Bio Key Words and definitions Flashcards
tetrad
term for a group of 4 sister chromatids (inside in the homologous chromosome pair)
bivalent
the pair of the 2 homologous chromosomes.
homologous chromosomes
2 chromosomes that are matching, in terms of structure and contain the same types of genes in the same location.
chiasmata
where the 2 homologous chromosomes overlap, and is the point of breakage during meiosis.
recombinant chromosomes
formed when large sections of the DNA double helix move from one chromosome to another, increasing genetic diversity.
- formed in prophase 1
Synaptonemal Complex
the tripartite proteinacious structure, that forms between the homologous chromosomes, serving as a scaffold, holdin them in place and ensuring accurate crossing over.
olfactory nerve
the nerve that sends impulses to the brain regarding how something smells.
Hemopoiesis / hematopoiesis / hematogenesis / hemogenesis
the process of making new blood cells, in the bone marrow
hematopoietic stem cells
an immature cell that can develop into all types of blood cells.
erythropoiesis
the process of erythrocytes production
erythrocytes
Red Blood cells
leukocytes
type of bood cellsm that defend against pathgoens, made in the bone marrow and found in the blood and lymph tissue.
Megakaryocytes
a large bone marrow cell, with a lobed nucleus, that fragements into platlets / thrombocytes
Leukopoiesis
the process of producing leukocytes, which is stimulated by certain messenger molecules.
hemostasis
the mechanism that stops bleeding, through vascular spams, platlet plug formation and coaguation.
thrombocytes
platelets
agglutinogens
like antigens - proteins produced by foreign cells or genetic material.
sinusoid
a specialised capillary with large spaces in the cappillary wall, allowing blood cells and proteins to be exchanged between the blood and tissues.
fribrinolysis
the degradation of the fibrin network of a blood clot.
agglutinins
they are antibodies, produced by the body as part of an immune response.
they cause agglutination or the clumping of the antigens.
Rh factors
inheited proteins that are found on the surface of RBCs. when finding blood groups, Rh factors state if someone is either positive or negative.
- if protein present = +ve blood type
- if lacks Rh = -ve blood type
Keratinocytes
a majour cell types of the epidermis, the outermost layers of the skin
desmosomes
specialised adhesive protein complexes, that localise intercellular junctions and are responsible for maintaining the mechanical integrity of tissues.
defensins
cysteine-rich cationic proteins, for direct antimicrobial activity, or immune signalling activities or both.
the complement system
made up of distinctive plasma proteins, that take part in opsonisation, chemotaxis, cell lysis, and agglutination (clumping)
chemotaxis in terms of immunity
process of attracting macrophages and neutrophiles, as a response of signalling molecules.
Phosphofructokinse
the allosteric enzyme that catalyses the phosphorylation of fructose-6-phosphate using ATP = fructose-1,6-diphosphate in glycolysis.
exergonic reaction (vs. exothermic)
a spontaneous reaction, that release energy from the system to the surroundings.
unlike exothermic, which has nothing to do with spontaneity.
pyruvate dehydrogenase
the enzyme that catalyses the cnversion of pyruvate to acetyl-coenzyme A, in the links reaction.
obligate anaerobes
organisms that can only survive in oxygen free environemts, cos O2 is toxic for them.
Facultative anaerobes
orgs that prefer O2 rich environments, but can also survive without O2.
obligate aerobes
orgs that can only survive with oxygen. they can take part in anearobic respiration, but cannot survive on it.
HLA complex - Human Leukocyte antigens
they are genes in majour histocompatibility complexes (MHCs) that help code for proteins that differentate between self and non-self.
Histocompatibilty test
aka the HLA test, done to determine the compatibiltiy between a donor and a recipient for transplantation purposes.
Centrosomes and centrioles
cetrosomes are found in the cell and are made up of 2 cetrioles, or microtubule rings.
function - chromatid seperation in cell division.
condensin proteins
the chromatin coils and condenses with condensin protiens, to form visible chromosomes in prophase.
cohesin proteins
they glue replicated sister chromatids together until they are split as anaphase.
phagocytosis
type of endocytosis that involves large, particulate substances
pinocytosis
endocytosis of substances dissolved in extracellular fluid.
peroxisomes
an organelle that -
1. breaks down org, material into H2O2 and then
H2O2 -> H20 + O2
- Involved in the lipid synthesis, like cholesterol and phospholipids that are found in the heart and brain tissue.
- prevents kidney stones from forming.
zona pellucida
the protective (glycoprotein) membrane surrounding the egg, that the sperm recognises and binds to.
chordate phylum
a feuture resulting from the notochord to define into the notochrod.
Apoptosis
Programmed cell death, controlled and organsised, involving important mediators called caspases. crucial in development, tissue homeostasis, and elimination of damaged cells.
Necrosis
uncontrolled cell death - form injury infection or disease.
caspases
they are cysteine proteases, involved in apoptosis.
autolysis
self digestion of cells after death
rigor mortis
postmortem stiffening of muscles cos of the depletion of ATP.
corpus luteum
a yellow secreting hormone, that sectretes eastrogen and progesterone.
- the hormone is formed at the ovary where an ovum has been released during ovultation.
gestational period
time between conception and birth, fertilisation occurs at week 2 of the gestation period.
Sertoli cells
Somatic cells, where spermatids develop around in it of the tubules of the testi
Genetic code redundancy (degenerate)
when amino acids are specified by more than one mRNA codon.
non-overlapping genetic code
triplets or codons are read in a sequence and are seperate from each other.
- bases arent shared amongst each other.
universal genetic code
the same bases code for the same amino acids for all living organisms.
which chromosome X or Y carries more genes
X is a larger chromosome, so most genes are only carried on X
= X-linked genes.
