2nd Semester 14 - BIOLOGY JUNCTION

Pzsol Photosynthesis

Photosynthesis

Answer Key:

All organisms use energy to carry out their life functions. Some organisms obtain this energy from sunlight. The process by which this energy transfer takes place is called photosynthesis. Photosynthesis involves a biochemical pathway in which the product of one reaction is consumed in the next reaction. Autotrophs are organisms that carry on photosynthesis and includes plants and other organisms containing the green pigment chlorophyll. Autotrophs use carbon dioxide and water to make oxygen and the simple sugar glucose. The pigment chlorophyll absorbs light energy from the sun during the light reactions. Accessory pigments also in the chloroplast absorb other wavelengths of light that chlorophyll does not absorb. These accessory pigments are responsible for other colors we see in plants such as red, orange, and yellow. Chloroplasts are surrounded by a double membrane. Inside chloroplasts is a system of membranes arranged as stacks of flattened sacs called granum. Each sac in the stack is called a thylakoid. The thylakoids are surrounded by a solution called the stroma. The dark reactions of photosynthesis take place in the stroma. Most chloroplasts are found in the leaves of plants. The underside of a leaf contains openings called stomata where gases such as oxygen and carbon dioxide enter and leave. These openings or stomata are closed during the hottest times of the day by cells called guard cells.

Pzsol Viruses

Viruses

Answer Key:

1) virus

2) virology

3) stanley

4) mosaic

5) crystallization

6) metabolism

7) antiviral

8) nonliving

9) capsid

10) glycoprotein

11) genome

12) transcriptase

13) envelope

14) spikes

15) nanometer

16) replicate

17) protein

18) nucleic

19) hiv

20) immunodeficiency

21) icosahedron

22) helix

23) host

24) adenovirus

25) retrovirus

26) viroid

27) prion

28) intracellular

29) bacteriophage

30) escherichia

31) collar

32) tail

33) lytic

34) virulent

35) assembly

36) lysis

37) attachment

38) lysogenic

39) temperate

40) prophage

41) injection

42) inactivated

43) attenuated

44) smallpox

45) measles

46) influenza

47) jungles

Reptile

Reptiles All Materials © Cmassengale

Evolution of Reptiles:

Reptiles were 1st vertebrates to make a complete transition to life on land (more food & space)
Arose from ancestral reptile group called cotylosaurs (small, lizard like reptile)
Cotylosaurs adapted to other environments in Permian period
1. Pterosaurs – flying reptiles
2. Ichthyosaurs & plesiosaurs – marine reptiles
3. Thecodonts – small, land reptiles that walked on back legs
Mesozoic Era called “age of reptiles”

Dinosaurs dominated life on land for 160 million years
Brachiosaurs were largest dinosaurs
Herbivores included Brontosaurus & Diplodocus, while Tyrannosaurus were carnivores
Dinosaurs became extinct at end of Cretaceous period
Mass extinction of many animal species possibly due to impact of huge asteroid with earth; Asteroid Impact Theory
Amniote (shelled) egg allowed reptiles to live & reproduce on land

Amniote Egg:

Egg had protective membranes & porous shell enclosing the embryo
Has 4 specialized membranes — amnion, yolk sac, allantois, & chorion
Amnion is a thin membrane surrounding a salty fluid in which the embryo “floats”
Yolk sac encloses the yolk or protein-rich food supply for embryo
Allantois stores nitrogenous wastes made by embryo until egg hatches
Chorion lines the inside of the shell & regulates oxygen & carbon dioxide exchange
Shell leathery & waterproof
Internal fertilization occurs in female before shell is formed

Section 1 Review

Terrestrial Adaptations:

Dry, watertight skin covered by scales made of a protein called keratin to prevent desiccation (water loss)
Toes with claws to dig & climb
Geckos have toes modified into suction cups to aid climbing
Snakes use scales & well developed muscular & skeletal systems to move
Lungs for respiration
Double circulation of blood through heart to increase oxygen to cells
Partial separation in ventricle to separate oxygenated & deoxygenated blood
Ectothermic – body temperature controlled by environment
May bask or lie in sun to raise body temperature or seek shade to lower body temperature; known as thermoregulation
Water conserved as nitrogen wastes excreted in dry, paste like form of uric acid crystals

Section 2 Review

Modern Reptiles:

Only 4 living orders remain
Found worldwide except in coldest ecosystems
Orders include —– Rhyncocephalia (tuatara lizard), Chelonia (turtles & tortoises), Squamata (lizards & snakes), & Crocodilia (alligators, caimans, and crocodiles)

Rhyncocephalia:

Only one living species, Spenodon punctatus, (tuatara lizard)
Live on islands off the coast of New Zealand

Tuatara
Tuatara

Spiny crest running down back
Grows up to 60 cm in length
Has 3rd eye on top of head (parietal eye) that acts as a thermostat
Most active when temperatures are low (nocturnal)
Often burrow during the day
Feed on insects, worms, & small animals at night

Chelonia:

Includes turtles and tortoises
Aquatic, but lay eggs on land
Body covered with shell composed of hard plates & tough, leathery skin
Carapace or dorsal surface of shell fused with vertebrae & ribs
Plastron is ventral shell surface
Shape of shell modified for habitat
Dome shaped shell helps to retract head & limbs in tortoises

Galapagos Tortoise

Water-dwelling turtles have streamline, disk shaped shell to rapidly move in water

Spotted Turtle

Forelimbs of marine turtles modified into flippers

River & sea turtles migrate to breeding areas where they hatched to lay their eggs on land

Crocodilia:

Includes crocodiles, alligators, caimans, & gavials
Direct descendants of Archosaurs
Carnivorous (wait for prey to come near & then aggressively attack)
Eyes located on top of head so they can see when submerged
Nostrils on top of snout to breathe in water
Valve in back of mouth prevents water from entering airway when feeding underwater
No parental care of young in most species except Nile crocodile that carry young in their jaws & guards nest
Crocodiles are tropical or subtropical, usually nocturnal, reptiles found in Africa, Asia, South America, & southern Florida

Australian photographs - crocodile
Australian Crocodile

Alligators are found in China & the southern United States

American Alligator

Caimans are native to Central America & resemble alligators

Black Caiman

Gavials, living only in India & Burma, are fish eating reptiles with very slender, long snouts

Gavial

Squamata:

Includes snakes & lizards
Snakes probably evolved from lizards during the Cretaceous period
Snakes have 100-400 vertebrae each with a pair of ribs & attached muscles for movement
Interaction of bone, muscles, & skin of snakes allows them 3 ways to move — lateral, rectilinear, & side winding
Lateral undulations:
1. Most common
2. Head moves side to side causing wave of muscular contractions
3. Snake uses sides of its body to push off of ground
4. Snake moves forward in S-shaped path
Rectilinear Movements:
1. Muscular force applied to belly & not sides of snake
2. Scutes or scales on belly catch on rough surfaces
3. Body relaxes & then moves forward slowly
Sidewinding:
1. Used by some desert snakes
2. Sideways movement of body
3. Head vigorously flung from side to side
4. Whiplike motion moves body along
Do not hear or see well but locate prey using forked tongue that gathers chemical scents
Swallow prey whole:
1. Jaws unhinge for mouth to stretch
2. Small teeth used to hold prey in mouth
3. Windpipe thrust into throat while swallowing so snake can swallow & breathe
4. Swallowing may take several hours
5. Saliva begins digestion during swallowing
Constrictors wrap body around prey & squeeze them to death (boas, pythons, etc.)
Snakes may inject venom or poison:
1. Hemotoxin – poisonous proteins attacking red blood cells (water moccasin & rattlesnake)
2. Neurotoxin – poison that works on nervous system affecting heart rate & breathing (copperhead)
Venomous snakes with 3 types of fangs — rear-fanged, front-fanged, & hinge- fanged snakes
Rear-fanged snakes bite prey & use grooved back teeth to guide venom into puncture (boomslang)
Front-fanged snakes inject poison through 2 small front fangs that act like a hypodermic needle (cobra)

Spitting Cobra

Hinged- fang snakes have hinged fangs in roof of mouth that swing forward to inject poison (rattlesnake, water moccasin, copperhead)


Rattlesnake	Water Moccasin

Often camouflaged for defense
May use signals such as cobra expanding its hood, rattlesnake shaking its rattle, or hissing for defense
Most snakes locate females by scent
Internal fertilization with no parental care
May be oviparous (eggs hatch outside body) or ovoviviparous (eggs held inside body until hatch)
Lizards:
1. Four limbs
2. Includes iguanas, geckos, skinks, chameleons, etc.
3. Rely on speed, agility, & camouflage to catch prey
4. Feed on insects & small worms
5. Some, such as anole & chameleon, can change colors for protection
6. May use active displays such as squirting blood, hissing, or inflating bodies
7. Some show autotomy (breaking off tail to escape predators)
8. Two poisonous U.S. species include Gila Monster & Beaded Lizard

Gila Monster

Komodo dragon of Indonesia is largest lizard reaching 3 meters in length

Section 3 Review

BACK

Pzsol Worms

Worms
Answer Key:

1)platyhelminthes	phylum of flatworms
2)three	number of body layers in worms
3)bilateral	symmetry f flatworms
4)dorsal	upper body surface of worms
5)ventral	lower body surface of worms
6)ectoderm	outermost cell layer of worms
7)mesoderm	middle cell layer of worms
8)endoderm	innermost cell layer of worms
9)acoelomate	solid body in flatworms
10)coelom	body cavity
11)gastrovascular	gut with a single opening in flatworms
12)absorption	how flatworms exchanges gases with their environment
13)anterior	head or front end of a flatworm
14)cephalization	anterior end with sensory structures concentrated there
15)parasite	worms that live on or inside the body of their host
16)turbellaria	class of flatworms containing the freshwater planarian
17)pharynx	extendable feeding tube on the underside of planarians
18)mucus	secreted by planarians to glide across
19)flame	excretory cells in worms that filter wastes
20)ganglia	clusters of nerve cells in worms
21)hermaphrodites	worms that make both eggs & sperm
22)trematoda	class of flatworms containing flukes
23)suckers	found on the ends of flukes to attach to hosts
24)tegument	tough outer covering on flukes
25)cestoda	class containing tapeworms
26)scolex	anterior end of a tapeworm with hooks & suckers
27)proglottids	reproductive sections of a tapeworm’s body
28)nematoda	phylum for roundworms
29)taper	shape of both ends of a roundworms body
30)cuticle	protective noncellular layer of roundworms
31)ascaris	roundworm found in pig & horse intestines
32)hookworms	intestinal parasitic roundworm with cutting plates in it’s mouth
33)trichinosis	disease that result from eating infected undercooked pork
34)pinworms	most common parasitic roundworm of children in the U.S.
35)rotifera	phylum of worms with a crown of cilia surrounding the mouth
36)mastax	muscular organ of rotifers to break down food
37)pseudocoelomates	rotifers & nematodes are examples

Quiz Bacteria

Name:

Bacteria

True/False Indicate whether the sentence or statement is true or false.
	1.	Gram-negative bacteria have a thick layer of peptidoglycan that stains purple.
	2.	Bacteria lack nuclei and therefore also lack genetic material.
	3.	Bacterial cells have membrane-bound organelles and chromosomes.
	4.	Bacterial cells are usually much larger than eukaryotic cells.
	5.	Bacteria are incapable of movement themselves; they can only get to new locations by growing toward them or by forming endospores and being carried in air or water.
	6.	Some bacteria cannot survive in the presence of oxygen.
	7.	When bacteria undergo nonreproductive genetic recombination, their bacterial chromosome is altered.
	8.	Certain antibiotics have become ineffective against certain strains of bacteria. These bacteria have developed a resistance, which may be passed on from one generation of bacteria to the next.
	9.	The photoautotrophic bacteria are the only bacteria that are indirectly beneficial to humans.
Completion Complete each sentence or statement.
	10.	Spiral bacteria are called ____________________.
	11.	Spherical bacteria are called ____________________.
	12.	Rod-shaped bacteria are called ____________________.
	13.	The procedure used to distinguish between two types of bacterial cell wall structures is called ____________________.
	14.	Protective structures that some bacteria may form under harsh conditions are ____________________.
	15.	The cell walls of Gram-negative eubacteria are composed of a combination of polysaccharide and polypeptide called ____________________.
	16.	Bacteria that obtain their energy by removing electrons from inorganic molecules, rather than obtaining energy from the sun, are called ____________________ bacteria.
	17.	In general, organisms that obtain their energy from sunlight are called ____________________.
	18.	Bacteria that are heterotrophic and feed on dead organic matter are called ____________________.
	19.	A(n) ____________________ is a substance that can be obtained from bacteria or fungi and can be used as a drug to fight pathogenic bacteria.
	20.	Many bacteria are ____________________ and play an important role in recycling carbon, nitrogen, and other elements, while other bacteria are ____________________ and assemble organic compounds from carbon dioxide, nitrogen, and other elements.