Introduction to Developmental Biology

Question 1

What is Developmental Biology fundamentally the study of?

Answer 1

How an egg becomes an adult organism

Question 2

What term describes the course of an organism’s development from inception to adulthood?

Answer 2

Ontogeny

Question 3

What process involves a fertilized egg dividing and activating gene expression?

Answer 3

Developmental process

Question 4

What does modern developmental biology integrate and study?

Answer 4

Genetic control of cell growth, differentiation, and morphogenesis

Question 5

What is the starting cell of most animal development?

Answer 5

Zygote

Question 6

What is a zygote?

Answer 6

Single fertilized egg

Question 7

What early process establishes the body plan during embryonic development?

Answer 7

Axis specification

Question 8

What is axis specification?

Answer 8

Establishment of body plan axes during early embryonic development

Question 9

What is the organization of differentiated cells into complex structures called?

Answer 9

Tissue organization (Patterning)

Question 10

What is cephalization?

Answer 10

Concentration of nervous tissue and sensory organs at the anterior end (head)

Question 11

What developmental process involves a dramatic change in body form through stages?

Answer 11

Metamorphosis

Question 12

What are the stages of incomplete metamorphosis?

Answer 12

Egg → Nymph → Adult; nymph resembles small adult

Question 13

What are the stages of complete metamorphosis?

Answer 13

Egg → Larva → Pupa → Adult; larva differs significantly from adult

Question 14

Does development stop at birth or adulthood?

Answer 14

No, development is lifelong

Question 15

What is the process by which cells become different from one another?

Answer 15

Differentiation (Cellular differentiation)

Question 16

What is differentiation?

Answer 16

Cells change type and specialize, generating cellular diversity

Question 17

How many cell types can differentiation produce in complex organisms?

Answer 17

Over 210

Question 18

What process organizes cells into tissues, organs, and systems?

Answer 18

Morphogenesis

Question 19

What is morphogenesis?

Answer 19

Organization of cells into tissues, organs, and body structures

Question 20

Why is morphogenesis important?

Answer 20

It creates order and functional structures from differentiated cells

Question 21

What is growth?

Answer 21

Gradual increase in size or number of cells over time

Question 22

What are the two main types of growth in organisms?

Answer 22

Isometric growth and Allometric growth

Question 23

What is isometric growth?

Answer 23

Growth with shape preserved; all parts grow at same rate

Question 24

What is allometric growth?

Answer 24

Growth with shape change; parts grow at different rates

Question 25

Give an example of allometric growth.

Answer 25

Male fiddler crab’s enlarged claw

Question 26

What question addresses how cells form the next generation?

Answer 26

Reproduction

Question 27

What is reproduction?

Answer 27

Generation of new members of a species

Question 28

What is the ability of organisms to regrow lost parts called?

Answer 28

Regeneration

Question 29

Which animal is noted for perfectly regrowing limbs after amputation?

Answer 29

Mexican salamander

Question 30

What question examines how developmental changes create new anatomical structures?

Answer 30

Evolution

Question 31

What limits survivability of evolutionary mutations in embryos?

Answer 31

Embryogenesis restraints

Question 32

What concept shows similarities in vertebrate embryo plans?

Answer 32

Embryonic homologies

Question 33

How does the environment affect developing organisms?

Answer 33

Environmental integration

Question 34

What does environmental influence illustrate about development?

Answer 34

Interaction between genetic programming and external factors

Question 35

What is environmental integration in development?

Answer 35

Influence of physical and chemical environmental conditions on development

Question 36

What is the primary focus of Classic Embryology?

Answer 36

Observational biology and experimental manipulations

Question 37

What distinguishes modern developmental biology from classic embryology?

Answer 37

Use of molecular and genetic techniques

Question 38

Name one anatomical approach to studying embryology.

Answer 38

Comparative embryology or Evolutionary embryology

Question 39

What is comparative embryology?

Answer 39

Study of anatomical changes during development across organisms to identify evolutionary relationships

Question 40

What is evolutionary embryology?

Answer 40

Study of how developmental changes lead to evolution and how ancestry constrains development

Question 41

What does experimental embryology involve?

Answer 41

Manipulating developing organisms

Question 42

What do genetic approaches in developmental biology study?

Answer 42

Genetic control of development

Question 43

Who identified holoblastic and meroblastic cleavage patterns?

Answer 43

Aristotle

Question 44

What is holoblastic cleavage?

Answer 44

Entire egg divides into smaller cells (e.g., frogs, mammals)

Question 45

What is meroblastic cleavage?

Answer 45

Partial egg divides; yolk nourishes embryo (e.g., reptiles, birds)

Question 46

What is the study of birth defects called?

Answer 46

Teratology

Question 47

What causes genetic malformations and syndromes?

Answer 47

Genetic mutations

Question 48

What causes disruptions and teratogens?

Answer 48

External environmental agents

Question 49

What are disruptions in teratology?

Answer 49

Abnormalities caused by external agents

Question 50

What are teratogens?

Answer 50

Environmental agents causing developmental abnormalities

Question 51

What drug caused phocomelia as a teratogen example?

Answer 51

Thalidomide

Question 52

Why is human development rarely studied directly?

Answer 52

Ethical concerns, observational difficulty, no breeding for mutations

Question 53

Why are model organisms used in developmental biology research instead of humans?

Answer 53

Ethical/practical limits in humans; model organisms share fundamental developmental mechanisms

Question 54

Name three common model organisms used in developmental biology research.

Answer 54

Fruit flies, worms (C. elegans), zebrafish

Question 55

What plant is used as a model organism?

Answer 55

Arabidopsis thaliana

Question 56

Name a nematode model organism.

Answer 56

Caenorhabditis elegans

Question 57

What is the chicken's scientific name used in developmental studies?

Answer 57

Gallus gallus

Question 58

What is the zebrafish's scientific name?

Answer 58

Brachydanio rerio

Question 59

What is the hydra's scientific name used in research?

Answer 59

Hydra vulgaris

Question 60

What type of cells are used to study human development in vitro?

Answer 60

Human stem cells

Question 61

What is animal development and how does it begin?

Answer 61

Process starting from a fertilized egg (zygote) to adult organism

Question 62

What are the two main objectives of development?

Answer 62

Generate cellular diversity and complex structures; produce cells for next generation (continuity of life)