Developmental exam 2

What do developmental biologists study within embryos?

Forces that cause cells to take on their fate during development.

What is differentiation?

The process producing overt change in appearance or biochemistry in cells.

What is specification in developmental biology?

A labile state where cells will differentiate in a neutral environment, having information about potential outcomes.

What does determination refer to in cell fate?

Cells that will differentiate autonomously, even if placed in another region of the embryo; fate is set and irreversible.

What pattern of development is seen predominantly in invertebrates?

Mosaic developmental pattern resulting from autonomous specification.

What is Macho development?

A localized development in the egg that is maternally derived, containing muscle-specific actin.

What is syncytial specification?

Formation of one cell with many nuclei due to incomplete cell division.

How do embryonic cells interact in conditional specification?

They exhibit flexible fates and can form whole embryos when isolated.

What are the possible experiments to determine commitment patterns in a species?

Find it, lose it, move it.

What does 'find it' mean in experimental terms?

Identifying the presence of a substance or factor in developmental processes.

What is the implication of 'lose it' in experiments?

Removing a factor and observing the consequences to see if it is necessary.

What is paracrine signaling?

Cellular communication where factors affect adjacent cells over longer distances.

What role do cadherins play in development?

They are calcium-dependent adhesion molecules that mediate cell-cell adhesion.

What is the significance of mesenchymal cells?

They are undifferentiated germ cells responsible for developmental processes.

What are CAMs and their role in morphogenesis?

Cell Adhesion Molecules that assist in sorting, ordering, and movement of cells during development.

What are the main types of signaling interactions?

Juxtacrine signaling and paracrine signaling.

What defines competence in developmental biology?

The ability of a responding cell to react to inductive signals.

What does induction refer to in cellular development?

One cell type influencing the behavior of another nearby cell.

What is the primary function of integrins in development?

To form dimers that mediate cell adhesion and signaling.

Why is the eye formation in Xenopus a notable example of induction?

It illustrates how different embryonic structures can cause reciprocal inductive events.

What can happen if there is a mutation in proteins involved in induction?

It may lead to failures in inductive interactions between cells.

What occurs during the process of gastrulation?

Rearrangement of cells in the blastocyst to form different germ layers.

What does the term 'bilaterally symmetrical animals' refer to?

Animals whose body plans can be divided into left and right halves.

What is the end result of the process of fertilization?

Formation of a zygote from the fusion of sperm and egg.

What stages mark the development in humans?

Fertilization, blastocyst stage, implantation, gastrulation, organogenesis, fetal growth, and birth.

What are the specialized functions of the sperm tail?

To provide motility for the sperm to reach the egg.

How do cortical granules function in the ovum?

They prevent polyspermy after fertilization.

What is IVF and how does it address infertility?

In Vitro Fertilization, it can bypass some issues like sperm motility or blockages in the reproductive tract.

What are the differences between internal and external fertilization?

Contact recognition, prevention of polyspermy, and environment for fertilization can vary.

What are the potential consequences of polyspermy?

It can lead to triploidy, where the zygote has an extra set of chromosomes.

How does age affect fertility in females?

Females stop producing eggs around menopause, affecting their ability to conceive.

What information do cadherins provide in embryonic cells?

They determine tissue-specific adhesion and influence cell interactions.

What is a knockout mutation?

A genetic alteration that inactivates a gene, often used to study gene function.

What is the role of morphogens in embryonic development?

They induce cellular differentiation based on concentration gradients.

Define 'cell adhesion'.

The process by which cells interact and attach to other cells and surfaces.

What is the function of the acrosomal vesicle in sperm?

It facilitates the reaction necessary for fertilization.

How does signal transduction contribute to developmental processes?

It mediates communication between cells, affecting their behavior during development.

What are the consequences of endocrine disruptors in fertility?

They can interfere with hormonal signaling necessary for reproductive functions.

Why is integrin binding important during development?

Integrins play a crucial role in cell migration and tissue formation.

What is the significance of E-cadherin in cancer?

Loss of E-cadherin is often associated with cancer cell invasion.

What are the roles of extracellular matrices during development?

They provide structural support and biochemical signals essential for tissue development.

What mechanisms can lead to ectopic pregnancies?

Often related to untreated STDs or other reproductive tract issues.

How does the zona pellucida function during fertilization?

It protects the egg and prevents polyspermy.

What does the term 'cleavage' refer to in early development?

The series of rapid cell divisions that transform the fertilized egg into a multicellular embryo.

What is the role of the zygotic genome during early development?

It becomes activated during gastrulation, influencing further development of the embryo.

What factors can affect the interaction of cells during development?

The type and density of cell adhesion molecules (CAMs) and extracellular matrix components.

What research method tests cellular competence for induction?

Reaggregation experiments to see if cells can respond to signals.

What experiment illustrates conditional specification?

Isolated blastomeres forming complete embryos when placed in the right environment.

What role does actin play in sperm motility?

It's involved in the movement of the tail, helping propel the sperm.

What is the embryonic induction timeline?

It describes the series of inductive signals that occur during early embryogenesis.

How does the organization of the dorsal blastopore lip affect development?

It guides proper axis formation in the embryo.

What is meant by 'mosaic' development?

A development pattern where each cell has a predetermined fate, typical in certain invertebrates.

What is dorsal vs. ventral specification?

It refers to the differentiation of cells that will form the back (dorsal) or belly (ventral) of an organism.

How does the maternal environment influence embryonic development?

The egg provides cytoplasmic determinants that influence the early developmental fate of cells.

What is the significance of reciprocal inductions during development?

It indicates ongoing communication between different cell types throughout differentiation.

What is 'ingression' during development?

The movement of epithelial cells to become individual mesenchymal cells.

What are morphogens and their role in cell differentiation?

They are signaling molecules that provide positional information to cells, leading to differential responses.

What is the importance of the ECM during morphogenesis?

It provides the structural framework that guides cellular movements and organization.

What does the term 'transforming growth factor-beta' (TGF-B) refer to?

A family of factors involved in cellular differentiation and proliferation during development.