Mammal Anatomy Quiz

Mammal Anatomy

• Tissues are composed of cells with a similar structure and function
• Similar cells form tissues
• Organs are made up of tissues
• Organs are part of organ systems (e.g., nervous/digestive)
• Epithelial tissue is arranged in continuous sheets of closely packed cells
• It covers external body surfaces and lines body cavities
• Connective tissue connects organs, protects, supports, fills spaces, produces blood cells, and stores fat
• The cells are usually surrounded by a matrix of acellular material
• Connective tissue includes cartilage, bone, blood, fat, and other tissues
• Muscular tissue is composed of long cells called muscle fibers
• It consists mostly of proteins and includes skeletal, cardiac, and smooth muscle
• Nervous tissue consists of neurons and glial cells
• Glial cells have many support and service functions

Mammal Anatomy Postures

• Plantigrade: entire foot on the ground (e.g., humans)
• Digitigrade: up on the digits (e.g., cats, dogs)
• Unguligrade: on the tips of toes with hoofs (e.g., ungulates like horses, donkeys)

Mammal Anatomy Antlers and Horns

• Antlers: branched, shed every year, usually found in male deer, elk, and moose
• Horns: not branched, permanent, consist of a keratin sheath over bone, found in both sexes of some animals, rhinoceros horns are composed of hair-like keratinized filaments, and skin-covered bone ossicones are found in giraffes.

Mammal Anatomy Hair

• Hair is a key feature of mammals
• It grows out of hair follicles and is composed of a tough protein called keratin

Mammal Anatomy Glands

• Sweat glands are only found in mammals, with two types: eccrine and apocrine
• Eccrine glands secrete watery sweat for evaporative cooling
• Apocrine glands secrete a white or yellow sweat at puberty, primarily in armpits, pubic areas, breasts
• Scent glands are present in most mammals and used to attract mates, mark territories, communicate, and warn others (e.g., skunks)
• Sebaceous glands secrete sebum, oils the skin and hair, and keeps them pliable. Has antibacterial properties, and most are associated with hair follicles.
• Mammary glands produce milk and are unique to mammals, probably modified sweat glands

Mammal Ecology

• Environment: everything an organism is exposed to( abiotic components: weather, light, nutrients, and water; biotic components: all the organisms that live in an organism's environment)
• Population: members of a specific species in an area
• Community: all populations in a particular area
• Ecosystem: the abiotic and biotic factors in an area
• Biosphere: global ecosystem
• Abiotic factors: temperature, water, sunlight, wind, rocks, soil, periodic disturbances
• Biomes: aquatic (oceans, wetlands, estuaries- cover 75% of Earth's surface) and terrestrial biomes (temperate deciduous forests cover 25% of Earth's surface)

Mammal Ecology Density and Dispersion

• Density: number of individuals per unit area
• Dispersion: pattern of spacing of individuals in a population
• Factors influencing population growth:
• Intraspecific competition: competition within species
• Density-dependent factors: competition for resources increases with population density
• Density-independent factors: weather, natural disasters
• Patterns of dispersion:
• Clumped
• Uniform
• Random
• Carrying capacity: maximum stable population an environment can support
• Species diversity includes species richness (number of species) and relative abundance (proportion of each species)

Mammal Ecology Stability and Disturbances

• Stability: constant state (equilibrium) a community may reach
• Disturbances: have major effects on communities
• Ecological succession: replacement of species over time (primary succession begins in lifeless areas like volcanic islands; secondary succession begins after a disturbance such as forestry)
• Biogeography: study of the distribution of species and communities
• Trophic levels: different feeding levels in an ecosystem
• Primary producers: base trophic level, support other levels, usually photosynthetic organisms (plants, phytoplankton)
• Primary consumers: herbivores that eat primary producers
• Secondary consumers: carnivores that eat primary consumers Food chains and webs form from trophic levels.

Mammal Ecology Behavioral Ecology

• Proximate causes of behavior: how questions about behavior (e.g., how bats use sonar)
• Ultimate causes of behavior: why questions about behavior's evolutionary basis (e.g., why do birds migrate?)
• Fitness: ability of individuals to reproduce and have offspring that survive
• Primates: mostly arboreal (tree dwelling), grasping hands, flexible limbs, well-developed brains, binocular vision.
• Two groups of primates (Traditional): prosimians (lemurs, tarsiers) and simians (monkeys, apes).

Mammal Ecology Primates

• New world monkeys: found in South America, many have prehensile tails
• Old world monkeys: found in Africa and Asia, lack prehensile tails
• Apes: first appear in fossil record 22 million years ago, generally no tails, longer arms than monkeys, proportionally larger brains.
• Gibbons/siamangs: small, social, noisy primates that move by brachiation, found in SE Asia, endangered
• Orangutans: large, red, arboreal apes in SE Asia
• Great apes: include orangutans, chimpanzees, gorillas, bonobos; all are endangered

Mammal Ecology Human Evolution

• Humans belong to the group of primates called hominins.
• Upright bipedal posture freed up hands
• Upright posture also important for predator vision
• Ahelanthropus Tchadenis: oldest known hominin
• Ardipithecus Ramidus: bipedal hominin
• Early hominins: sahelanthropus, ardipithecus, orrorin (some may not be considered true hominins)

Test your knowledge of mammal anatomy, including the structure and function of cells, tissues, and organs. Explore the various types of tissues such as epithelial, connective, muscular, and nervous tissues, as well as different postures like plantigrade and digitigrade. This quiz covers essential concepts that are fundamental to understanding mammal biology.