Chapters 43, 44, 45: The Internal Environment, Reproduction and Development Flashcards
1
Q
angiotensin II
A
Hormone that acts on the aldosterone-secreting cells of the adrenal cortex
2
Q
hypothalamus
A
Forebrain region that controls visceral activities (e.g., salt/water balance, core temperature, and reproduction); influences related behaviors (e.g., hunger, thirst, and sex) and emotional states (e.g., sweating with fear).
3
Q
urethra
A
Tube that conducts urine from the urinary bladder to an opening at the body’s surface.
4
Q
urinary system
A
Organ system that adjusts the volume and composition of blood, and so helps maintain extracellular fluid.
5
Q
distal tubule
A
Tubular portion of nephron closest to the collecting duct; selectively reabsorbs water and sodium.
6
Q
heterotherms
A
Organisms that sometime tightly control their core temperature, and sometimes allow it to shift
7
Q
proximal tubule
A
Nephron’s tubular portion into which water and solutes enter after being filtered from blood at bowman’s capsule.
8
Q
aldosterone
A
Adrenal cortex hormone; helps control sodium reabsorption.
9
Q
tubular reabsorption
A
In a kidney; diffusion or active transport of water and reclaimable solutes from a nephron into peritubular capillaries; under control of ADH and aldosterone.
10
Q
urinary excretion
A
mechanism by which excess water and solutes are removed from the body by way of a urinary system.
11
Q
vasoconstriction
A
Decrease in the diameter of an arteriole.
12
Q
Bowman’s capsule
A
Cup-shape portion of a nephron that receives water and solutes being filtered from blood.
13
Q
peritubular capillary
A
One of the set of blood capillaries around tubular parts of a nephron. Reabsorbs water and solutes, and secretes excess hydrogen ions and other substances.
14
Q
glomerular capillaries
A
Set of blood capillaries inside Bowman’s capsule of a nephron.
15
Q
peripheral vasoconstriction
A
Shrinking of the blood vessels in the skin.
16
Q
ectotherm
A
Animal that maintains core temperature mainly by gaining environmental heat; temperature regulation is mostly behavioral
17
Q
non shivering heat production
A
Hormonal response to prolonged or severe cold; elevates the rate of metabolism.
18
Q
shivering response
A
Rhythmic tremors of skeletal muscles in response to signals from the hypothalamus
19
Q
endotherm
A
Animal that maintains core temperature mainly by means of metabolic heat production.
20
Q
evaporation
A
The conversion of a substance from liquid state to gaseous state under input of heat energy.
21
Q
renal failure
A
Failure of kidneys to perform their regulatory and excretory function. Irreversible and fatal if untreated.
22
Q
glomerulus
A
First portion of the nephron, where water and solutes are filtered from blood.
23
Q
core temperature
A
Body’s internal temperature
24
Q
peripheral vasodilation
A
Expansion of the blood vessels in skin.
25
blood
Fluid connective tissue of water, solutes, and blood elements (blood cells and platelets). Blood transports substances to and from cells, and helps maintain internal environment.
26
convection
Transfer of heat by moving air or water.
27
pilomotor response
Creation of layer of still air next to the skin to reduce convective and radiative heat loss.
28
interstitial fluid
Of animals, the portion of extracellular fluid occupying the spaces between cells and tissues.
29
buffer system
A weak acid and the base that forms when it dissolves in water. The two work as a pair to counter slight shifts in pH.
30
extracellular fluid
Of most animals, all fluid not inside cells; plasma (blood's liquid portion) plus interstitial fluid (occupies spaces between cells and tissues).
31
evaporative heat loss
Heat loss across moist respiratory surfaces or the skin.
32
conduction
The gain or loss of heat as a result of contact with a solid object.
33
vasodilation
Increase in the diameter of an arteriole.
34
urea
Waste formed in the liver when two ammonia molecules combine with carbon dioxide.
35
urinary bladder
Distensible sac in which urine is stored before being excreted.
36
loop of Henle
Hairpin-shape, tubular region of a nephron that reabsorbs water and solutes.
37
antidiuretic hormone (ADH)
Hormone secreted by the hypothalamus, stored and released by the posterior ptuitary; makes tubule wall more permeable to water, resulting in a more concentrated urine.
38
filtration
First step in urine formation; pressure of heart contractions filters blood by forcing water and all solutes except proteins from glomerular capillaries into Bowman's capsule of nephron.
39
thirst center
Region in the hypothalamus that induces water-seeking behavior.
40
kidney
One of a pair of vertebrate organs that filter ions and other substances from blood; controls amounts returned to help maintain the volume and solute levels of extracellular fluid.
41
collecting duct
Duct that leads into the kidney's central cavity (renal pelvis).
42
acid-base balance
Maintenance of hydrogen ions within normal physiologic limits.
43
tubular secretion
Secretion by the cells of the tubular wall; excess hydrogen ions and a few other solutes are secreted into the nephron's lumen.
44
radiation
Gain of heat after exposure to radiant heat energy.
45
urine
Fluid of excess water, wastes, and solutes that forms in kidneys by filtration, reabsorption, and secretion.
46
nephron
One of the urine-forming tubules in a kidney; it filters water and solutes from blood, then selectively reabsorbs adjusted amounts of both in ways that help maintain the volume and composition of extracellular fluid.
47
ureter
One of a pair of tubes that conduct urine from the kidneys to the urinary bladder.
48
molting
Periodic shedding of body structures that are too small, worn out, or both. Permits certain animals to grow in size or renew some parts (e.g., exoskeletons, shells, hairs, feathers, and horns). Especially characteristic of insects and other arthropods.
49
pattern formation theory
Explanation of the orderly, sequential sculpting of embryonic cells into specialized animal tissues and organs. First cytoplasmic localization and, later, inductive interactions among classes of master genes are responsible. Gene products map out the basic body plan and create chemical gradients that dictate how specific body parts develop.
50
fate map
Surface diagram of certain early embryos (e.g., of Drosophila) showing where the differentiated cells of the adult originate.
51
gamete
Haploid cell, formed by meiotic cell division of a germ cell; required for sexual reproduction. Egg and sperm are examples.
52
cytoplasmic localization
Parceling of a portion of maternal messages in the egg cytoplasm to each blastomere that forms during cleavage.
53
gamete formation
Formation of sex cells (e.g., sperm and eggs); occurs in reproductive tissues or organs in most eukaryotic species.
54
gastrulation
Stage of animal development; major reorganization of new cells into two or three primary tissue layers.
55
viviparous
Giving birth to live young
56
mesoderm
Primary tissue layer important in evolution of all large, complex animals; gives rise to many internal organs and part of integument.
57
oviparous
Producing eggs that develop outside the mother's body.
58
apoptosis
Programmed cell death. Molecular signals activate weapons of self-destruction in body cells that finished their prescribed functions or became altered; as by infection or cancerous transformation.
59
yolk
Protein-rich, lipid-rich substance that nourishes embryonic stages.
60
aging
Of any multicelled organism showing extensive cell differentiation, a gradual and expected deterioration of the body over time.
61
endoderm
Inner primary tissue layer of an animal embryo; source of inner gut lining and derived organs.
62
cleavage
Early stage of animal development. Mitotic cell divisions divide a fertilized egg into many smaller nucleated cells; original volume of egg cytoplasm does not increase.
63
embryo
Of animals, a multicelled body that is formed by cleavage, gastrulation, and other early developmental events.
64
sexual reproduction
Production of offspring by way of meiosis, gamete formation, and fertilization.
65
ectoderm
The first-formed, outermost primary tissue layer of animal embryos; gives rise to nervous system tissues and integument's outer layer.
66
blastomere
One of the small, nucleated cells that forms during cleavage.
67
ovoviviparous
Fertilized eggs develop inside the mother, then offspring are born live. Yolk reserves, not the mother's tissues, sustain the eggs.
68
cell differentiation
Key process of development. Different cell lineages become specialized in their composition, structure, and function by activating and suppressing some fraction of the genome in different ways.
69
neural tube
Embryonic and evolutionary forerunner of brain and spinal cord.
70
organ formation
Developmental stage in which primary tissue layers give rise to cell lineages unique in structure and function. Descendants of those lineages give rise to all the different tissues and organs of the adult.
71
pattern formation
Emergence of specialized cells and organs in an ordered spatial pattern.
72
internal fertilization
Union of sperm and egg inside the body of the female.
73
fertilization
Fusion of a sperm nucleus with the nucleus of an egg, which thus becomes a zygote.
74
morphogenesis
Genetically prescribed program of orderly changes in the size, shape, an proportions of an animal embryo, leading to specialized tissues and early organs.
75
AER
Population of cells that forms in the developing limbs of mammals and birds.
76
sperm
Mature male gamete.
77
growth and tissue specialization
Final stage of animal development doing which organs increase in size, and gradually assume specialized functions.
78
gray crescent
Area of pigmentation that forms after fertilization of a frog egg; establishes the anterior-posterior axis for the body
79
embryonic induction
In a growing embryo, one tissue releases a gene product that changes the developmental fate of an adjacent tissue.
80
metamorphosis
Major changes in body form during the transition from the embryo to the adult; involves hormonally controlled size increases, reorganization of tissues, and remodeling of body parts.
81
cleavage furrow
Ringlike depression defining cleavage plain for dividing animal cells.
82
juvenile
Of some animals, a post-embryonic stage that changes only in size and proportion to become the adult (no metamorphosis).
83
homeotic gene
A master gene governing the development of specific body parts.
84
zygote
First cell of a new individual, formed by fusion of a sperm nucleus with egg nucleus at fertilization; a fertilized egg
85
blastocyst
Type of blastula; blastomeres form a surface layer, a cavity filled with their own secretions, and an inner cell mass.
86
blastula
An early outcome of cleavage; some number of blastomeres enclosing a fluid-filled cavity.
87
oocyte
Immature egg of all animals and some protistans.
88
asexual reproduction
Any of a number of modes of reproduction by which offspring arise from a single parent and inherit the genes of that parent only.
89
telomeres
Repetitive DNA sequences that cap the ends of chromosomes.
90
embryonic induction
In a growing embryo, release of a gene product from one tissue that affects the developmental fate of an adjacent tissue.
91
morphogen
Degradable molecule that diffuses from an embryonic signaling center into adjoining tissues. The concentration gradient helps cells assess their position in the body, and it influences their differentiation.
92
ovary
In most animals, a female gonad. In flowering plants, the enlarged base of one or more carpels. A fruit is a mature ovary often combined with other flower parts.
93
blastocyst
Type of blastula; blastomeres form a surface layer, a cavity filled with their own secretions, and an inner cell mass.
94
somite
One of many paired segments inside a vertebrate embryo that gives rise to most bones, skeletal muscles of the head and trunk, and the overlying dermis
95
implantation
Process of pregnancy. A blastocyst burrows into the endometrium and establishes connections by which the mother will exchange substances with the embryo (and fetus) that develops from the blastocyst's inner cell mass.
96
vas deferens
One of the paired ducts that transports sperm from the epididymis to the urethra.
97
progesterone
Female sex hormone secreted by the ovaries and the corpus leuteum. During the menstrual cycle, concentration peaks during the luteal phase.
98
ovum
Mature secondary oocyte, mature egg
99
teratogen
Chemical or environmental factor that may induce deformities in the embryo or fetus.
100
gastrulation
Stage of animal development; major reorganization of new cells into two or three primary tissue layers.
101
fertilization
Fusion of a sperm nucleus with an egg nucleus to form a zygote.
102
ovulation
Release of a secondary oocyte from an ovary during one menstrual cycle. .
103
amnion
Extraembryonic membrane; boundary layer of a fluid-filled sac in which some vertebrate embryos grow and develop, move freely, and remain protected from impacts and temperature shifts.
104
oocyte
Immature egg of all animals and some protistans.
105
primary oocyte
An immature egg that is arrested in meiosis I.
106
follicle
A mammalian oocyte with its surrounding layer of cells.
107
luteal phase
Portion of the menstrual cycle during which the corpus luteum forms and secretes progesterone.
108
endometrium
Innermost lining of uterus
109
testosterone
Sex hormone with roles in the development and functioning of the vertebrate male reproductive system; secreted by the Leydig cells of the testes.
110
inhibin
Hormone that is secreted by Sertoli cells and acts to inhibit secretion of GnRH and LH
111
secondary oocyte
Egg cell produced by completion of meiosis I and cytoplasmic division of a primary oocyte. It is arrested in meiosis II.
112
chorion
Type of extraembryonic membrane that becomes part of placenta. Villi (absorptive structures) form at its surface and facilitate exchanges of substances between the embryo and mother.
113
in vitro fertilization
Fertilization in a test tube.
114
seminiferous tubules
The highly coiled tubules within the testes that produce sperm.
115
sexually transmitted disease (STD)
Disease caused by infection of certain pathogens after sexual intercourse.
116
GnRH
Releasing hormone that is produced by the hypothalamus and stimulates release of FSH and LH by the anterior ptuitary.
117
sperm
Mature male gamete.
118
follicle-stimulating hormone (FSH)
An anterior ptuitary hormone that stimulates follicle development and secretion of estrogen in females and stimulates sperm production in males.
119
cell differentiation
Key process of development. Different cell lineages become specialized in their composition, structure, and function by activating and suppressing some fraction of the genome in different ways.
120
vagina
The part of the female reproductive system that receives sperm, forms part of the birth canal, and channels menstrual flow to the exterior.
121
coitus
Sexual intercourse
122
lactation
Milk production by hormone-primed mammary glands.
123
allentois
An extraembryonic membrane. Functions in respiration and in storing metabolic wastes of embryos of reptiles, birds, and certain mammals. In humans, the urinary bladder and placental blood vessels from from it.
124
prolactin
Hormone secreted by the anterior ptuitary that induces the synthesis of enzymes necessary for milk production.
125
morphogenesis
Genetically prescribed program of orderly changes in the size, shape, and proportions of an early embryo, leading to specialized tissues and early organs.
126
uterus
Of a female placental mammal, a muscular, pear-shape organ in which the embryo is contained and nurtured during pregnancy.
127
Sertoli cells
Cells in the seminiferous tubules that provide the forerunners of sperm with nourishment and molecular signals.
128
polar body
One of four cells that form by the meiotic cell division of an oocyte but that does not become the ovum.
129
semen
Sperm-bearing fluid expelled from the penis during orgasm.
130
follicular phase
Portion of the menstrual cycle during which menstruation occurs, and a follicle matures in the ovary.
131
corpus luteum
Glandular structure; forms from cells of ruptured ovarian follicle and secretes progesterone and estrogen.
132
labor
Dilation of the cervix and expulsion of the fetus from the uterus by muscular contractions.
133
human chorionic gonadotropin (HCG)
Hormone secreted by the developing placenta that helps maintain endometrium during the first trimester of pregnancy.
134
testes (singular, testis)
Gonad of some male animals; a primary reproductive organ in which male gametes and sex hormones are produced.
135
menstrual cycle
Recurring cycle, lasting twenty-eight days on average in adult human females; a secondary oocyte is released from an ovary and the endometrium becomes primed to receive it.
136
secondary sexual trait
A trait associated with maleness or femaleness, but with no direct role in reproduction (e.g., the distribution of body hair and body fat).
137
yolk sac
An extraembryonic membrane. In most shelled eggs, it holds nutritive yolk; in humans, part of the yolk sac becomes a site of blood cell formation and some cells give ride to forerunners of gametes.
138
corticotropin releasing hormone (CRH)
Hormone that stimulates release of corticotropin; secreted by the hypothalamus and, during pregnancy, by the placenta
139
Leydig cells
Testosterone-secreting cells that lie between the seminiferous tubules of the testes
140
Fetus
Developing human from the ninth week until birth
141
menstruation
Sloughing of a blood-enriched endometrium when pregnancy does not occur.
142
gonad
Primary reproductive organ in which animal gametes are produced.
143
zona pellucida
Glycoprotein-rich layer that covers the secondary oocyte
144
cervix
The lower part of the uterus that connects it with the vagina
145
oxytocin
A hypothalamic hormone that is stored in the posterior ptuitary and stimulates uterine contraction and milk production
146
placenta
Blood-engorged organ composed of some endometrial tissue and extraembryonic membranes in pregnant female placental mammals. Allows exchanges between the mother and fetus without an intermingling of their bloodstreams, thus sustaining the new individual and allowing its blood vessels to develop apart from the mother's
147
abortion
Premature, spontaneous or induced expulsion of the embryo or fetus from uterus. Spontaneous abortion also called miscarriage
148
estrogen
Female sex hormone that helps oocytes mature. Induces changes in the uterine lining during menstrual cycle and pregnancy, helps maintain secondary sexual traits, and influences growth and development. During the menstrual cycle, concentration peaks just before ovulation
149
somite
One of many paired segments in a vertebrate embryo that give rise to most bones, skeletal muscles of head and trunk, and dermis.
150
luteinizing hormone (LH)
An anterior ptuitary hormone that stimulates ovulation, luteinization, and secretion of estrogen in females and stimulates testosterone secretion in males.
151
urethra
Tube that conducts urine from the urinary bladder to an opening at body surface and, in males, carries sperm from the ejaculatory duct to the body surface.
152
puberty
Period during which reproductive organs and structures start maturing.
