Exam 2 Review

Question 1

Allen’s rule

Answer 1

The principle that an animals limb lengths are heat-related; limbs are longer in hot environments and shorter in cold environments.

Question 2

Bergmanns rule

Answer 2

The principle that an animals size is heat related; smaller bodies are adopted to hot environments and larger bodies are adapted to cold environments

Question 3

BMR

Answer 3

The rate at which an organisms body while at rest, expends energy to maintain basic bodily functions; measured by the amount of heat given off per kg of body weight

Question 4

Clines

Answer 4

A gradual change in some phenotypic characteristic from one population to the next.

Question 5

Functional adaptations

Answer 5

Biological changes that occur during an individuals lifetime,increasing the individuals fitness in a given environment

Question 6

Hypoxia

Answer 6

Less than usual sea-level amount of oxygen in the air or in the body

Question 7

Homeostasis

Answer 7

The maintenance of the internal environment of an organism within an acceptable range.

Question 8

Life history

Answer 8

The timing and details of growth events and development events such as conception through senescence and death

Question 9

Adolescence

Answer 9

Is marked by profound biological changes. Sexual maturation commences with puberty; bigger breast and menstruation in girls; voices deepen in boys; sexual dimorphism in no sexes

Question 10

Melanin

Answer 10

Brown pigment that determines the darkness or lightness of a humans skin color due to its concentration in the skin.

Question 11

With ongoing exposure to UV radiation, the melanocytes increase the number and size of _______ granules.

Answer 11

Melanin

Question 12

Melanocytes

Answer 12

Melanin producing cells located in the skins epidermis.

Question 13

UVR

Answer 13

It is a component of solar radiation. It is the best predictor of skin color. Darkest skin is associated with highest UV radiation. Individuals living in low latitudes or equatorial regions of the globe have some of the darkest skin due to more prolonged UV radiation. As latitude increases the UV radiation decreases and so does the amount of melanin in the skin; therefore the lightest are in higher latitudes.

Question 14

Folate

Answer 14

Essential for the synthesis and repair of DNA and therefore directly affects cell division and homeostatis. Very tiny deficiencies of folate have been linked to a range of health issues, neural tube, Cleft palate, pregnancy loss, reduced sperm production. Folate levels decline when exposure to high and prolonged levels of UV radiation. However, skin color and melanin production are key elements in protecting the body from folate depletion.

Question 15

Menarche

Answer 15

Refers to the onset of menstruation in an adolescence female

Question 16

Secular trends

Answer 16

A phenotypic change due to multiple factors. Such trends can be positive (increased height) or negative (decreased height)

Question 17

Vasoconstriction

Answer 17

The decrease in blood vessels diameter due to the action of a nerve or of a drug; also can occur as a response to cold temperature. The human body’s first response to cold stress is vasoconstriction. Decreasing the diameter of the blood vessels reduces blood flow and heat loss, from body’s core to the skin. Shivering is chief mechanism for producing heat.

Question 18

Wolff’s law

Answer 18

Lays out the homeostatic balance of osteoblastic and osteoblastic activity, in which bone mass is produced where it is needed and taken away where it isn’t needed. It also accounts for the remodeling of bone that occurs during life, the changing of certain bones shape as he result of particular activities.

Question 19

Growth velocity

Answer 19

Each of the five postnatal periods has a different growth velocity, rate of growth per year. During infancy, the period of most rapid growth, the deciduous dentition erupts through the gums. During childhood, general growth levels off, but the still rapidly growing brain requires the child to have a diet rich in fats, protein, and energy. During the juvenile years, growth slows. Adolescence presents a number of biological developments such as menarche and sexual dimorphism

Question 20

Life stages

Answer 20

Prenatal stage- which includes 3 trimesters of pregnancy and ends with birth. Postnatal stage- includes neonatal stage (first month), infancy (second month to end of lactation, usually by end of third year) childhood (3-7) juvenile period (7-10 girls 7-12 boys) puberty (days or weeks) adolescence (5-10 years after puberty). Adult stage- includes the reproductive period and senescence

Question 21

Senescence

Answer 21

Refers to an organisms biological changes in later adulthood. Senescence, which accompanies aging, is a biological process that is characterized by a reduction in homeostasis, the body’s ability to keep its organs and its physiological systems stable in the face of environmental stress. Senescing persons are increasingly susceptible to stress and death and have a decrease capacity to reproduce.

Question 22

Homeothermic

Answer 22

Refers to an organisms ability to maintain a constant body temperature despite great variations in environmental temperature. A constant core temperature is essential for normal physiology, including brain function, limb function, and general body mobility. Humans can tolerate 98.6 F but 104-107 F is bad.

Question 23

Macronutrients

Answer 23

Essential chemicals nutrients, including fat, carbohydrates, and protein, that a body needs to live and to function normally. The total daily expenditure consists of basal metabolic requirement plus all the other energy requirements, and we fulfill all these energies by consuming specific macronutrients and micronutrients

Question 24

Nutritional adaptations

Answer 24

Primates not only have to adapt to climate but they also adapt to diet. This adaptation is crucial to acquiring the necessary energy and nutrients for reproduction, growth, and development. Each body function requires a certain amount of energy and particular nutrients, and a lack of energy or of nutrients can hamper body functions.

Question 25

Climate adaptations

Answer 25

Humans are homeothermic- maintain constant body temperature. The initial physiological response to heat is vasodilation, expansion of blood vessels near body’s surface. Move blood away from body’s core to surface; sweating evolved as a thermoregulatory adaption in association with the general loss of body hair. Bergmanns and Allen’s rule; body shape is a genetic adaptation. Vasoconstriction- constriction of blood vessel; reduction in blood flow and heat loss. Shivering produces heat. One of the most profound environmental factors that humans deal with daily is solar radiation- plays a role in evolution and development of skin color. UV radiation exposure affects melanocytes production of size and quantity of melanin granules. Higher latitudes have less UV radiation thus lighter skin. Melanin acts as sunscreen so lighter people will get burnt easier. You need sun exposure- vitamin D; folate is important in development of cells. You need a moderate amount of sun exposure.

Question 26

Primates

Answer 26

A group of mammals in the order primates that have complex behavior, varied forms of locomotion, and a unique set of traits, including larger brains, forward facing eyes, fingernails, and a reduced snout. Primates are arboreally adapted- physical traits that enable an organism to live in trees. Dietary plasticity- diets flexibility in adapting to a given environment. Parental investment- time and energy parents expend for their offsprings benefit.

Question 27

Prosimians

Answer 27

Suborder of primates; called lower or lesser primates; most primitive primates, retaining a number or primitive characteristics: characteristics present in multiple species of a group, such as rhinarium and tend to have specialized diets and behaviors than anthropoids. They do have derived characteristics- such as lemurs tooth comb. Example: prosimians, lorises, galagos, tarsiers, and lemurs.

Question 28

Anthropoids

Answer 28

Suborder or primates; higher primates- monkeys old and new, apes, humans. Have larger brains, more sexually dimorphic, fewer teeth, convergent eyes, and enclosed by a continuous ring of bone, and see in color.

Question 29

Platyrrhines

Answer 29

New world monkeys, have nostrils that re round and separated by a wide nasal strip.

Question 30

Catarrhines

Answer 30

Old world monkeys; nostrils are close together and point downward.

Question 31

Primate locomotion

Answer 31

Brachiators-organisms that move by arm-swinging. Quadrupedalism- walk on 4 limbs; knuckle-walking- chimps and gorillas walk on knuckles, fist-walking- orangutans walks palms which are enclosed in fists. Suspensory apes- great and lesser apes, forearms longer than hindlimbs

Question 32

Dental formula

Answer 32

The numerical description of a species teeth, listing the number, in one quadrant of the jaws, of incisors, canines, premolars, and molars. Dental formula is very useful in studies of ancestral primate species.

Question 33

Honing complex

Answer 33

The dental form in which the upper canines are sharpened against the lower third premolars when the jaw opened and closed. In old world monkeys and apes, the canines are part of a canine-premolar honing complex, in which the upper canine fits in a space, or diastema, between the lower canine and lower third premolar. This configuration slices food, especially leaves and other plants.

Question 34

Y-5

Answer 34

Hominids pattern of lower molar cusps; apes and humans have slower molar with 5 separate cusps that are separated by grooves. This called y-5 molar. Apes and humans upper molars generally have 4 cusps, separated by grooves.

Question 35

Diastema

Answer 35

A space between two teeth; between the lower canine and lower third premolar

Question 36

Diurnal

Answer 36

Refers to those organisms that normally are awake and active during daylight hours; color vision in primates shifted from nocturnal adaptation to a diurnal adaptation.

Question 37

Nocturnal

Answer 37

Most prosimians are nocturnal

Question 38

Prehensile tail

Answer 38

Gal that acts as a kind of hand for support in trees, common on new world monkeys.

Question 39

Opposable thumbs

Answer 39

Refers to primates thumb, in that it can touch each of the four fingertips, enabling a grasping ability; power and precision grip.

Question 40

K-selected

Answer 40

Describes primates that have a small litter and spend a lot of time teaching that baby; wait a long time to have another baby. R-selected species are like dogs; have big litters and don’t nurture the child for a very long time.

Question 41

Rhinarium

Answer 41

Naked surface around the nostrils, typically wet in mammals. Most higher primates have lost the rhinarium and the long snout; some of the prosimians, the more primitive primates, such as lemurs, lorises have retained the rhinarium, and they continue to rely on we’ll developed sense of smell.

Question 42

Preadaptation

Answer 42

An organisms use of an anatomical feature in a way unrelated to the features original function;the vertical tendency in a prehuman ancestor was an essential preadaptation to humans bipedality.

Question 43

Tooth comb

Answer 43

Anterior teeth (incisors and canines) that have been tilted forward creating a scraper. Prosimians lower incisors and canines are elongated, crowded together, and projecting forward. This specialized feature, a tooth comb, is especially useful for extracting resins from trees.

Question 44

Bilophodont

Answer 44

Refers to lower molars, in old world monkeys, that have two ridges. Each pair of cusps, front and back, is connected by an enamel ridge, or loph. This is called a bilophodont (2 ridge molar) molar.

Question 45

Lemurs

Answer 45

Are prosimians and only found in Madagascar, make up 21% of primate genera worldwide. Lorises and lemurs have primitive dentitions- some have 36 teeth, and teeth comb.