Biology 102 - Final Exam Study Guide Flashcards

Flashcards generated from Biology 102 lecture notes for final exam preparation.

What is natural selection and what is the typical selecting force?

The process by which random evolutionary changes are selected for by nature in a consistent, orderly, non-random way. Selecting force = environment

What is the definition of 'fitness' in biology, and how is it determined?

The ability to survive, reproduce, and produce viable offspring. It is determined by variations by DNA mutation that can be passed from one generation to the next.

What is the major difference between natural selection and artificial selection?

Natural selection is based on the adaptive characteristics of animals. Artificial selection is based on the desirable characters selected by humans

What is the major different between homologous and analogous traits. Which show common ancestry?

Analogous traits have similar function evolved separately due to similar lifestyle of habitat. Homologous traits are similar in structure but different in function. Homologous traits indicate common ancestry.

What types of evidence support the Theory of Evolution?

Anatomy, Biochemistry, Embryology, Fossils, Geography

What does it indicate if a population is in Hardy-Weinberg equilibrium?

The population is not evolving.

What are the different types of microevolution/genetic drift?

Gene Mutations, Gene flow, Genetic Drift, Non-random mating.

Name the four concepts of 'species'.

Morphological, phylogenetic, evolutionary, and biological

What is the difference between allopatric and sympatric speciation?

Allopatric speciation involves a geographic barrier, while sympatric does not.

Compare and contrast convergent and divergent evolution. What do they indicate about common ancestry?

Divergent evolution arises from a common ancestor. Convergent evolution happens when a biological trait evolves in two unrelated species due to exposure to similar environments.

What was early Earth’s atmosphere contain?

High levels of water vapor, hydrogen gas, methane, and ammonia.

What are the major eras of the Earth’s history in order from oldest to most recent?

Precambrian, Paleozoic, Mesozoic, and Cenozoic.

What are the major differences between prokaryotic and eukaryotic cells?

Prokaryotic cells are typically unicellular, smaller, have a single circular chromosome in the nucleoid region, and lack membrane-bound organelles. Eukaryotic cells can be multicellular, larger, have DNA organized into multiple chromosomes within a nucleus, and contain membrane-bound organelles.

What are the principal differences between bacteria and archaea?

Plasma membranes, cell walls, DNA replication, Gene expression

Name the 3 main shapes of bacteria.

Spirelli (spiral), Bacilli (rod), Cocci (round).

What does it mean to be a gram positive or gram negative bacterium?

Gram positive bacteria have a thick peptidoglycan cell wall and stain purple. Gram negative bacteria have a thin peptidoglycan cell wall and an outer membrane.

How do bacteria recombine DNA?

Transformation, transduction, and conjugation

What defines protists as a general category?

Eukaryotic organisms are not plants, animals or fungi. Most are unicellular.

List examples of protists.

Green algae, red algae, brown algae, diatoms, zooflagellates, amoebas, ciliates, dinoflagellates, and slime molds.

What is common among all algae?

They carry out photosynthesis.

What general role do most protists play in their ecosystem?

Serve as symbionts and produce nutrients and oxygen, and as decomposers.

Describe the general structure and feeding characteristics of fungi.

Fungi have hyphae, fruiting bodies (mushrooms), and mycelium. They have cell walls of chitin, store excess food as glycogen, and are heterotrophic, releasing digestive enzymes and absorbing nutrient molecules through external digestion.

What other organisms do fungi closely related to?

Animals. But animals are more closely related to another animal.

Describe the mycorrhizal relationship between fungi and plants.

Symbiotic fungi mycelia use hypae and large surface to channel mineral and water into plant then plant supplies products of photosynthesis to fuel metabolism of fungi.

List examples of fungi.

Zygomycota, chytridiomycota, sac fungi (including molds and yeast), and club fungi.

Give examples of vascular and non-vascular plants.

Bryophytes = nonvascular plants. Vascular plants = seedless ferns, seeded gymnosperms and angiosperms.

What adaptations needed to occur for plants to move to land and grow tall?

Adaptations were developing a shoot, incorporated more rigid molecules lignin, vascular tissues like xylem and phloem, waxy cuticle and stomata, poisonous and sweet metabolites to deter predators and attract animals for pollination.

Describe the concept of alternation of generations and how it functions in plants.

A gametophyte producing gametes. Fertilization of gametes to form a diploid zygote. The zygote developing into a sporophyte.(diploid) The sporophyte produces haploid spores through meiosis. The spores developing into a new gametophyte, restarting the cycle

Describe how xylem and phloem help a plant grow tall.

Xylem conducts water/minerals from roots to leaves and is lignified for mechanical strength support. Phloem transports products of photosynthesis throughout the entire plant.

Why is water an important part of seedless vascular plant reproduction?

Reproduction depends on water during fertilization.

List the 4 seedless vascular plants discussed.

Club mosses, horsetails, whisk ferns, ferns

Distinguish gymnosperms from angiosperms. Which evolved most recently?

Gymnosperms are naked seeds, cones, have separate female and male gametes, pollination by wind, all have ovules exposed on scale. Angiosperms are flowering plants and anthophyta. Angiosperms evolved most recently.

How do/did animals contribute to the evolution of seed plants?

Through pollination and seed dispersal.

What 8 characteristics define the animal kingdom?

Multicellularity, complex tissue structure, heterotrophs, active movement, form and size, reproduction, offspring pass through developmental stages, determined/fixed body plan

What 4 types of tissues are found in animals?

Epithelial, connective, muscle, nervous

Describe the 4 features used to classify animals.

Symmetry, number of tissue layers, origin of mouth and anus, body plan and cavities

How was animal phylogeny originally determined? How is it determined now?

Originally animals were classified by morphological characteristics, now use biochemical, molecular, and genetic evidence.

When did the Cambrian period occur?

542-488 mya.

How many mass extinction events are there in history? What were their causes?

5, likely due to drastic climate change caused by asteroids and/or tectonic events, among other causes.

How does that differ from current day extinction rates?

Now they are human related and are 1000 times the background rate.

What makes up invertebrates and vertebrates?

Invertebrates: Porifera, Annelida, Nematoda, Platyhelminthes, Mollusca, Cnidaria, Arthropoda, Echinodermata. Vertebrates: Chordata

What 4 common features do all chordates have?

Notochord, dorsal hollow nerve cord, pharyngeal gill slits, post-anal tail

What makes an organism an amniote?

They lay eggs on land or retain them within the mother- reptiles, birds, mammals

Distinguish endothermic from ectothermic. What are humans?

Ectothermic require fewer calories but cannot maintain constant body temperature. Endothermic produce own body heat and regulate internal temperature independent of environmental temperature. Humans are endothermic.

What are the two organ systems in plants?

Shoot system and root system

What are the three types of tissues that plants have?

Dermal, ground, and vascular

What is the function of stomata?

Open to allow transpiration and gas exchanges: carbon in and oxygen and water vapor out.

How is vascular tissue arranged in monocots vs. dicots in stems and roots?

Stems: Monocots- scattered, Dicots- ringed. Roots: Monocots: ring shape around central, Dicots: x shape in center of root

Distinguish tap roots from fibrous roots. Which type of plants have which type of roots?

Tap root: single deep root found in Dicots. Fibrous root: bunch of thin roots found in Monocots

What is the purpose of root hairs?

Increase surface area of roots leading to better water/nutrient absorption

Where does primary growth in plants occur?

Apical meristem - in both roots and shoots.

What four things do plants need from their environment?

Water, sunlight, carbon dioxide, essential inorganic nutrients/minerals

What makes a nutrient 'essential'?

Must be obtained from the environment, plant can’t make

How are minerals absorbed by plants?

Minerals are absorbed into roots using active transport, ATP

What does xylem carry and in which direction(s)? Alive or dead?

Xylem carries water and minerals from the roots to the leaves. DEAD cells

Define water potential. Which direction does water always flow?

Water potential is the mechanical energy of water. It always moves from high to low.

Why does water move INTO the roots? Be able to explain how this relates to water potential.

Because of osmotic pressure. Ions/minerals are higher inside of the root epidermis, water always moves from HIGHER area to LOWER areas. Water potential determines the direction water moves in

In addition to root pressure, what two phenomena contribute to the ability of water to reach the top of tall plants and trees?

Cohesion and adhesion

What does the phloem carry and in which direction(s)? Alive or dead?

The phloem carries sugars from leaves to other parts of the plants. Alive

In what ways do plants respond to light?

Photomorphogenesis, photoperiodism, and phototropism.

What are some mechanisms by which plants protect themselves from herbivores?

Intact and impenetrable barrier Bark and waxy cuticle Thorns Spines Secondary: toxins and enzymes

What generation do flowers belong to in plants?

Gametophyte generation

Identify the female and male reproductive structures in plants.

Carpel = female part of the flower: ovary, stigma, style. Stamen = male part of flower: anther, filament.

Where does pollen form?

In the anther

How does self-pollination differ from cross-pollination?

Self-pollination: pollen from the anther is deposited on the stigma of the same flower, or another flower on the same plant. Cross-pollination: transfer of pollen from the anther of one flower to the stigma of another flower on a different individual of the same species.

What are the major ways in which pollination can occur?

Biotics like animals, insects, bats, and birds and abiotic like wind and water.

How are seeds an important adaptation for plants?

Maintain dormancy under unfavorable conditions, protect young plant when it is most vulnerable, provide food for the embryo until it can produce its own food, facilitate dispersal of the embryo

What are fruits?

Mature ovaries

What are the major body sectioning?

Frontal/coronal, transverse, or sagittal

What are the differences between positive and negative feedback loops?

Positive feedback loop maintains the response to a stimulus. Negative feedback loop counteracts internal changes.

What are the four different types of tissues found in animals?

Epithelia, connective tissues, muscles, neurons

How are epithelial cells distinguished?

Shape and layers.

What common features do all connective tissues have?

Consist of cells, fibers and gel-like substance (contains collagen, elastin and reticular fiber). Bone, cartilage, fat, blood and lymphatic tissue.

What are some examples of connective tissues?

Blood, loose connective, adipose, cartilage, bone, and dense

What are the three types of muscle tissues?

Skeletal, smooth, and cardiac.

What two types of cells are found in nervous tissue? What is the purpose of each?

Neurons transmit signals. Glial cells support neurons.

Distinguish asexual and sexual reproduction in animals

Asexual involves 1 parent with identical offspring via budding, splitting, or regenerating from fragments. Sexual reproduction involves 2 parents with genetic variation.

Define the process of fertilization.

Union of sperm and egg to form a zygote.

What are the advantages and disadvantages to external fertilization with broadcast spawning?

Advantages: higher genetic diversity. Disadvantages: low survival and requires water.

What are some advantages to internal fertilization?

Protects fertilized egg from dehydration , limits predation , enhances the fertilization of eggs by a specific male , survival rate is higher

What is the pathway of sperm beginning in the testes to exit from the body?

Testes > epididymis > vas deferens > urethra > OUT

On a very basic level, what is semen composed of? Where does the fluid enter the process and how does it help the sperm?

Semen = sperm cells + fluid. The fluid comes from seminal vesicles, prostate gland, bulbourethral glands and nourishes sperm, protects them from acidity and helps them swim

What part of the brain helps to control hormonal secretions? What other gland is involved?

Hypothalamus and Pituitary gland

What is the pathway of an egg from ovary to birth of baby? Where does fertilization typically occur?

Ovary > fertilization > uterus > cervix > vagina > BIRTH. Fertilization occurs in the fallopian tubes

Over the course of the month, what happens to the endometrium?

Thickens for pregnancy and if no pregnancy then it sheds (CRAMPS)

What happens on Day 1 of the uterine cycle?

Menstruation begins

How long does an egg live after ovulation? How long do sperm survive once released?

Egg lives 24 hours. Sperm survives up to 5 days.

Why do females experience menopause?

Ovaries stop releasing eggs and hormones increase with age, eggs are old since they were formed before birth

What are the three phases of digestion?

Cephalic, gastric, intestinal

How does food get from the mouth to the stomach?

Food is chewed by teeth and moistened by saliva, amylase digests strach and lipase digests fats. The tongue mixes chewed food with salvia and makes bolus. It goes down the esophagus to the stomach through peristalsis.

What are some accessory organs for digestion?

Salivary glands, liver, pancreas, gallbladder

Where in the digestive system does absorption take place?

Small intestine

What is chyme? Which opening controls it's release and to where?

Chyme is food mixed with gastric juices. The pyloric sphincter controls release between stomach and small intestine.

What is the purpose of having villi in the small intestine?

Increasing surface area for absorption.

Where are each of the major macromolecules (carbs, lipids, proteins) digested?

Proteins in stomach (pepsin), carbs in mouth (amylase), lipids in small intestine (pancreatic lipase), nucleic acids in stomach and small intestine (pepsin)

What is the main function of the nervous system?

Receiving sensory input, performing integration, generating motor output.

What is the purpose of the spinal cord?

Means of communication between the brain and spinal nerves and enter for many reflex actions

The two main divisions of the nervous system are the CNS and PNS. What makes up the CNS? The PNS? What subdivisions are there in the PNS?

Central nervous system (CNS) includes the brain and spinal cord. Peripheral nervous system (PNS) contains cranial nerves and spinal nerves. Somatic and autonomic divisions are in the PNS

Describe the structure of a neuron. Be able to label the parts.

Cell body is the nucleus. Dendrite receives signals from sensory receptors and axon, which conducts nerve impulse is covered by myelin sheath. Long axon= nerve fiber.

What is the function of neurotransmitters in neuronal signaling?

Neurotransmitters are chemicals that are secreted from one neuron by the axon terminal into the synaptic cleft and picked up by the dendrites of the next neuron in order pass the signal along.