Biology Cellular Flashcards
The cell is the fundamental unit of all living ___
things
Every function in biology involves a process that occurs within ___ or at the interface between cells
cells
All living things are ___ of cells
composed
The cell is the basic ___ unit of life
functional
The chemical reactions of life take place inside the ___
cell
___ arise only from pre-existing cells
cells
Cells carry genetic information in the form of ___. This genetic material is passed from parent cell to daughter ___
DNA, cell
There are millions of species of “living things” that can be divided into ___ kingdoms
six
Bacteria, Archaea, ___, Fungi, Plantae, and Animalia
Protista
Within these six kingdoms are two major types of cells: ___ and eukaryotic
prokaryotic
The word prokaryote means “before nucleus,” which alludes to the structure of these organisms as a whole: they do not contain ___ or membrane-bound organelles
nuclei
While eukaryotes possess all the cellular structures mentioned in this chapter, ___ only possess a cell membrane, cytoplasm
prokaryotes
According to the generally accepted fluid mosaic model, the cell membrane consists of a ___ bilayer with proteins embedded throughout
phospholipid
The ___ and many of the proteins can move freely within the membrane
lipids
Phospholipid molecules are arranged such that the long, nonpolar, hydrophobic, “fatty” chains of carbon and hydrogen face each other, with the phosphorus-containing, polar, hydrophilic heads facing ___
outward
As a result of its lipid bilayer structure, a plasma membrane is readily permeable to other small, nonpolar, hydrophobic molecules such as oxygen, and small ___ molecules, such as water
polar
Enclosed by the nuclear membrane, the ___ contains DNA wound around structural proteins called histones
nucleus
During DNA replication, DNA tightly winds around the ___, compacting (loose DNA) into chromosomes
histones
During transcription, however, DNA unwinds itself from the ___ allowing for transcription to occur
histones
In addition, the nucleus contains a dense structure called the ___ where ribosomal RNA (rRNA) synthesis occurs
nucleolus
Prokaryotes do not have ___ and therefore do not possess histones to organize their DNA into linear chromosomes
nuclei
Instead, prokaryotic ___ is organized into small circular chromosomes located in a region of the cell termed the nucleoid
DNA
Ribosomes facilitate protein production and are made of __ rRNA sequences, called ribosomal subunits
two
Although rRNA molecules are synthesized in the nucleolus of eukaryotes, they function either in the ___ as unbound ribosomes or on the outer membrane of the rough endoplasmic reticulum as bound ribosomes
cytoplasm