Bio 111 Exam One Flashcards
Taxonomy
-The science of classification
-Name all living organisms
-Classify organisms into group
Parts of the scientific name
-First name is genus (capital)
-Second name is species (lowercase)
Genus
-category directly above species
-human genus: Homo
Species
-made of individuals that can breed together
-human species: sapiens
Human scientific name
Homo sapiens
Three categories taxonomists study
-Monophyletic
-Paraphyletic
-Polyphyletic
-used to study similarities/differences between organisms
Monophyletic
-complete study
-consists of ancestor and all descendants
-ancestor always at bottom of tree
-also known as a clade
Paraphyletic
-Consists of ancestor and some (not all) descendants
Polyphyletic Group
-includes numerous descendants but not the ancestor
Eight Levels of Taxonomy
-Domain
-Kingdom
-Phylum
-Class
-Order
-Family
-Genus
-Species
Domain
-broadest category
-most members
-currently three Domains of Life
Three Domains of Life
-Domain Bacteria
-Domain Archaea
-Domain Eukarya
Domain Archaea
-prokaryotic cells
-live in harsh environments
-maybe first living cells
Domain Bacteria
-prokaryotic cells
-includes all bacteria
-live with us in our environment
Domain Eukarya
-Eukaryotic Cells
-structurally diverse
-organized into four kingdoms:
-Protista
-Fungi
-Plantae
-Animalia
Kingdom Protista
-single celled eukaryotes
-live in bodies of water
-microscopic
Kingdom Fungi
-fungus
-molds
-closer to animals than plants
Kingdom Plantae
all plants
Kingdom Animalia
all animals
Integumentary System
-skin
-largest organ system
-covers body
-protects internal organs
-holds in moisture
-prevents dehydration
-fixes cuts and burns
-strong, holds shape
-helps homeostasis
-produces vitamin d when exposed to sun
-contains sensory receptors
Layers of the Skin
-Epidermis
-Dermis
-Hypodermis
-Fat layer
Epidermis
-outer covering
-contains dead cells and living cell layer
Dermis
-inner/middle layer
-contains collagen/elastin
Hypodermis
-inner/deepest layer
-subcutaneous layer
Fat layer
-insulation and cushioning
Sensory Receptors
-detects pressure
-detects texture
-detects temperature
Cells of Epidermis
-keratinocytes
-melanocytes
Keratinocytes
-produces keratin
-produces vitamin D
Melanocytes
-produces melanin
-used to protect skin from UV-B rays
Cells of Epidermis
-Langerhans cells
-Merkel cells
Langerhans Cells
-involved in defense
-phagocytosis of bacteria and viruses
Merkel cells
-sensory cells
-touch reception
-senses temperature and textures
Accessory Structures of Dermis
-hair follicles
-sebaceous glands
-sweat glands
-sensory receptors
Sebaceous glands
-Oil glands
-Keeps skin moist
Sweat glands
-secrete sweat to maintain body temperature
-sweat cools down body
Sensory receptors
-nerves
-sense environment
Animal Skeleton Function
-support shape
-protection of internal organs
-movement
-mineral storage (calcium)
-blood cell formation (bone marrow)
Types of Skeletons
-Hydrostatic Skeletons
-Exoskeletons (shells)
-Endoskeletons (internal bones)
Hydrostatic Skeletons
-consists of fluid held under pressure in closed body
-found in worms
Exoskeletons
-shells
-can be made of calcium carbonate or chitin
-found in mollusks and arthropods
Endoskeletons
-consists of hard supporting elements (bones)
Bones in Mammalian Skeleton
-206 bones
-smallest bone: ear bones
-largest bone: thigh bone
-some bones fused
-some connected at joints
Joint
location where bone meets bone
Cartilage
gel like material between bones (joints)
Ligaments
elastic fiber that connects bones at joints
Tendons
attach muscles to bones
Types of cells in bone
-Osteoblasts
-Osteoclasts
Osteoblasts
-build bone
-deposit calcium to harden to bone
-converts cartilage into bone
-slow down with age
Osteoclasts
-breakdown bone
-remain active through life
Musculoskeletal System
-muscles allow bone to move
-muscles and bone work together
Three types of muscle
-Skeletal Muscle
-Smooth Muscle
-Cardiac Muscle
Skeletal Muscle
-muscle attached to the skeleton
-functions in movement of body
-voluntary
Smooth Muscle
-line walls of stomach and intestines
-involuntary movement
-peristalsis muscle movement
Cardiac Muscle
-muscle in heart
-involuntary
-contains lines of intercalated disks
Muscle Movement
-move by contracting and relaxing
-contracting; shorten
-relaxing; lengthen
Content of Skeletal Muscle
-made of bundles of muscle cells (sarcomeres)
Sarcomere
-basic unit of contraction in muscles
-contain actin and myosin contractile proteins
-made of thin filaments made of actin
-made of thick filaments composed of myosin
-shorten to contract movement
-requires calcium and ATP energy
Gametes
-sperm
-egg
-haploid cells (n=23)
unite to create diploid cell (2n=46)
Gametogenesis
formation of gametes
Spermatogenesis
-Formation of sperm inside testes
-continuous throughout life
-hundreds of millions of sperm produced per day
Spermatogonium
-undergo meiosis to form sperm
-produce 4 sperm
Sperm Structure
-Head
-Midpiece
-Tail
Sperm Head
-contains nucleus
-23 chromosomes, including X or Y
-Surrounded by acrosome
Acrosome
contains digestive enzymes to digest outer surface of egg
Sperm Midpiece
-contains mitochondria
-provides ATP energy for sperm movement
Tail
-flagella
-allow movement
Oogenesis
-formation of ovum
-unequal cell division
-produces one mature egg
-only one of four cells becomes egg
-females born with all eggs produced in lifetime
Spermatogenesis vs. Oogenesis
-all four cells produce sperm, only one egg produced
-sperm produced throughout lifetime, oogenesis stops at menopause
-sperm production continuous
Parts of Ovum
-Corona Radiata (protects egg)
-Zona Pellucida (jelly coat)
-Cell membrane
-Vitelline Membrane
-Nucleus
-Cytoplasm
Zygote
fertilized egg
Five Stages of Development
-Fertilization
-Cleavage
-Gastrulation
-Organogenesis
-Morphogenesis
Fertilization
-union of egg and sperm
-forms diploid zygote
Cleavage
-rapid cell division w/out growth
-formation of morula, followed by blastula
Gastrulation
-rearranges cells of blastula into three tissue layered embryo (involution)
-embryo called the gastrula
-characterized by cell migration, not division
-gastrula made up of embryonic tissue layers: endoderm, ectoderm, mesoderm
Organogenesis
-formation of the organs from embryonic layers
-ectoderm is outer layer
-endoderm is digestive tract
-mesoderm between ectoderm and endoderm
-each layer forms specific organs
Morphogenesis
formation of body
Acrosomal Reaction
-triggered when sperm contacts egg
-acrosome releases enzymes to digest outer egg covering
-acrosomal process proteins bind to vitelline layer receptors
-allows for species specific fertilization
Fusion
-fusion of plasma membrane of sperm and egg
-allows sperm nucleus to enter
Cortical reaction
-Nucleus pops cortical granules to release Calcium (Ca^+2)
-creates fertilization envelope (hardened outer coating)
Fertilization Envelope
-visible as halo around egg
-prevents polyspermy (multiple sperm entering egg)
Steps of Fertilization
-Contact
-Acrosomal Reaction
-Growth of acrosomal process
-Fusion
-Sperm nucleus entry
-Cortical reaction
Egg Activation
-rise in calcium increases rates of cellular respiration and protein synthesis
-sperm nucleus and egg nucleus join
-cell division begins 12-36 hrs after fertilization
Types of cleavage
-Interdeterminate cleavage
-Determinate cleavage
Interdeterminate Cleavage
-each cell produced by cleavage can develop into complete embryo (ex. identical twins)
Determinate Cleavage
each cell has its own developmental process determined
Morula
-solid ball of cells formed during cleavage
Blastula
-forms from morula during cleavage
-hollow ball of cells
-empty space within called blastocoel
-made of two parts: trophoblast and inner cell mass
ectoderm
-outer layer of embryo
-forms epidermis of skin
-forms nervous systems
-forms brain
-forms mouth and teeth
-forms eyes
mesoderm
-forms skeleton
-muscles
-kidneys
-reproductive system
-heart
endoderm
-digestive tract
-liver
-pancreas
-lungs
-thyroid gland
neurulation
-forms brain and spinal cord
-cells of ectoderm flatten to form neural plate
-neural plate folds and forms neural tube
-neural tube produces brain and spinal cord
-neural crest develops around neural tube
-neural crest becomes notochord
-notochord develops into vertebrae
Implantation
-morula enters uterus
-occurs at blastula stage
-blastula imbeds in inner layer of uterus (endometrium)
Blastula trophoblast
-outer layer
-imbeds into endometrium
-forms the placenta
Blastula inner cell mass
becomes the embryo
Extra-Embryonic Membranes
-Chorion: gas exchange
-Amnion: encloses amniotic fluid; insulates embryo
-Yolk sac: provides nutrients (until placenta in humans)
-Allantois: disposes waste
Human Gestation
-divided into three trimesters
-each trimester lasts three months
First Trimester
-main period of organogenesis
-develops organs
apoptosis
cell death
philtrum
-groove between nose and upper lip
-two sides of face develop independently from the back, meet in the middle of face
second trimister
-fetus grows and is active
-parent may feel fetal movement
-uterus grows enough for pregnancy to show
third trimester
-fetus grows
-fills space within uterus
