numbers Flashcards
collagen
Accounts for 40 percent of the total protein in the human body.
proteoglycan
May consist of up to 95 percent carbohydrate.
cystic fibrosis
- Most common lethal genetic disease in the US.
- Strikes 1/2,500 people of European descent but is much rarer in other groups
- Among people of European descent, 1/25 are carriers
- Untreated: die before 5th birthday. Treated: >half survive into late 20s or even 30s and beyond
sickle-cell disease
- Most common inherited disorder among people of African descent.
- Affects 1/400 African-Americans
- 1/10 Af-Amer have sickle-cell trait
Huntington’s disease
In the US: afflicts 1/10,000 people.
PKU
phenylketonuria; occurs in 1 of every 10,000 to 15,000 births in the US
amniocentesis
14th - 16th wk of pregnancy
chorionic villus sampling (CVS)
as early as 8th - 10th wk of pregnancy
vascular plants
Comprise 93 percent of all extant plant species
angiosperms
Nearly 90 percent of living plant species are angiosperms. 250,000+ species of angiosperms.
plant evol
During the first 100mill years of plant evolution, bryophytes/bryophyte-like plants were the prevalent vegetation.
seed plants’ origin
360 million years ago.
- gymnosperms: 305 million
- angiosperms: 160 million
plants and drugs
25% of prescription drugs contain an active ingredient from plants, typically seed plants.
The genome of which tree species has been sequenced?
The poplar (Populus trichocarpa)
Some insights into the evolution of 2ndary growth have been achieved by studying which plant?
The herbaceous plant Arabidopsis thaliana.
most prevalent disaccharide
sucrose aka table sugar
cellulose
plants produce almost 100 billion tons of it per year globally. it’s the most abundant organic compound on earth.
proteins account for __ of the dry mass of most cells
> 50 percent
the first 3-D structure for a protein was worked out for
hemoglobin and a related protein
light microscope magnification and resolution
can magnify effectively to about 1,000x the actual size ;
cannot resolve detail finer than (200 nanometers)
electron microscope resolution
theoretical: .002 nm
in practice: no smaller than 2 nm
smallest cells and their size
mycoplasmas; diameters btwn 0.1 and 1.0 micrometers
typical bacteria size
1 to 5 micrometers in diameter; 10x the size of mycoplasmas
eukaryotic cells size
typically 10 - 100 micrometers in diameter
nucleus size
5 micrometers in diameter
nuclear membrane
- the 2 membranes are separated by a space of 20 to 40 nm
- pores are 100 nm in diameter
plasma membrane thickness
8 nm
aquaporins
each one allows entry of up to 3 billion water molecules per second, passing single file thru its central channel, which fits 10 at a time
membrane potential
ranges from -50 to -200 millivolts (mV)
enzyme rate
typically acts on about 1000 substrate molecules per second; others are much faster
optimal temp of human enzymes
most human enzymes have optimal temps of about 35 to 40 deg C (close to human body temp)
optimal pH of human enzymes
6 to 8, but there are exceptions
number of known eyzmes
4,000
medicines and GPCRs
up to 60 percent of all medicines used today exert their effects by influencing G protein pathways
cell-surface receptors
- make up 30 percent of all human proteins
- make up 1 percent of the proteins whose structures have been determined by x-ray crystallography (their structures are hard to determine)
largest family of cell-surface receptors
nearly 1,000 GPCRs
genes and protein kinases
about 2 percent of our own genes are thought to code for protein kinases
cells and protein kinases
a single cell may have HUNDREDS of diff kinds, each specific for a diff substrate protein
cAMP concentration
boosted 20-fold in a matter of seconds when the enzyme ADENYLYL CYCLASE catalyzes the synthesis of many molecules of cAMP
Ca2+ level in animals
Ca2+ level in the blood and extracellular fluid of an animal is often >10,000 times higher than that in the cytosol
details of apoptosis were worked out by researchers studying which organism?
Caenorhabditis elegans, a small soil nematode
DNA per cell
- 2 meters long – 250,000x greater than the cell’s diameter
how many cells in your body
200 trillion
human gamete: possible chromosome combos
8.4 mill (2^23)
Duchenne muscular dystrophy
affects 1/3,500 males born in US
nucleotide pairs per human cell
6 billion
DNA replication error rate
- before proofreading: 1 in 100,000
- after: 1 per 10 billion nucleotides
Okazaki fragment length
- E coli: 1,000 - 2,000 nucleotides long
- eukaryotes: 100 - 200
chromatid width
700 nm
rate of transcription
40 nucleotides per second in eukaryotes
RNA splicing numbers
- avg length of a transcription unit along a human DNA molecule is about 27,000 np
- however, it only takes 1,200 nucleotides in RNA to code for the avg-sized protein of 400 AA
human gene expression in cell
typical human cell might express about 20 percent of its protein-coding genes at any given time. highly differentiated cells express an even smaller fraction
protein-coding DNA
accounts for only 1.5 percent of the human genome
regulation of human gene expression
at least one half of all human genes may be regulated by miRNAs
ras and p53
mutations in ras occur in about 30 percent of human cancers, and mutations in p53 in more than 50 percent
cancerous viruses
worldwide, viruses seem to play a role in about 15 percent of the cases of human cancer
known plant species
290,000
