Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
MCAT Bio. Ch. 3
| Term | Definition |
|---|---|
| Fertilization | Joining of a sperm and an ovum, which occurs in the ampulla of the fallopian tube. |
| Once A Sperm Contacts The Oocyte's Plasma Membrane, The Sperm Establishes: | The acrosomal apparatus and injects its nucleus |
| Cortical Reaction / When The First Sperm Penetrates, It Releases: | Calcium ions which prevents additional sperm from fertilizing the egg and increases the metabolic rate of the resulting diploid zygote. |
| Fraternal Dizygotic Twins Result From: | The fertilization of two eggs by two different sperm. |
| Identical Monozygotic Twins Result From: | Splitting of a zygote in two. |
| Cleavage Is Defined As: | Early divisions of cells in the embryo |
| Indeterminate Cleavage Results In: | Cells that are capable of becoming any cell in the organism |
| Determinate Cleavage: | Results in cells that are committed to differentiating into a specific cell type |
| Morula | Solid mass of cells seen in early development |
| Blastula (Blastocyst) | Have a fluid-filled center called a blastocoel and has two different cell types including trophoblasts which become placental structures, and the inner cell mass which becomes the developing organism |
| The Blastula Implants In The: | Endometrial lining and forms the placenta |
| Chorion Contains: | Chorionic villi which penetrate the endometrium and create the interface between maternal and fetal blood |
| Allantois Is Involved In: | Early fluid exchange between the embryo and the yolk sac |
| Amnion Lies Just Inside The: | Chorion and produces amniotic fluid |
| Developing Organism Is Connected To The Placenta Via The: | Umbilical cord |
| During Gastrulation, The Archenteron Is Form With: | A blastopore at the end |
| Ectoderm (Primary Germ Layers) | Becomes epidermis, hair, nails, and the epithelia of the nose, mouth, and anal canal as well as the nervous system (adrenal medulla) and lens of the eye |
| Mesoderm (Primary Germ Layers) | Becomes much of the musculoskeletal, circulatory, and excretory systems |
| Endoderm (Primary Germ Layers) | Becomes much of the epithelial linings of the respiratory and digestive tracts, and parts of the pancreas, thyroid, bladder, and distal urinary tracts |
| Neurulation | Development of the nervous system that begins after the formation of the three germ layers |
| Notochord Induces A Group Of: | Overlying ectodermal cells to form neural folds surrounding a neural groove |
| Neural Crest Cells Become: | The peripheral nervous system (sensory ganglia, autonomic ganglia, adrenal medulla, and Schwann cells) and other specific cell types (calcitonin-producing cells of thyroid, melanocytes in skin) |
| Teratogens | Substances that interfere with development which cause defects or even death of the developing embryo |
| Determination | Commitment to a specific cell lineage which can be accomplished by uneven segregation of cellular material during mitosis |
| Morphogens | Promote development down a specific cell line. In order for this to occur, a cell must have competency. |
| Differentiation Refers To: | The changes that a cell undergoes due to select transcription to take on characteristics appropriate to its cell line |
| Totipotent Cells | Cells that are able to differentiate into all cell types including the three germ layers and placental structures |
| Pluripotent Cells | Cells that are able to differentiate into all three of the germ layers and their derivatives |
| Multipotent Cells | Cells that are able to differentiate only into a specific subset of cell types |
| Inducer | Releases factors to promote the differentiation of a competent responder |
| Autocrine Signals Act On: | The same cell that released the signal |
| Paracrine Signals Act On: | Cells in the local area |
| Juxtacrine Signals Act Through: | Direct stimulation of the adjacent cells |
| Endocrine Signals Act On: | Distant tissues after traveling through the bloodstream |
| Growth Factors | Peptides that promote differentiation and mitosis in certain tissues |
| If Two Tissues Both Induce Further Differentiation In Each Other, This Is Termed: | Reciprocal induction |
| Apoptosis | Programmed cell death via the formation of apoptotic blebs that are absorbed and digested by other cells |
| Regenerative Capacity | Ability of an organism to regrow certain parts of the body |
| Fetal Hemoglobin (HbF) Has a Higher Affinity For: | Oxygen than adult hemoglobin (primarily HbA) which assists in the transfer and retention of oxygen in the fetal circulatory system. |
| Placental Barrier Serves As: | Immune protection against pathogens and allows for the transfer of antibodies from mother to child |
| Placenta Serves Endocrine Functions Such As: | Secreting estrogen, progesterone, and human chorionic gonadotropin (hCG) |
| Umbilical Arteries Carry: | Deoxygenated blood from teh fetus to the placenta |
| Umbillical Vein Carries: | Oxygenated blood from the placenta back to the fetus |
| Foramen Ovale Connects (Fetal Circulatory System): | The right atrium to the left atrium, bypassing the lungs. |
| Ductus Arteriosus (Fetal Circulatory System) | Connects the pulmonary artery to the aorta, bypassing the lungs |
| Ductus Venosus (Fetal Circulatory System) | Connects the umbilical vein to the inferior vena cava, bypassing the liver |
| First Trimester (Gestation And Birth) | Organogenesis occurs aka the development of heart, eyes, gonads, limbs, liver, brain |
| Second Trimester (Gestation And Birth) | Tremendous growth occurs, movement begins, the face becomes distinctly human, and the digits elongate |
| Third Trimester (Gestation And Birth) | Rapid growth and brain development continue. Then, there is a transfer of antibodies to the fetus. |
| Birth (Gestation And Birth) | Cervix thins out and the amniotic sac ruptures. The uterine contractions occur, and are coordinated by prostaglandins and oxytocin which results in the birth of the fetus. The placenta and umbilical cord are expelled. |
Created by:
SamB91
Popular MCAT sets