Biology 2 - Exam 3 (Plants, etc.)

What makes up more than 98% of all biomass?

Plants

What organisms did plants evolve from?

And what key features were passed down?

Freshwater algae (charophytes-stoneworts)

- Cellulose cell wall

- Apical Cells

- Plasmodesmata

- Placenta

How many key events in plant evolution?

4

4 key plant evolution events

1. Non-vascular plants

2. Seedless vascular plants

3. Gymnosperms and angiosperms

4. Flowering plants

Non-vascular plants

Do not have any tissues to transport water and nutrients

Nourishment of multicellular

embryo within female plant

Seedless vascular plants

Plants that have vascular tissue but reproduce by spores (ferns, club mosses, and horsetails)

Gymnosperms and Angiosperms

Produce seeds

Flowering plants

This group consists of true vascular plants that produce flowers and pollen. Their seeds are protected by fruits and nuts.

- Attract pollinators

Alternation of generations

A life cycle in which there is both a multicellular diploid form, the sporophyte, and a multicellular haploid form, the gametophyte; characteristic of plants and some algae.

Alternation of generations means that plants alternate between two different life stages, or generations, in their life cycle; a haploid stage called gametophyte and a diploid stage called sporophyte. The terms haploid and diploid refer to the number of chromosomes contained in the cells.

Common Characteristics of Animals

Multicellularity, Heterotrophs, No Cell Walls, Nervous Tissue, Muscle tissue, Sexual Reproduction, extracellular matrix, characteristic cell junctions, special clusters of hox genes, similar rRNA, Characteristic cell junctions:

No cell walls allows for:

Flexibility

Nervous tissue allows for:

Rapid response

Muscle tissue allows for:

movement

Sexual reproduction in animals:

small, mobile sperm; larger egg

- diploid from a blastula

- Metamorphosis

Extracellular matrix has:

collagen

Collagen

structural protein found in the skin and connective tissue

Hox genes

series of genes that controls the organs and tissues that develop in various parts of an embryo--> patterns body axis

Characteristic cell junctions:

anchoring, tight, and gap junctions.

Multicellular animals emerged:

at the end of the Proterozoic eon (over 600 mya)

The first animals were:

Invertibrates

A sudden increase in animal diversity occurred during:

The Cambrian explosion

3 Reasons why animal diversity increased during the Cambrian Explosion:

1. Favorable environment - warm temperatures, increases in atmospheric and aquatic oxygen, development of ozone layer

2. Evolution of the Hox gene complex

3. §An evolutionary "arms race"

4. No Dinosaurs as predators

The first vertebrates were:

Fishes (520 mya)

Along with the rise of fish as the first vertebrates, _________ began to colonize land.

Plants, which provided a food source for land animals.

Animal adaptations to land

-Animals developed lungs, internal fertilization, amniotic egg

what animal dominated the earth for millions of years?

Reptiles

2 major categories of animals

invertebrates and vertebrates

Invertebrates

- No backbone

- 97 - 99% of all animals

- Heterogeneous assemblage of groups

- No single positive character in common

- Examples: sponges, jellyfish, "worms," crustaceans, insects, clams, snails, sea stars

Vertebrates

- Have a backbone

- 1% of all animals

• 1 phylum (Chordata)

• Examples:

fish, frogs, birds, reptiles, mammals, humans

Bauplan

general body plan of a group of animals

Basic design (ground plan) of each major taxonomic group; starting point

establish evolutionary relationships

- Framework to organize and compare bauplans

Functional Principles

physical, chemical, biological, physiology, development, ecology

Body Design determined by:

1) Type of Environment

2) Size of Animal (SA/V ratio)

3) Mode of Existence

4) Constraints of Genome

(ancestral design)

Metazoa

all animals

cells-->tissues-->Epithelia and Connective tissue

Animal body size compared to other life forms

We are huge

Sea urchin --> stadium. 0.5 mm to 1 m

Dinoflagellate -->Grapefruit 2 µm to 0.5 mm

Pneumococcus --> mustard seed < 1µm to < 2 µm

Animal levels of organization

1. Cellular Level - Porifera

2. Cell-tissue Level - Cnidaria, Ctenophora

3. Tissue-organ Level - Platyhelminthes

4. 4. Organ-system Level - Everyone else (Lophotrochozoa, Gnathifera, Ecdysozoa, Chordates, etc.)

Porifera

the phylum of sponges

- Aggregations of cells, groups with specialized functions

- Division of labor

Cell-tissue level: Cnidaria, Ctenophora

- Groups of similar cells arranged in definite patterns or layers with a common function = Tissue

- Many scattered cells still present

4 types of tissue in the body

1. Epithelial

2. Connective

3. Muscle

4. Nervous

Tissue organ level - Platyhelminthes

- Tissues arranged into organs

- Organ consists of multiple tissue types and has a very specialized function

Organ-system Level - Everyone else (Lophotrochozoa, Gnathifera, Ecdysozoa, Chordates, etc.)

- Groups of organs working together to perform a particular function

- Systems associated with basic body functions

- 11 body systems

11 body systems

1. Integumentary

2. Skeletal

3. Muscular

4. Nervous

5. Endocrine

6. Cardiovascular

7. Lymphatic

8. Respiratory

9. Digestive

10. Urinary

11. Reproductive

integumentary system

Consists of the skin, mucous membranes, hair, and nail

Protection, respiration, nutrient uptake

coloration, temp.regulation

skeletal system

Protects and supports body organs and provides a framework the muscles use to support movement. Made up of bones and joints

Muscular System

Allows manipulation of the environment, locomotion.

nervous system

Reception of Information, Analysis, Coordination of Response

endocrine system

Regulation of growth, metabolism, and sexual development/function

circulatory system

Delivery of O2, nutrients, hormones; removal of CO2, ammonia and metabolic wastes

lymphatic system

Composed of a network of vessels, ducts, nodes, and organs. Provides defense against infection.

Transport, Protection,

Fat Absorption

respiratory system

A system of organs, functioning in the process of gas exchange between the body and the environment, consisting especially of the nose, nasal passages, nasopharynx, larynx, trachea, bronchi, and lungs.

digestive system

Breaks down food into absorbable units that enter the blood for distribution to body cells.

Collection of Food

Breakdown of Nutrients

Absorption of Nutrients

Egestion of Wastes

urinary system

Eliminates nitrogenous wastes from the body. Regulates water, electrolyte and acid-base balance of the blood.

Water balance,

Nitrogenous waste elimination

Reproductive system

Procreation

Digestive ---> Circulatory

The digestive system breaks food down into nutrients, water, and solutes that are then absorbed by the circulatory system and delivered to cells all over the body.

Respiratory

Oxygenated blood is pumped through the heart and then circulated through cells. Red blood cells move oxygen and carbon dioxide through the blood. Alveoli exchange gas with capillaries.

Diffusion

Gills

Tracheal Syst

Lungs

Circulatory

water, solutes

immune system

A system (including the thymus and bone marrow and lymphoid tissues) that protects the body from foreign substances and pathogenic organisms by producing the immune response

Non-specific defenses

Specific defenses

(Abs, T-cells)

excretory system

elimination of

water, salts,

N-wastes (ammonia, urea, uric acid)

Metabolism

C6H12O6 + 6O2 6CO2 + 6H2O + 27-29 ATP + Heat

2 Body forms

Radiata and Bilateria

Radiata

Radial symmetry, no right and left halves (both) identical

- Sac body plan --> mouth is same as butt

Bilateria

Definite Right and Left Halves with distinct planes

Tube within a tube body plan --> mouth and butt are different

3 Bilateria planes

Frontal plane - dorsal/ventral

Sagittal plane - right/left

Transverse - anterior/posterior

Cephalization

concentration of sense organs and nerve cells at the front of an animal's body

animal life cycle

Sperm and egg are produced by meiosis

A sperm and egg fuse at fertilization

Results in a zygote

The one-celled stage of an individual of the next generation

Undergoes mitosis

Results in multicellular embryo that gradually takes on features determined when zygote was formed

All growth occurs as mitotic division

As a result of mitosis, each somatic cell in body

Has same number of chromosomes as zygote

Has genetic makeup determined when zygote was formed

germ layers

- Group of cells that behave as unit during

early embryonic development;

Morphogenesis

Give rise to tissue/organ/system

3 germ layers

ectoderm, mesoderm, endoderm

Endoderm

the inner germ layer that develops into the lining of the digestive and respiratory systems

Mesoderm

middle germ layer; develops into muscles, and much of the circulatory, reproductive, and excretory systems

Ectoderm

outermost germ layer; produces sense organs, nerves, and outer layer of skin

Diploblastic

ectoderm and endoderm

Mesoglea in the middle

coelom

fluid-filled space around the gut in which organs are suspended

Benefits: more space, more SA, storage, support (Hydrostatic Skeleton),

incr body size/complexity

Acoelomate

an animal that lacks a coelom, or body cavity

blastocoelomate/pseudocoelomate

A loosely grouped set of animals that have a fluid-filled body cavity, or blastocoel. This is not a true group, and all blastocoelomates do not represent a single lineage of the animal phylogeny.

Eucoelomate

An organism that has a complete body cavity where the ectoderm and the endoderm is lined by mesoderm

Segmentation

Annelida/Arthropoda/Chordata

Body may be divided into regions called segments

Occurs in annelid worms, arthropods, and chordates

Allows specialization of body regions

Annelida segmentation

very segmented, each ring is a segment

Arthropoda segmentation

head, thorax, abdomen

Specialized appendages on many segments

Chordata Segmentation

segmented - body muscles and backbone

Protostome

1st embryonic opening becomes the mouth (most of Bilateria: Annelids, Arthropods, Molluscs)

Deutorostomes

Blastopore becomes anus and mouth is formed from second opening that develops

8 cell stage

The result of a zygote that undergoes cleavage

the embryo undergoes a process known as compaction to become a morula, a compact smooth spherical structure (Figure 13-1D).

Protostomes vs. Deuterostomes cleavage

Protostomes

- Determinate Cleavage

- Mosaic Embryo

Deuterostomes

- Indeterminate Cleavage

- Regulative Embryo

stem cells

unspecialized cells that are able to renew themselves for long periods of time by cell division

Pluripotent

- retain ability to develop into any cell type - retain capacity to divide

(Adult stem cells = multi- or uni- potent)

Protostomes Vs Deuterostomes Coelom Formation

Protostomes

- Schizocoely

- Blastopore becomes mouth

Deuterostomes

- Enterocoely

- Blastopore becomes anus

How to use molecular techniques to classify animals

•Compare similarities in DNA, RNA, and amino acid sequences

•Closely related organisms have fewer differences than those more distantly related

Advantage over morphological data in that genetic sequences are easier to quantify and compare

Example: A,T,G, and C of DNA

Morphological data are more subjective

Molecular views of animal diversity

Often focus on:

1. Gene for small subunit ribosomal RNA (SSU rRNA)

- Universal in all organisms - Changes slowly over time

2. Hox genes

- Found in all animals

- Duplications in these may have led to evolution of complex body forms

Phylogenies constructed using SSU rRNA and Hox genes are similar and often agree with those based on morphology

Animal clades

•Parazoa (Porifera)

•Placozoa

•Cnidaria

•Ctenophora

•Bilateria

secondary metabolites

organic compounds that are not directly involved in the normal growth, development, or reproduction of an organism

Synthesis of molecules that are NOT essential for cell structure and growth

Unique to a species or group of species

secondary metabolites are common in

plants (esp. Angiosperms), bacteria, fungi, animals (esp. soft-bodied)

secondary metabolites role:

Roles in defense, attraction, protection, competition

Secondary metabolite characteristics

Many taste bad or are toxic (chemical weapons)

Strong smell or bright color to attract or repel

Secondary metabolites are used to make:

60% of the drugs currently on the market

4 types of secondary metabolites

1. Phenolics

2. Alkaloids

3. Terpenoids

4. Polyketides

Phenolics

Antioxidants with intense flavors and smells Flavonoids - Vanilla, Chocolate, Tannins, Lignins

-Destroy vegetative bacteria, fungi, and some viruses

-Able to act in the presence of organic matter

-Too toxic to use as antiseptics

Alkaloids

potent plant chemicals that contain nitrogen

Bitter-tasting molecules for defense

Caffeine, Nicotine

Atropine, Scopolamine - deadly nightshade

Capsaicin - Chile peppers

Cocaine - Coca plant

Ephedrine

Codeine, Morphine - opium poppy

poppy plant - Papaver somniferum

Opioid Crisis = Worst Drug Crisis in American History

Every day: 130+ Americans die after overdosing on opioids. (NIDA 2019)

Morphine, Codeine, Heroin, Oxycontin/Oxycodone, Vicodin, Methadone, etc.

FENTANYL

Opioid Crisis

Current drug crisis caused by overprescription of painkillers and heroin that is plaguing the nation.

Every day, 136+ Americans die after overdosing on opioids

•More than 1 million people have died since 1999 from a drug overdose.

•Opioids are a factor in 72% of overdose deaths

•Overdoses involving opioids killed nearly 80,816 people in 2021

•9.6x Increase in deaths since 2000

(93% fentanyl; 13% prescription