Human Development Flashcards
What is fertilization?
The union of sperm and egg cells, resulting in a zygote /w 46 chromosomes.
What is a zygote?
The single cell formed by the fusion of sperm and egg during fertilization, which undergoes mitosis to form an embryo.
What is cleavage?
Rapid cell division of the zygote without increasing its size leading to a cluster of smaller cells.
Describe the formation of a morula.
After several cell divisions, the zygote becomes a solid ball of cells called a morula.
What is a blastocyst?
A structure formed when the morula fills with fluid, consisting of a trophoblast (outer layer) and inner cell mass.
Define implantation.
The process by which the blastocyst attaches to the uterine lining, enabling further development.
What is human chorionic gonadotropin (hCG), and why is it important?
A hormone secreted by the trophoblast that maintains the corpus luteum, supporting early pregnancy.
What happens during gastrulation?
The embryo forms three primary germ layers (ectoderm, mesoderm, endoderm), setting the stage for organ formation.
What are the primary germ layers and their functions?
Ectoderm forms skin and nervous tissue, mesoderm forms muscles and bones, and endoderm forms internal organs.
Define morphogenesis and differentiation.
Morphogenesis is the development of form and structure, while differentiation is cell specialization for specific functions
What is neurulation?
The formation of the neural tube from the ectoderm, leading to the development of the brain and spinal cord.
What are the main changes during the fetal period (weeks 9-birth)?
Organ growth and maturation, with emphasis on brain and skeletal development and fat accumulation.
Describe the role of the placenta
The placenta supplies nutrients and oxygen, removes waste, and produces hormones essential for pregnancy.
What is the function of the umbilical cord?
It connects the fetus to the placenta, transporting nutrients, oxygen, and waste between the mother and fetus.
What are teratogens?
Agents like alcohol, drugs, and pollutants that can cause developmental abnormalities or birth defects.
What are the effects of Fetal Alcohol Spectrum Disorder (FASD)?
FASD causes growth deficiencies, brain damage, learning disabilities, and social challenges.
What hormones are involved in parturition?
Oxytocin (triggers contractions) and prostaglandins (enhance contractions and cervix dilation).
Describe the stages of labor
- Dilation stage (cervix opens); 2. Expulsion stage (baby is delivered); 3. Placental stage (afterbirth is expelled).
What is lactation?
Milk production initiated by prolactin and milk ejection stimulated by oxytocin.
How does the suckling reflex work?
Infant suckling triggers oxytocin release, causing milk ejection from mammary glands.
What is In Vitro Fertilization (IVF)?
A procedure where eggs are fertilized outside the body, then implanted into the uterus.
What is Artificial Insemination (AI)?
A process of directly placing sperm into the female reproductive tract.
What is Intracytoplasmic Sperm Injection (ICSI)?
A technique where a single sperm is injected into an egg to aid fertilization.
What is Gamete Intrafallopian Transfer (GIFT)?
Placing sperm and egg directly in the fallopian tube for natural fertilization.
What is surrogacy?
An arrangement where a surrogate carries a pregnancy for someone who cannot.
What are hormonal contraceptives?
Methods that use hormones to prevent ovulation, thicken cervical mucus, or alter the uterine lining.
What are barrier methods of contraception?
Devices like condoms and diaphragms that block sperm from reaching the egg.
Describe sterilization procedures.
Permanent methods like tubal ligation in females and vasectomy in males that prevent reproduction.
What is emergency contraception?
Pills or devices used after intercourse to prevent pregnancy by delaying ovulation or preventing implantation.
What are some ethical considerations regarding embryo use?
Concerns about the moral status of embryos created or discarded during IVF
Why is consent important in reproductive technology?
Ensuring all parties (donors, surrogates) understand rights and responsibilities
What are ethical concerns related to genetic screening?
Concerns about eugenics and the impact of choosing certain traits, such as “designer babies.”
What are the concerns regarding accessibility and equity in reproductive technology?
Ensuring that these technologies are affordable and available to all, not just a few.
Zona pellucida
Jelly layer around the egg cell that binds sperm for fertilization and prevents additional sperm from entering after one has fertilized the egg.
What is the corona radiata?
Layer of cells surrounding the egg that provides nutrients and protection. It also assists in the sperm’s binding and penetration during fertilization.
What is the trophoblast?
Outer layer of cells in the blastocyst that provides nutrients to the embryo and develops into part of the placenta, helping in implantation and supporting early pregnancy.
What is the ectoderm?
Outermost germ layer that develops into the skin, nervous system, and sensory organs.
What is the mesoderm?
Middle germ layer forms muscles,bones,the circulatory system, and internal structures like kidneys and reproductive organs.
What is the endoderm?
Innermost layer that develops into the lining of the digestive and respiratory tracts as well as organs like the liver and pancreas.
What is neuralation?
Process in early development where the ectoderm forms the neural tube, which will develop into the brain and spinal cord. This is a significant step in the formation of the central nervous system.
What is the amnion
Membrane that surrounds the developing embryo and fills with amniotic fluid to protect the embryo from physical shock and dehydration and whatnot.
What is the chorion?
Outermost membrane, involved in the formation of the placenta. It facilitates gas exchange and nutrient exchange between mother and embryo.
What is the allantois?
Involved in waste disposal and gas exchange. It contributes to the formation of the umbilical cord and helps in the development of blood vessels in the placenta.
What does the yolk sac do
Sit pretty and do fuck all for mammals. In non mammals it provides nutrients n shit.
