(LE 1) Cell Structure & Genetic Control Flashcards
What is a cell?
Basic unit of structure and function in the body
What are the three common characteristics of a typical human cell?
- plasma membrane
- nucleus (not all mature cells)
- cytoplasm
What is an organelle?
cytoplasmic structures that perform specialized functions for the cell
What is the structure and function of the plasma membrane?
Phospholipid bilayer; barrier between intracellular and extracellular environments
What is the function of integral proteins and peripheral proteins?
Integral (transmembrane) protein: interact with fatty acid tail. Span across entire membrane
Peripheral protein: embedded on just one side of the membrane
function:
- structural support
- transport
- enzymatic control of cell processes
- receptor for hormones and other molecules
- self markers for immune system
What is bulk transport?
Way cells move large molecules and particles across PM
What type of bulk transport is pictured?
phagocytosis
What type of bulk transport is pictured?
Receptor mediated endocytosis (more specific)
What type of bulk transport is pictured?
Pinocytosis - cell drinking (non-specific)
What type of bulk transport is pictured? What specific organelle helps to facilitate it?
Exocytosis - exports products into extracellular fluid
- secretory-vesicles
What is a cytoskeleton?
latticework of microfilaments and microtubules filling cytoplasm
- gives cell structure
- form tracks to transport products around cell
What are lysosomes?
organelles containing digestive enzymes and digested matter
What are peroxisomes?
organelles containing oxidative enzymes
- involved in liver detoxification
- break down H2O2
What is an endoplasmic reticulum?
system of membranes specialized for synthesis or degradation of molecules
What is a rough ER?
contains ribosomes for protein synthesis
What is a smooth ER?
contains enzymes for steroid synthesis and inactivation
What is the golgi apparatus?
- lysosomes and secretory vesicles are formed here
Where is RNA made and stored in the cell?
Nucleolus
What is a chromatin?
DNA combined with protein creating a threadlike material that makes up chromosomes
What is a euchromatin?
part of chromosomes active in transcription
What is a heterochromatin?
highly condensed region where genes are permanently inactivated
What are genes?
lengths of DNA that code for proteins
What is gene expression?
process where Genes in our DNA are converted into a protein
What is transcription?
occurs when DNA sequence in a gene is turned into an mRNA sequence. (Happens in nucleus)
