Chapter 9 Flashcards
Define extranuclear inheritance
Inheritance of things other than DNA. AKA epigenetic inheritance
What do sex cells contain? (5 things)
- DNA
- organelles
- metabolites / nutrients
- RNA molecules
- pathogens/microbes
Comparatively, is DNA more or less changeable than organelles, RNA, and nutrients?
DNA is less changeable. Organelles, RNA, and nutrients are all environment-sensitive
What does epigenetics influence?
Intelligence
Physical fitness
RIsk of chronic disease
Metabolic health
Define zone pellucida
A glycoprotein containing the ova. Allows for protection of ova and sperm binding
Define corona radiata
Cells surrounding ova that provide nutrients
Does the ovum or sperm contribute more mitochondria?
Ovum contributes way more
What can damage the components of the ova?
Poor lifestyle choices can damage the corona radiata and zone pellucidum. This results in nutrient-deficient ovum and reduced fertility.
*Can also alter mitochondrial function
Altered mitochondrial function affects what?
The offspring’s metabolism
What is the main factor that alters mitochondrial function?
Overnutrition / poor diet
Are unhealthy mitochondria passed down?
Yes. Through F1, F2, and even F3 generations.
What does mitochondrial DNA create?
mtDNA makes tRNAs, rRNAs, and the 13 proteins involved in oxidative phosphorylation.
Mutations in mtDNA causes what?
metabolic and other health issues. These issues are passed to offspring maternally
Are mitochondrial mutations or nuclear mutations more common?
Mitochondrial
What type of molecules do mitochondria produce?
Reactive oxygen species (ROS)
What are ROS?
Reactive oxygen species, which are reactive molecules that damage lipid, proteins, and DNA through oxidative stress
Define oxidative stress
Damage to lipids, proteins, and DNA by ROS
What will cause excessive ROS?
Overnutrition, low antioxidants, and other stressors
What can maternal mitochondrial defects contribute to:
Aging
T2D
Autism
Artherosclerosis
Infertility
Neurodegenerative disease
Cancers
Personality/psychiatric disorders
Define acrosome
membrane-bound organelle produced from the golgi that is full of digestive enzymes
What are the enzymes found in the acrosome and what do they do?
Acrosin - breaks down zona pellucida
Hyaluronidase - separates and moves through corona radiata
What is the sperm packed full of?
RNA - brings microRNAs, tRNA fragments, and others.
What does sperm influence?
The gene expression of the zygote.
What determines the composition of sperm RNA?
the father’s lifestyle. This RNA influences offspring’s health
Define seminiferous tubules
Where sperm is first produced
Define spermiogenesis
Maturation of sperm in the epididymis
What occurs in the epididymis?
Spermiogenesis
When does paternal lifestyle impact sperm RNA the most?
During spermiogenesis.
What is a sperms journey?
Seminiferous tubules -> epididymis -> vas deferens -> prostate and seminal vesicles
Define seminal fluid
Fluid picked up from the prostate and seminal vesicles that contain nutrients, antimicrobials, and more.
What does transcriptionally inert mean?
A cell doesn’t produce new RNA.
How do sperm cells receive RNA?
RNA is deposited from epithelial cells in the epididymis.
Define epididymosomes
Where RNA is packed into. This vesicle fuses with other sperm to release RNA inside.
What influenced epididymosome RNA?
Paternal conditions like stress, physical activity
