11. General Science and Life Science

Question 1

What are the 6 usual steps that the scientific method contains?

Answer 1

1. Observe some aspect of the universe.
2. Ask a question about why this thing is happening.
3. Develop a testable explanation (hypothesis) based on the theory.
4. Make a prediction based on the hypothesis.
5. Experiment and observe to test the hypothesis.
6. Use the results of the experiment to create new hypothesis.

Question 2

If a theory holds up to repeated testing, scientists gain confidence in it, and a hypothesis that’s supported consistently over time eventually comes to be considered…

Answer 2

A law, fact, or principle.

Question 3

In scientific terms, what is the difference between a law and a theory?

Answer 3

A law doesn’t say why you fall toward the pool — only that you do fall toward the pool. Laws usually rely on mathematical equation, and they’re always true. On the other hand, a theory is a detailed explanation of the phenomenon. It consists of one or more hypotheses that have been supported through repeated testing.

Question 4

Why are measurements an important part of science?

Answer 4

Because science is based on developing objective facts — evidence and results that are measurable and experiments that can be reproduced.

Question 5

What are the 3 basic units of measurement that you need to know for the General Science subtest of the ASVAB?

Answer 5

1. The meter (m) is a unit of length.
2. The liter (L) is a unit of volume.
3. The gram (g) is a unit of mass (similar to weight).

Question 6

Recite the metric prefixes, its symbols, and what it expresses in numerical terms.

Answer 6

Question 7

Recite the common metric units and their abbreviations.

Answer 7

Question 8

Recite the Imperial to Metric Conversions

Answer 8

Question 9

What is ecology? & Compare ecology and psychology.

Answer 9

Ecology is the study of the environment — more specifically, the relationship between organisms and the world around them; while, psychology is the scientific study of organisms’ behavior and thinking.

Question 10

What is an ecosystem? & Synthesize ecosystem into 3 concepts.

Answer 10

An ecosystem is a biological community of interacting organisms and their environment.

An ecosystem includes producers that make their own food and consumers that eat other things. An ecosystem also has decomposers, such as bacteria, that break down dead plants, animals, and the waste of all organisms.

Question 11

Within the ecosystem, animals can’t produce their own food, so they’re consumers, which are classified in three categories…, What are these categories? Differentiate these categories.

Answer 11

1. Carnivores - eat only meat.
2. Herbivores - eat only plants.
3. Omnivores - eat both plants and other animals.

Question 12

What is biodiversity? illustrate and compare it into three different concepts.

Answer 12

Biodiversity is the term scientist use to talk about the variety of life in the world—at—large, or in specific habitats and ecosystems.

Question 13

Who was the first to create a common scientific classification in order to study and discuss plants, animals, and other living things effectively?

Answer 13

Swedish botanist Carl Linnaeus, who published his works from 1753 to 1758, creating the Linnean taxonomic system

Question 14

What is taxonomy? illustrate it and synthesize it within 3 different concepts.

Answer 14

Taxonomy is a classification system of plants and animals that provide official names for every plant and animal, and also helps scientists understand how living creatures are related to one another. Modern-day taxonomy has its roots in the Linnean taxonomic system.

Question 15

What are the 8 main levels of the scientific classification system among organisms? Define and differentiate all of it.

Answer 15

1. Domain: A domain is a group of organisms that are similar based on characteristics such as chemistry and cell structure. The three domains are the broadest classifications and include the most kinds of organisms.
2. Kingdom: Kingdoms group organisms by developmental characteristics and whether they make their own food. The relationship between organisms in a kingdom can be extremely loose, so members may share only a few characteristics. According to scientists, five or six kingdoms exist.
3. Phylum: Phylum (plural phyla) is the next major taxonomic group. Within the kingdoms, organisms are divided into 36 phyla by general characteristics. For example, in the Animal kingdom, animals with backbones (vertebrates) are placed in a separate phylum from animals without backbones.
4. Class: Organisms in a phylum are divided into classes. In the Animal Kingdom, for example, birds, mammals, and fish all go in their own classes. Among plants, all flowering plants comprise the Angiosperm class, and all trees that bear cones, such as pines and spruces, comprise the Conifer class.
5. Order: Scientific groupings create orders, which separate organisms based on the characteristics of the major groups in their class. For example, humans, chimps, gorillas, and gibbons are all parts of the order Primate because they all share large brains and opposable thumbs, use tools, and have social groups. The order Rodentia includes gnawing mammals with continuously growing teeth, like squirrels, hamsters, and rats.
6. Family: Families further divided organisms of the same order by similar characteristics. For example, humans are part of the Hominidae family, where gibbons split off into their own family: Hylobatidae.
7. Genus: Two or more species that share unique body structures or other characteristics are closely related enough to be placed in a single genus. A genus may include only a single species if no other organism has characteristics similar enough for it to be considered the same genus. Here’s where humans split from gorillas; where part of the genus Homo, while they’re in the genus Gorilla.
8. Species: A species is the most specific level, so it contains the fewest types of organisms. Organisms of the same species have very similar characteristics. The human species is sapiens while a gorilla species is gorilla (and yes, that means they’re classified as Gorilla gorilla, because species are conventionally written with the genus and the species together.

Question 16

What is the best mnemonic for you to recite the classification system from the broadest (domain) to most narrow (species)?

Answer 16

“Dear King Phillip, come over for good spaghetti.”

Domain

Kingdom

Phylum

Classes

Order

Family

Genus

Species

Question 17

Most scientists agree that there are five or six kingdoms. Define and differentiate all six kingdoms.

Answer 17

1. Animals: This is one of the two largest kingdoms, and it includes many-celled organisms that, unlike plants, don’t have cell walls, chlorophyll, or the capacity to use light to make energy (photosynthesis).
2. Plants: Plants are also one of the two largest kingdoms. This kingdom includes organisms that can’t move, don’t have obvious nervous or sensory systems (the Venus flytrap is one exception), and possess cell walls made of cellulose.
3. Fungi: Examples of common fungi are mushrooms and yeast. Fungi don’t photosynthesize (use light to create energy) like plants do, but they do have cell walls made of carbohydrate called chitin.
4. Protists: Protists include one-celled organisms that do have a nucleus, such as the protozoan, which you may remember from biology class.
5. Eubacteria: This kingdom, which used to be considered Monerans, is made up of single-celled organisms that don’t have distinct nuclei or organelles (small, specialized structures within cells that act like organs). Bacteria are found everywhere, including your body and the depths of the ocean.
6. Archaebacteria: Archaea is a kingdom comprising single-celled organisms that have no distinct nuclei or organelles; they have different genetic structures and metabolic processes than bacteria do.

Question 18

How to name an organism using the taxonomic classification?

Answer 18

In italic format, a scientist must capitalize the first letter of the creature’s genus and write the creature’s species in lowercase afterwards. For example, Homo sapiens.

Question 19

Identify all the human body systems.

Answer 19

1. Nervous system
2. Cardiovascular and circulatory systems
3. Renal system and urinary system
4. Respiratory system
5. Digestive system
6. Muscular system
7. Skeletal system
8. Endocrine system
9. Lymphatic system and immune system
10. Integumentary system and exocrine system
11. Reproductive system

Question 20

What are the components of the nervous system, what does it do?

Answer 20

The components of the nervous system are cerebrum, cerebellum, medulla, spinal cord, and nerves. The nervous system receives, processes, and responds to all physical stimuli; for example, if you burn your hand on the stove, this system prompts you to remove your hand from the stove.

Question 21

What are the components of the cardiovascular and circulatory systems, and what does these systems do?

Answer 21

The components of the cardiovascular and circulatory systems are heart, arteries, veins, capillaries, and blood. These systems deliver oxygenated blood and nutrients from the heart to the rest of the body, whisks away waste products, and returns the blood to the heart to oxygenate it again.

Question 22

What are the components of the renal system and the urinary system, and what does these systems do?

Answer 22

The renal system and the urinary system filters toxins from the blood and sends them out with urine. The components of the renal system and the urinary system are kidneys, bladder, and urethra.

Question 23

What is the respiratory system and what are the components of the respiratory system?

Answer 23

The respiratory system inhales air uses the oxygen in the air to release the energy and exhales the carbon dioxide that results from this process. The components of the respiratory system are nose, nasal cavity, trachea, and lungs.

Question 24

What is the digestive system and the excretory system? Identify the components.

Answer 24

The digestive system and the excretory system break down food into smaller substances that the body can absorb and process into energy; eliminates waste from the body. The components are mouth, esophagus, stomach, and intestines.

Question 25

What is the muscular system? Identify all of its components.

Answer 25

The muscular system allows organs to contract and allows bodily movement. The components of the muscular system are smooth, cardiac, and skeletal muscles.

Question 26

What is the skeletal system and its components?

Answer 26

The skeletal system supports the body’s muscles and organs; allows the bones and joints to move. The skeletal system is composed of bones, joints, tendons, and cartilage.

Question 27

What is the endocrine system? and What are the components of the endocrine system?

Answer 27

The endocrine system communicates through hormones. The components of the endocrine system are thyroid, pituitary, adrenal, pineal, and reproductive glands; pancreas; and hormones.

Question 28

What is the lymphatic system and immune system? Identify all the components.

Answer 28

The lymphatic system and immune system help rid the body of toxins, waste, and other materials the body doesn’t need, fights infection. The components of the lymphatic and immune system are lymph nodes, spleen, tonsils, and lymph.

Question 29

What is the integumentary system and exocrine system? Identify all of the components of these systems.

Answer 29

The integumentary system and the exocrine system help the body from damage, such as overheating, injuries, abrasion, and loss of water from the outside. The components of these systems are skin, hair, nails, and exocrine glands, such as sweat glands.

Question 30

What is the reproductive system and what are the components?

Answer 30

The reproductive system enables and controls the production of offspring. The components of this system are sex organs and reproductive organs.

Question 31

Within the central nervous system, there is a brain. What are the 3 major parts of the brain? discuss its functions.

Answer 31

The 3 major parts of the brain are cerebrum, cerebellum, and the medulla. First, the cerebrum is responsible for thinking, hearing, seeing, and other functions. Second, the cerebellum is the group of nerves responsible for balance and muscle coordination. Last, the medulla connects your brain to your spinal cord, and it handles all your involuntary actions (including your heartbeat).

Question 32

Explain the flow of the blood within the circulatory system.

Answer 32

At the circulatory system’s core, the heart, a four-chambered organ that contracts and relaxes several times each minute. Two chambers collect blood coming in (each is called an atrium, but together, they’re atria). and two, called ventricles, pump it back out. Heart valves close after blood leaves, preventing it from coming back in the exit door.

When the blood leaves the heart, it rushes through arteries—the largest thickest tunnels in the circulatory system, these blood-carrying tubes have to be thick and strong, because the heart pumps out oxygenated blood fast, which creates a lot of pressure. Arteries branch out several times (each branch is called an arteriole) to send blood into the tissues through tiny tunnels called capillaries. Capillaries let out oxygen and nutrients while they take in carbon dioxide and waste in a process called diffusion (arteries and veins don’t).

Veins carry blood back to the heart, and they don’t have thick walls because they don’t need them, when blood makes its return trip, it’s not under a lot of pressure to get there quickly. The blood going back to the heart is dark red because it’s deoxygenated (it drops off all its oxygen to organs and systems when it travels from the heart).

Question 33

What is blood made out of?

Answer 33

Blood is made up of cells suspended in plasma (the liquid portion of blood).

Question 34

Where does the three kinds of blood came from. Differentiate these kinds of blood.

Answer 34

There are 3 kinds of blood: red blood cells, white blood cells, and platelets. The cells for blood are made in bone marrow (The spongy stuff inside the cavities of bones). Red blood cells carry oxygen, white blood cells fight infection, and platelets are pieces of cells that cause blood to clot.

Question 35

What the 4 types of blood? What are the laws in donating blood?

Answer 35

1. A
2. B
3. AB
4. O

which can be positive or negative.

Type O negative blood is considered the universal donor, it can be donated to anyone: in contrast, type AB positive is the universal recipient which means a person with this blood type can receive any other kind of blood.

Question 36

What is the main toxin-filtering component of your body?

Answer 36

The renal system, home to the kidneys, ureters, bladder, and urethra, is the main toxin-filtering component of your body.

Question 37

What is homeostasis?

Answer 37

Homeostasis is the body’s ability to regulate its inner environment, so it remains stable, even when outside conditions aren’t). The wonder-organs of the renal system helps the body maintain homeostasis.

Question 38

What is the process of bringing in oxygen and getting rid of carbon dioxide?

Answer 38

The process of bringing in oxygen and getting rid of carbon dioxide is respiration.

Question 39

What is pharynx?

Answer 39

The pharynx is part of the respiratory system, which usually hurts when you have a sore throat because it is a filter that catches pathogens before they go through your epiglottis (the bit that makes a mistake when you choke on food).

Question 40

What is the trachea?

Answer 40

As part of the respiratory system, the trachea is the final filter found in your Adams apple, which is the area right below the hard lump you can feel in your throat (that’s the larynx, or voice box).

Question 41

What are the bronchi, bronchioles, alveolus or alveoli?

Answer 41

The air you breathe goes into your lungs through the left and right bronchi. The bronchi separate into smaller tunnels, called bronchioles, and each one ends in a tiny sac, or alveolus (plural alveoli), that puts oxygen into your blood stream.

Question 42

In the digestive system, there is a chemical related to the gastric acids that breaks food down further into your stomach, what is it?

Answer 42

When the esophagus pushes the food into your stomach, gastric acids and a chemical called pepsin break the food down further.

Question 43

What is the difference between the small intestine and the large intestine?

Answer 43

The small intestine in a normal adult is about 23 feet long, and it produces enzymes that work with other enzymes made in the pancreas and liver to turn fat, carbs, and protein into useful substances for your body. the large intestine is about 5 feet long; it reabsorbs water and minerals into your body. the kidneys filter liquid waste and secrete it through urine. The solid waste mater letter left-over stays in your rectum until you evacuate it.

Question 44

Your body has three types of muscles. Define and differentiate all three.

Answer 44

1. Cardiac muscle is only present in your heart. The fibers of these cylindrical, involuntary muscles interlock with each other so that your heart can pump blood. Your heart muscles contract involuntarily — they act on their own, outside your control.
2. Smooth muscle is the muscle of choice for hollow organs such as your stomach, lungs, and intestines). These muscles are arranged in parallel lines to form sheets of tissue. Like cardiac muscles, smooth muscles contract involuntarily.
3. Skeletal muscle is what makes you run, jump, and use the remote control to stream your favorite TV shows. They’re striated (they appear striped under a microscope) and cylindrical. These muscles are voluntary because you can consciously decide to use them.

Question 45

What is the difference between endoskeleton and exoskeletons?

Answer 45

Humans have endoskeleton — one that’s inside the body and covered by soft tissue. Other animals (such as armadillos, grasshoppers, and lobsters) have exoskeletons that protect their soft tissue. Some animals, such as jellyfish, don’t have skeletons at all.

Question 46

What is the process called ossification?

Answer 46

The skeletal system includes bones, cartilage, ligaments, and tendons. Bones start their lives as cartilage, but over time, the cartilage is replaced by calcium and phosphorus in a process called ossification. (That is the technical term for bone formation). Cartilage is much more flexible than bone is, but because bone is still living tissue, it can repair itself when it’s damaged or broken.

Question 47

The human body has several types of joints, but they all share one thing in common: They enable two or more bones to move relative to each other. What are the seven major types of joints? Differentiate each one of them to one another.

Answer 47

1. Hinge joints, such as those at your elbows and knees, work like door hinge or the binding of a book.
2. Ball and socket joints, like those in your shoulders and hips, consist of a ball-like end that fits into a bowl-shaped receptacle. They work like a joystick allowing you a wide range of motion.
3. Pivot joints allow you to rotate one bone around another because one bone fits into a ring formed by another bone. You find them in your neck’s first and second vertebrae (that’s what allows you to move your head back and forth).
4. Fixed joints are places where two separate bones meet, but there is no room or ability for movement. your skull has fixed joints.
5. Saddle joints are joints that let you move one bone in oval motion. Rotate your thumb to see a saddle joint action.
6. Condyloid joints allow back-and-forth and side-to-side movement. You find condyloid joints in your knuckles (the ones connected to your hands bones, not the ones halfway up your fingers). they give you the range of motion you need to signal that you want five cheeseburgers and to make a fist.
7. Gliding joints occur between the surfaces of two bones held together by ligaments. They’re in your wrists and ankles and between the tiny bones in your feet.

Question 48

What is the comparison between ligaments and tendons?

Answer 48

Ligaments and tendons help your bones move so you can move. Ligaments join the bones (think of them like rubber bands), while tendons connect muscle tissue to bones and other structures in your body (like your eyeballs).

Question 49

Describe the glands of endocrine system.

Answer 49

These glands produce hormones to regulate reproduction and sexual function, growth and development, tissue function, sleep, mood, and a whole host of other actions are part of the endocrine system. This system uses hormones to communicate with organs and other glands.

Question 50

What is a lymph?

Answer 50

The body’s lymphatic and immune systems include lymph (a fluid that contains white blood cells that fight infection).

Question 51

What is the difference between bacteria and viruses?

Answer 51

Bacteria are single-celled organisms that cause illnesses such as pneumonia and staph infections. On the other hand, viruses cause illnesses like colds, COVID-19, and HIV. Antibiotics can be used to treat bacterial infections, but they don’t work on viruses, except through prevention by way of vaccines. Vaccination prevent disease by teaching the immune system how to fight specific viruses before they have a chance to reproduce.

Question 52

Disease-carrying organisms such as mosquitoes, rats, and ticks are called?

Answer 52

vectors

Question 53

Explain the integumentary system.

Answer 53

The integumentary system protects you from getting scuffed up, losing all the water in your body, and smashing your bones when you miss the nail and hit your thumb with a hammer. The largest organ in your body — your skin — is part of this essential system. It also includes your fingernails, hair, and sweat glands, as well as sebaceous glands (the ones responsible for oily skin) and ceruminous glands (the purveyors of earwax). The whole system protects you from more severe injuries, but it’s also there to produce vitamin D that your body needs.

Question 54

How does human reproduction occur?

Answer 54

Human reproduction can’t occur unless a male’s sperm fertilizes a female’s ovum. Women release an egg. from an ovary approximately once every 28 days. the egg travels down the fallopian tube and into the uterus, where it waits for fertilization. If it is not fertilized, the endometrial lining comes off in a process called menstruation — but if sperm does fertilize it, the egg turns into a zygote. if conditions are right, the zygote can implant itself in the uterus and eventually develop into a fetus.

Question 55

What do you need in order to keep your body in peak operating condition? & Why?

Answer 55

• Carbohydrates for energy: Carbohydrates come from starches and sugars, such as bread, pasta, fruit, and candy bars.
• Fats for energy: Too much fat is bad, but you do need some in your diet. Fats fall into three categories: saturated, monounsaturated, and polyunsaturated. Polyunsaturated fats are required for normal body functions, but your body can’t make them, so you have to eat foods that contain them (such as many vegetable oils, walnuts, and some fish). saturated fats come from meat, shellfish, eggs, and dairy. Monounsaturated fats come from olives, avocados, and some nuts.
• Fiber for getting rid of waste products: Leafy vegetables, beans, potatoes, and fruits have plenty of fiber.
• Minerals for various bodily functions: A few necessary minerals include iron to develop red blood cells, calcium to keep your bones strong, and potassium to keep your heart’s electrical activity in check. A well-balanced diet ensures you’re getting the minerals you need, but some people need supplements.
• Protein for growth, maintenance, and repair: Humans consume protein through meat, fish, beans, nuts, and a handful of other sources.
• Vitamins for various bodily functions: You can usually get all the 13 essential vitamins from fruits, veggies, and the sun. Your body uses them for things such as blood clotting, processing food, and regulating your hormones.
• Water to keep your cells from shriveling up and withering away: Most foods contain water, but you still need to drink water as well. Humans lose about four pints of water each day, and you have to replace it or face serious health consequences, such as headaches, cramps, and even death.

Question 56

What are the purposes of plants’ roots, stem, and leaves?

Answer 56

The purpose of a plant’s root is by bringing in nutrients and anchor the plant to the ground. The stem is like the plant’s spine, supporting it above ground and serving as a highway for nutrients and water between roots and leaves. The leaves collect energy from the sun and host the processes that make food for the plant through photosynthesis.

Question 57

Scientists usually put plants in one of four major groups based on the types of tissue they have and how they reproduce, what are these 4 major types of plants? Differentiate.

Answer 57

1. Angiosperms are flowering plants. These plants have vascular tissue (tissue that transports fluid and nutrients internally, which is similar to human veins) and produce flowers and seeds. Angiosperms include roses and all the flowers in your garden; palm trees; and apple trees.
2. Bryophytes are plants that don’t have a vascular system and don’t produce flowers or seeds. They reproduce by releasing spores. Lichen, liverwort, and many types of mosses are bryophytes.
3. Ferns are plants with vascular tissue, but they don’t produce seeds.
4. Gymnosperms are plants that produce cones and seeds rather than flowers, and they have vascular tissue, too. Your Christmas tree is a gymnosperm, as are California’s giant sequoias and most non-flowering shrubs.

Question 58

Describe the 2 plant systems, its components and functions.

Answer 58

1. Root: The components of the system root are vascular tissue, primary roots, and secondary roots (branches). The function of this system is to absorb water and nutrients from the soil, it holds the plants in place, and stores nutrients.
2. Shoot: The components of the system shoot are vascular tissue, stem, or stalk, leaves, flower, cones. The function of this system allows the plants to grow taller, absorbs light energy from the sun, converts energy, absorbs carbon dioxide, and releases oxygen.

Question 59

illustrate the anatomy of a plant.

Answer 59

Question 60

Plants make their own food through a process called __________, which takes place in the leaves.

Answer 60

Photosynthesis.

Question 61

What must the plant have in order for photosynthesis to occur?

Answer 61

In order for photosynthesis to occur, plants must have a carbon dioxide, water, and sunlight.

Question 62

Photosynthesis occurs in two stages, what are those? Differentiate.

Answer 62

1. Light-dependent reactions happens when chlorophyll (the chemical substance that makes plants green) and other pigments absorb energy from sunlight. the energy splits water molecules into hydrogen and oxygen), and the oxygen evaporates in the atmosphere when temperatures heat up. the hydrogen that’s left behind combines with carbon dioxide the plants absorb to form glucose — that’s what plants “eat.”
2. The Calvin cycle is a series of chemical reactions that take place during photosynthesis. these reactions can only happen after the plant has captured energy from sunlight.

Question 63

Plants, like all other organisms, need to reproduce. They can do so in 2 ways, what are those and differentiate?

Answer 63

They can do so sexually (when two cells carrying half the DNA necessary for a new, whole cell join) or asexually (when one cell splits into two identical cells).

Question 64

How does more advanced plants (such as angiosperms or gymnosperms) and primitive plants (such as bryophytes and ferns) reproduce?

Answer 64

1. Angiosperms are the most advanced types of plants when it comes to sexual reproduction. They create flowers that contain stigma, which produces pollen, and carpels, which catch pollen. A bug, bird, or even the wind can pick up pollen from one flower and deposit it on the stigma of the same species (or another stigma of the same plant). Each particle of pollen grain contains sperm that fertilizes an ovule (egg) in the flower.
2. Gymnosperms sexually reproduce in ways similar to angiosperms. They produce naked seeds — seeds that aren’t wrapped in a fruit or seed pod — that develop on the upper surfaces of cone scales (pine trees are gymnosperms, and pinecones are where seeds develop). Wind carries the seeds where they need to be for fertilization.
3. Bryophytes and ferns reproduce sexually and asexually. They use spores, which contain male and female reproductive organs. fertilization occurs before the plant ever releases a spore. After a plant releases a spore, the spore can grow where it lands (as long as conditions are right). Scientists believe that all plants were once spore-bearing, and only after the plants evolved and adapted to live on land did they begin to form seeds.

Question 65

Nearly all cells have four things in common. Each has…? Differentiate.

Answer 65

Each has nucleus, cytoplasm, a membrane, and ribosomes.

1. Nucleus: The nucleus (plural nuclei) controls cellular activity. It’s like the brains behind the cell, and it holds the cell’s genetic material — DNA.
2. Cytoplasm: The cytoplasm is a gel-like substance, composed mostly of water, that is inside the cell membrane and outside the nucleus. Cytoplasm contains many chemicals that carry out the life processes in the cell.
3. Cell membrane (plasma membrane): This thin membrane holds the cell together, protecting the nucleus and cytoplasm.
4. Ribosomes: Ribosomes manufacture proteins that the cell uses to perform work. They’re necessary for biochemical reactions inside cells that allow them to survive.

Question 66

Differentiate the basic structures of a plant and animal cells.

Answer 66

Question 67

How do plant cells differ from animal cells?

Answer 67

• Plant cells have a firm cell wall that supports and protects the cell. Animal cells don’t have such a structure.
• Plant cells have larger vacuoles (storage areas) than those found in animal cells.
• Unlike animal cells, many plant cells contain chloroplasts, which contain chlorophyll, a chemical that helps plants create food with the help of sunlight.
• Animal cells contain centrioles (cylindrical structures involved in cell division). Most plant and fungus cells don’t.
• Animal cells have lysosomes (sacs of enzymes), which are not found in plant cells.

Question 68

Cells perform various processes to function at an optimum level. What are the five common processes?

Answer 68

• Metabolism: Chemical processes within a cell that are necessary to maintain life.
• Osmosis: Movement of liquid through the cell membrane (and the main way that water goes in and out of cells).
• Phagocytosis: Acquisition of particles of material from outside the cell; it is accomplished by surrounding the particles and passing them through the cell membrane.
• Photosynthesis: Conversion of light energy from the sun to chemical energy that the cell can use.
• Cellular respiration: Process in which biochemical energy from nutrients turns into product the cell can use; one of the way a cell releases chemical energy to fuel its activity.

Question 69

In human genetics, what is the standard pair of chromosomes a person must have?

Answer 69

23 pairs of chromosomes.

Question 70

How does cells reproduce?

Answer 70

Most cells reproduce by mitosis, in which the nucleus of a cell divides, forming two cells and two identical sets of chromosomes. However, sex cells (eggs and sperm) reproduce differently. Through meiosis, each cell divides into four cells, each containing only half the number of chromosomes as nonsex cell. This process takes place so the sex cells of one person (with 23 chromosomes) can hook up with the sex cells of another person (with 23 chromosomes) to produce 46 chromosomes, or 23 pairs. Otherwise, way too many chromosomes would be floating around.

^{Sometimes cells don’t copy themselves and divide perfectly and a genetic difference occurs. This is frequently results in a fetus who does not live or in a fetus with a genetic disease or disorder. for example, Down syndrome is the result of a fetus’s having 47 rather than 46 chromosomes.}

Question 71

Sex chromosomes determine whether a child will be a biological male or female. How do you tell?

Answer 71

If two sex chromosomes are alike, and they are labeled XX, she is a female; in the other hand, if the chromosomes are different and are labeled XY, then he is a male.