physiology- atoms, molecules and cells

Purine bases

Adenine and guanine

How many rings do purine bases have?

Double rings of nitrogen and carbon

How does RNA differ from DNA?

Single chain of nucleotides

Ribose sugar

Thymine is replaced by Uracil

total genetic information coded in the DNA

genome

sequence of DNA nucleotides that specifies the sequence of amino acids in a single polypeptide chain

gene

46 chromosomes in humans

true

chromosome contains a strand of DNA that is wrapped and tightly coiled around special packaging proteins

histone

Clusters/complexes of DNA coiled around histones

Nucleosomes

X X

female

XY

Male

Only 61 of the 64 possible triplets are used to specify amino acids.

true

what does helicase do?

Breaks the hydrogen bonds between the bases on the DNA strand

Transcription enzyme

RNA polymerase

Sections of a gene encoding amino acids

exon

Sections of a gene not coding for amino acids

intron

skeletal muscle

under voluntary control. attaches to bones or skin

cardiac muscle

involuntary control. only found in the heart

smooth muscle

involuntary control. surrounds tubes

neuron- neuron

passes on electrical signals

neuron-gland

secretes a chemical signal

neuron to muscle

contraction

epithelial cells are specialised for..

• selective secretion and absorption of ions and organic molecules

• protection

types of epithelial cells

• cuboidal

• columnar

• squamous

• ciliated

do epithelial cells form barriers with tight junctions?

yes

tight junctions

tight junctions restricts the movement of fluids between adjacent cells due to the presence of integral proteins that fuse together to form a firm seal.

location to find tight junctions in an epithelial cell

the bladder- prevents the escape of fluids that would compromise the urine

name the three types of anchoring junction

desmosomes, hemidesmosomes, and adherens

desmosomes

hold neighbouring cells together by way of cadherin molecules which are embedded in protein plates in the cell membranes and link together between the adjacent cells. 

Hemidesmosomes

Link cells to components in the extracellular matrix, such as the basal lamina. They use adhesion proteins called integrins rather than cadherins.

adherins

Characterized by the presence of the contractile protein actin located on the cytoplasmic surface of the cell membrane.

 Influence the shape and folding of the epithelial tissue.

Use either cadherins or integrins depending on whether they are linking to other cells or matrix.

Gap Junctions

Forms an intercellular passageway between the membranes of adjacent cells to facilitate the movement of small molecules and ions between cells. These junctions thus allow electrical and metabolic coupling of adjacent cells.

apical side and basolateral sides of the epithelium have different functions

yes

connective tissues

connect, anchor and support structures of the body

types of connective tissues

loose connective, dense connective, bone and cartilage, adipose and blood

what surrounds cells?

extracellular fluid and the extracellular matrix. These consist of proteins, polysaccharides and in some cases minerals

Two general functions of the extracellular matrix

provides the scaffold for cellular attachments

transmits information to cells to regulate activity, such as growth, migration and differentiation

Protein fibers consist of..

collagen- 1/3 of all body proteins

elastin

the minimum type of tissue an organ has to have

two

is extracellular fluid in or outside the cell

outside the cell

interstitial fluid

name for the extracellular fluid around and between cells.

whats the space containing the interstitial fluid called?

the interstitium

which comes first transcription or translation?

transcription

Transcription steps

This process is catalysed by the enzyme RNA polymerase This enzyme travels along the template strand making a copy The copy is said to be complimentary to the original strand Spliceosomes edit the mRNA before it leaves the nucleus.

what do spliceosomes do?

remove introns from the primary mRNA transcript to form mature messenger RNA or mature RNA

how many mm in 1m

1000

10mm in cm

1cm

1mm in micrometers

1000 micrometers

cytoplasm

the region outside the nucleus (including organelles)

cytosol

the fluid portion of the cytoplasm surrounding the organelles

intracellular fluid

all fluid inside a cell, including inside all organelles including the nucleus