ANSC 301 EXAM 3 questions and
answers already passed
Will animals that are not fed well reproduce optimally or at all? - correct answer ✔✔NO--> only
healthy animals reproduce; optimum reproduction requires optimum nutrition
What is required before an animal will become fertile? - correct answer ✔✔requires sufficient
body weight and energy reserves
*lactation is most energetically demanding stage*
What predicts age at puberty? - correct answer ✔✔1. body growth 2. increase in fat reserves
BODY FAT SET POINT
Well fed animals grow faster and reach puberty earlier
What hormone signals energy status that allows reproductive cycles to start? - correct answer
✔✔LEPTIN
coming from adipose tissue, telling the body how much energy it has
What hormones does increased leptin change in the brain? - correct answer ✔✔increased
GnRH (which then affects LH and FSH)
How does this control population size in wild rodents? - correct answer ✔✔cycles (of fertility/
infertility) based of nutrient/food availability
,Why would there generally be a negative relationship between fertility and milk production in
dairy cows? - correct answer ✔✔they were not selecting for fertility
high producing cows in early lactation have neg energy balance (i.e. they lose weight)
delay estrous (fertility) until put weight back on (FED WEEL)
What maternal tissues contribute to the requirement for pregnancy? - correct answer ✔✔1.
uterus & placenta, fetus
2. mammary requirement
What two factors are important to know to determine the impact of a pregnancy on the
mother/dam? - correct answer ✔✔ratio fetal weight/maternal weight
gestational length
in mice: LARGE burden, short gestation
in elephants: small burden, long gestation
What period of gestation are nutrient requirements the highest? Why? - correct answer ✔✔last
trimester (GROWTH OF FETUS)
lactation
Is under or over-feeding an issue in early pregnancy? - correct answer ✔✔BOTH ; can cause
embryo mortality
feed at or a little above maintenance for a month after breeding
, Why do we not want to over feed during late gestation? - correct answer ✔✔synthesize and
deposit fat very efficiently with progesterone
If an animal is underfed during late gestation who gets higher priority for the nutrients- mom or
fetus? - correct answer ✔✔prioritize FETUS
What is fetal programming and the "Barker Hypothesis"? What is the biological explanation? -
correct answer ✔✔in utero undernutrition:
-decreases weight, increases age at first conception, and decreases litter size
-high fat diet in male rats increased insulin resistance in adult offspring
biological explanation: epigenetics
Nutritional Epigenetics - correct answer ✔✔impact DNA methylation through Maternal Diet
Supplementation
--> impacts generations to come
GROWTH - correct answer ✔✔
What is a key tissue that helps keep young animals warm?
How is the mitochondria and the electron transport chain involved?
Is this mechanism present in adults? - correct answer ✔✔Brown Adipose Tissue (in kidneys and
neck) regulates thermoneutral zone-->
ABUNDANT MITOCHONDRIA and thus ETC w/
"uncoupling protein 1"--> HEAT
utilizes own fatty acids
answers already passed
Will animals that are not fed well reproduce optimally or at all? - correct answer ✔✔NO--> only
healthy animals reproduce; optimum reproduction requires optimum nutrition
What is required before an animal will become fertile? - correct answer ✔✔requires sufficient
body weight and energy reserves
*lactation is most energetically demanding stage*
What predicts age at puberty? - correct answer ✔✔1. body growth 2. increase in fat reserves
BODY FAT SET POINT
Well fed animals grow faster and reach puberty earlier
What hormone signals energy status that allows reproductive cycles to start? - correct answer
✔✔LEPTIN
coming from adipose tissue, telling the body how much energy it has
What hormones does increased leptin change in the brain? - correct answer ✔✔increased
GnRH (which then affects LH and FSH)
How does this control population size in wild rodents? - correct answer ✔✔cycles (of fertility/
infertility) based of nutrient/food availability
,Why would there generally be a negative relationship between fertility and milk production in
dairy cows? - correct answer ✔✔they were not selecting for fertility
high producing cows in early lactation have neg energy balance (i.e. they lose weight)
delay estrous (fertility) until put weight back on (FED WEEL)
What maternal tissues contribute to the requirement for pregnancy? - correct answer ✔✔1.
uterus & placenta, fetus
2. mammary requirement
What two factors are important to know to determine the impact of a pregnancy on the
mother/dam? - correct answer ✔✔ratio fetal weight/maternal weight
gestational length
in mice: LARGE burden, short gestation
in elephants: small burden, long gestation
What period of gestation are nutrient requirements the highest? Why? - correct answer ✔✔last
trimester (GROWTH OF FETUS)
lactation
Is under or over-feeding an issue in early pregnancy? - correct answer ✔✔BOTH ; can cause
embryo mortality
feed at or a little above maintenance for a month after breeding
, Why do we not want to over feed during late gestation? - correct answer ✔✔synthesize and
deposit fat very efficiently with progesterone
If an animal is underfed during late gestation who gets higher priority for the nutrients- mom or
fetus? - correct answer ✔✔prioritize FETUS
What is fetal programming and the "Barker Hypothesis"? What is the biological explanation? -
correct answer ✔✔in utero undernutrition:
-decreases weight, increases age at first conception, and decreases litter size
-high fat diet in male rats increased insulin resistance in adult offspring
biological explanation: epigenetics
Nutritional Epigenetics - correct answer ✔✔impact DNA methylation through Maternal Diet
Supplementation
--> impacts generations to come
GROWTH - correct answer ✔✔
What is a key tissue that helps keep young animals warm?
How is the mitochondria and the electron transport chain involved?
Is this mechanism present in adults? - correct answer ✔✔Brown Adipose Tissue (in kidneys and
neck) regulates thermoneutral zone-->
ABUNDANT MITOCHONDRIA and thus ETC w/
"uncoupling protein 1"--> HEAT
utilizes own fatty acids
