cells are formed
Binary fission
The process by which cells divide in prokaryotic cells
