Week 2 "Formation" Flashcards
What is the generic components of a generic membrane?
Phospholipids- (bilayer formation)
Cholesterol- (membrane integrity and fluidity)
Proteins- (integral or peripheral membrane proteins–important for cell function)
Carbohydrates- attached to lipids or proteins-contribute to cell-cell recognition etc.
List the general role of biological membranes and describe each
Compartmentalisation- allows cell to carry out different metabolic reactions at the same time (generates different environments)
Electrochemical/membrane potential - semipermeable- ions may be controlled to serve function
Transport/protection- stops cell falling apart, monitors nutrient flow
Anchoring- interacts with proteins to anchor them in place- also interacts with cytoskeleton elements to maintain structure.
List 4 types of membrane transport.
Simple diffusion- (across membrane
Facilitated diffusion- (requires a channel or carrier protein)
Primary active transport- (uses ATP)
Secondary active transport (ion coupled transport)-using chemical gradient of an ion to transport a solute against its concentration gradient
Types of membrane protein transport
Uni-transport - one molecule
Co-transport - (Symport and antiport)
Role of Smooth ER and Rough ER
Smooth- hormones and lipids
Rough- (presence of ribosome)- protein production
Role of lysosomes and peroxisomes
Lysosomes- digestive organelle
Peroxisomes- detoxification
What is mitosis
Cyclical sequence of events resulting in production of 2 identical daughter cells
(somatic cells)
What is cell differentiation
The process in which a cell becomes more specialised.
What is a stem cell
They are undifferentiated cells which are capable of self renewing (making more of themselves) as well as differentiating into more specialised cell types.
Differentiate:
Totipotent
Pluripotent
Multipotent
T- most versatile- can differentiate to any cell
P- can give rise to all differentiated body cells but not entire organism
M- can give rise to more than one cell type (much more limited)
What is apoptosis and its role in embryo development
It is a programmed form of cell death.
In development ensures proper formation of fingers. etc
What is the central dogma of molecular biology?
DNA–>RNA–>Protein
What is DNA replication
Process in which DNA is replicated (usually before cell division)
Parental strand used as template for daughter strand.
What is transcription
DNA–>mRNA (RNA pol in nucleus)
What is translation
mRNA–> Protein (at ribosome in cytoplasm)
What are the universal features of the genetic code
- Three nucleotides per base (amino acid)
- non overlapping- (groups of 3 read in order)
- degenerate- more than one triplet can code for a particular amino acid.
What is some features of a chromosome structure.
- 2 chromatids (sister)
- telomeres -stable ends of a chromatid
- centromeres
- diploid organisms have 2 sets of chromosomes (2 allele options)
In translation what order do the tRNA enter the ribosome
1st enters the P site 2nd enters the A site both shift over- P tRNA moves to E and exits new tRNA enters in A site. order of A-P-E
What portion of the nuclear genome is gene coding
25% is genes/gene related
of this portion
10% coding DNA
Structure of nuclear genome
Structure of mitochondrial genome
Nuclear genome - (large) 1.DNA wrapped around histones 2. condensed into chromosome structure Mitochondrial genome- (small) 1. Small number of genes in plasmid configuration
What is a gamete
sex cells (haploid)
what is an Embryo
as the zygote divides into more cells it is then termed an embryo (in humans considered embryo up until the 9th week post fertilisation or 11 week gestational age
what is a zygote
fusion of male and female sex cell (diploid) (fertilised ovum)
what is a foetus
larger multicellular organism stage after embryo (yet to be born)
What is the ectoderm
give example of structures+cell types
the outermost layer of cells or tissue of an embryo in early development, or the parts derived from this. eg skin and nervous system.
What is the mesoderm
give example of structures+cell types
the middle layer of cells or tissues of an embryo, or the parts derived from this (e.g. cartilage, muscles, and bone).
What is the endoderm
give example of structures+cell types
The innermost layer of cells or tissue of an embryo in early development, or the parts derived from this eg gastrointestinal linings and pulmonary sytem
What are the three germ layers
Ectoderm
Mesoderm
Endoderm
Developmental events in the first trimester
Week 0- Last menstrual period
Week 2- Fertilization (sperm and ovum fusion)
Week 2 till Week 10 - embryogenesis and organogenesis (organs formed)
Developmental events in the second trimester
Week 13-16- sensory organ development
Week 16-20- fetus may begin to move (may be as late as week 25)
Week 24- 50% survival of foetus outside the womb
Week 24 - lungs develop further
Developmental events in the third trimester
Third trimester
Week 37- organs capable of functioning outside womb
Week 40- full term
Common methods to determine whether pregnancy is progressing normally.
Imaging- ultrasound to determine any physical abnormalities
foetal echocardiography- using a doppler ultrasound to view heart in more detail.
DNA sampling- to check for genetic disorders
Physical exam- assess mothers size, auscultate, palpate
