Unit 2: Biology Flashcards

Question

Lysosomes

Answer 1

Break down waste, damaged parts and invaders. Like Lysol or garbage trucks. Mostly in animal cells

Answer 2

Plant cells have a cell wall for structure and protection. They have chloroplasts for photosynthesis. The vacuole is larger in a plant cell for water storage. Plants get energy from sunlight (chloroplasts) and animal cells get it from food (mitochondria). Plants are shaped like a box

Answer 3

Different cells have different roles or functions in an organism. Instead of every cell doing everything, each type of cells is specialized to do one specific job very well. (They start as stem cells and over time, certain genes turn on or off, causing them to specialize). Shapes are different of specialized cells (form fits function). Increases efficiency and allows complex organisms to exist.

Answer 4

Cells divide for growth and development (increases size. ex. bone growth). Repair damaged tissues. Reproduction (makes more cells). Maintaining Homeostasis (helps maintain a stable internal environment. As cells age or become damaged, they need to be replaced to ensure that the body functions optimally)

Answer 5

The process of cells dividing to make two identical daughter cells with the same number of chromosomes (46). There are 5 stages (PMATC). 1. Prophase - The chromosomes condense (become visible) - the nuclear membrane breaks down - spindle fibers start to form from centrosomes (organelle that organizes spindle fibers, like an anchor that pulls the chromosomes apart) (centrioles help form the spindle fibers) 2. Metaphase - Chromosomes line up in the middle - Spindle fibers attach to the centromeres (the part where the chromatids are joined) 3. Anaphase - Sister chromatids (half the x or chromosome) are pulled apart to opposite sides 4. Telophase - new nuclear membranes form around each set of chromosomes - chromosomes uncoil and return to the stringy form - there are two nuclei in one cell 5. Cytokinesis - the cytoplasm divides, the cell splits into two identical cells (daughter cells)

Answer 6

They spend most of their time in interphase, where they grow, replicate DNA and perform cell functions. You don't want cells with issues to divide so there are checkpoints. Interphase is divided into three sections G1 (Gap 1: normal cell function, grows to nearly full size), S (Synthesis: duplicates DNA), G2 (Gap 2: prepare for mitosis, finishes growth). There is a checkpoint in G1 (Is the cell growing well enough? Is the DNA damaged?), G2 (Was the DNA duplicated correctly? Is it growing well? Does it have the resources to continue?), and in Mitosis (In metaphase, it checks if the chromosomes are lined up in the middle correctly). If it doesn't pass the checkpoint, it tries to fix itself. If it cannot fix itself, it kills itself called apoptosis (this will also happen once a cell has divided about 50 times). G0 is a resting phase

Answer 7

- uncontrolled growth and cell division leads to a tumor which can be benign (slow growing and do not spread) or malignant (cancer and spread to other organs - starts with a damage in DNA, called a mutation) - Cells cannot communicate or perform normal cell functions - can travel and divert nutrients Possible causes include: genetic links, exposure to UV light, chemicals, toxins or radiation Treatments include: Chemotherapy (destroy cells with medication), Radiation (destroy cells with radiation), surgery)

Answer 8

The process of plants, algae and some bacteria using sunlight to make glucose and oxygen from carbon dioxide and water. 6 Carbon dioxide + 6 water + light energy --> glucose (C6H12O6) + 6 oxygen. The water comes from the soil to the roots and is transported by the xylem. CO2 comes in from the stomatas. Roots absorb water and transport to leaves. The leaves have large SA to trap sunlight. The stomata takes in air and the molecules are taken in by chloroplast and glucose is created.

Answer 9

- Cells need to make ATP - Break glucose to make ATP The process of cells breaking down glucose to release ATP, the energy cells use to function. Glucose + 6 oxygen --> 6 carbon dioxide + 6 water + ATP (energy)

Answer 10

Henrietta Lacks had cancer and went to Johns Hopkins Hospital to get treated. They took her cells and realized that they were able to live outside the body. The cells were shipped all over the world. The impact has been huge. It changed the communication - Informed consent

Answer 11

Dissolved substances or particles move from region of high concentration to low concentration (doesn't require energy). Nutrients, water, oxygen and cellular waste are transported around the cell by diffusion. Cells stay small because the volume increases and so does the distance that particles need to travel (it is a limiting factor). The most effective ratio is a high ratio of surface area to volume, which can only be achieved by being small. If you double SA, the volume will be more than doubled. The ratio of SA to volume is smaller. Therefore, cells divide because they can remain small and grow the organism.

Answer 12

Protects the body from injury, infection, and dehydration; also helps regulate body temperature. Skin: Barrier against pathogens and water loss. Hair: Provides warmth and protection. Nails: Protect fingers and toes. Sweat glands: Help cool the body. - Skin is the largest organ

Answer 13

Removes liquid wastes, toxins, and extra water from the blood. It also maintains water and salt balance (Think Excretory "Exit") Kidneys: filter blood to form urine Ureters: tubes that carry urine to the bladder Bladder: stores urine Urethra: Urine exits the body here

Answer 14

Produces and releases hormones to control growth, metabolism, mood, and other processes. Pituitary gland: “Master gland” — controls other glands. Thyroid: Controls metabolism. Adrenal glands: Handle stress (adrenaline). Pancreas: Regulates blood sugar (insulin).

Answer 15

Protects the body from pathogens (like bacteria, viruses, parasites) and fights disease. White blood cells: Destroy invaders Lymph nodes: Filter harmful substances Spleen: Filters blood and helps fight infections Bone marrow: Makes immune cells - Lymphatic system circulates immune cells The lymphatic system is a network of organs, vessels and tissues that work together to move a colourless, watery fluid (lymph) back into your circulatory system (your bloodstream)

Answer 16

Allows the body to move, maintain posture, and produce heat. Skeletal muscles: Move bones (voluntary). Smooth muscles: Found in organs (involuntary). Cardiac muscle: Found only in the heart. - Muscles work by contracting (shortening) and relaxing.

Answer 17

- Sends and receives messages; controls body functions and responds to internal and external stimuli - Coordinates all actions in your body (voluntary and involuntary). Consists of central nervous system: brain (control center) and spinal cord (connects brain to body) and the peripheral nervous system: nerves (carries electrical signals throughout the body)

Answer 18

Allows humans to reproduce and make offspring. Female Organs: Ovaries: Produce eggs and estrogen. Uterus: Where a baby develops. Vagina: Birth canal and passage for menstrual flow.

Answer 19

Gives the body structure, protects organs, makes blood cells, and helps with movement. Bones: Provide shape and support. Joints: Connect bones and allow movement. Cartilage: Cushioning tissue between bones. Ligaments: Connect bones to bones. - Bone marrow inside bones makes red blood cells.

Answer 20

The respiratory system is responsible for: Bringing oxygen (O₂) into your body (inhalation), transporting it to your blood, and removing carbon dioxide (CO₂), a waste product of cellular respiration (exhalation). Every single cell in your body needs oxygen to make energy (ATP) through a process called cellular respiration. Without oxygen, cells can’t survive for long. Steps: - Nose/Nasal Cavity 👃 Air enters here first. Lined with mucus and tiny hairs (cilia) to: Filter out dust and microbes. Warm and moisten the air. - Pharynx (Throat) A shared passage for both air and food. Directs air to the larynx and food to the esophagus. - Larynx (Voice Box) 🗣️ Contains the vocal cords. Directs air into the trachea. Prevents food from entering the lower airways using a flap called the epiglottis. - Trachea (Windpipe) 🧵 A rigid tube that connects the throat to the lungs. Has cartilage rings to keep it open. Lined with cilia and mucus to trap particles. - Bronchi → Bronchioles 🌿 The trachea splits into two bronchi (one for each lung). Each bronchus branches into smaller tubes called bronchioles. These tubes get smaller and narrower, like a tree. - Alveoli (Air Sacs) 🫧 Tiny balloon-like structures at the end of bronchioles. This is where gas exchange happens (through diffusion). They are surrounded by capillaries (tiny blood vessels). Oxygen moves into the blood, CO₂ moves out of the blood. Transport: Oxygen enters blood in the alveoli, attaches to hemoglobin in red blood cells, is carried to every cell in your body.

Answer 21

The digestive system is a group of organs that work together to: 1. Ingest (take in) food 2. Break it down into small molecules 3. Absorb nutrients into the bloodstream 4. Eliminate waste (poop) Steps: - Mouth 👄 Teeth: Break food into smaller pieces (mechanical digestion). Saliva (from salivary glands): Begins chemical digestion using enzymes like amylase (breaks down starch). Food becomes a soft, moist ball called a bolus. - Esophagus 🧵 A muscular tube that moves food from the mouth to the stomach. Uses peristalsis: wave-like muscle contractions that push food down. (The epiglottis prevents it from going down the trachea) - Stomach 🥼 A muscular, J-shaped organ. Mechanical digestion: Churns food by contracting muscular walls. Chemical digestion: Uses gastric juices (including hydrochloric acid and pepsin) to break down proteins. Food becomes a thick liquid called chyme. Sphincters separate the entrance and exit of the stomach to prevent backflow - Small Intestine 🧬 (about 20 feet long!) This is where most digestion and nutrient absorption happen. 3 parts (DJ Ivan): Duodenum: Receives chyme and digestive juices from the pancreas (enzymes) and liver (bile). Jejunum & Ileum: Absorb nutrients into the bloodstream using tiny finger-like structures called villi (and microvilli) Has villi to increase absorption (increases surface area) - Liver (Accessory Organ) 🧪 Produces bile, which breaks down fats. Stores nutrients, detoxifies chemicals, and processes drugs. - Gallbladder (Accessory Organ) 🫙 Stores and releases bile into the small intestine when fat is present. - Pancreas (Accessory Organ) 🍌 Produces digestive enzymes Releases bicarbonate to neutralize stomach acid in the small intestine. Also part of the endocrine system (makes insulin). - Large Intestine (Colon) 💧 Re-absorbs water and minerals from remaining undigested material. Contains good bacteria that help make vitamins like vitamin K. Forms solid waste (feces). - Rectum and Anus 🚽 Rectum stores feces. Anus is the opening through which waste exits the body.

Answer 22

- Blood transports hormones, nutrients and gases carries gases (gets rid of CO2 and delivers oxygen) - The heart has 4 chambers (right atrium, right ventricle, left atrium, left ventricle - ventricles have thicker walls) and it has valves to prevent back flow. Arteries carry blood away from the heart. Viens carry it back. Capillaries are tiny blood vessels through your body. - The right side of the heart (left side on paper) pumps deoxygenated blood and the left side pumps oxygenated blood - The deoxygenated blood enters the inferior vena cava (or superior vena cava, depending on the location) and enters the right atrium. The right atrium contracts sending the blood, through the valve and into the right ventricle, which contracts and sending it through the pulmonary valve and the pulmonary artery. The pulmonary artery takes the blood to the lungs, where the red blood cells will take on oxygen and release carbon dioxide. It is now oxygenated and must return to the heart to be pumped through the body. It travels to a pulmonary vein to the left atrium, it goes through a valve and enters the left ventricle. The left ventricle contracts and sends it through the aortic value to out the aorta. - The heart receives its own blood supply through the coronary arteries (a blockage of these can cause a heart attack) - the septum is the muscular wall separates left and right sides of heart

Answer 23

1. Esophagus is long and points down so food can go to the stomach. The smooth inner walls and circular muscles allow peristalsis (it is shaped to be a one way passage) 2. Lots of contact with nearby bloodstream (capillaries) 3. The small intestine is very long and narrow, to increase surface area without taking up too much space, allows for maximum nutrient absorption. 4. Gallbladder can store up to 80mL of bile

Answer 24

Organelle that organizes spindle fibers, like an anchor that pulls the chromosomes apart

Answer 25

A chromatid is one half of a duplicated chromosome. The identical copies are called sister chromatids

Answer 26

Centrioles are small, cylinder-shaped structures found in animal cells. They play a key role in cell division by helping organize the spindle fibers that move chromosomes.

Answer 27

Spindle fibers are tiny thread-like structures that help move and divide chromosomes during cell division (when one cell splits into two).

Answer 28

A chromosome is a structure inside the nucleus (center) of a cell that holds DNA, which is like a set of instructions for how your body works and grows. Humans have 46.

Answer 29

A centromere is the center point where two sister chromatids are joined together in a duplicated chromosome.

Answer 30

The lungs have millions of tiny air sacs called alveoli, which are surrounded by thin blood vessels (capillaries). This structure gives a huge surface area and thin walls, making it easy for oxygen and carbon dioxide to quickly pass between air and blood. The nose and nasal cavity is lined with tiny hairs and mucus, which filters dust and warms/humidifies air before it enters the lungs. Diaphragm (muscle under lungs) is a dome-shaped muscle that contracts and flattens to helps create space in the chest for the lungs to fill with air (inhale) and push air out (exhale).

Answer 31

- cardiac muscle (myocardium) contracts rhythmically - Contains valves (tricuspid, mitral, pulmonary, aortic) to prevent backflow. - Thicker left ventricle wall pumps blood with higher force to the whole body.

Answer 32

Plants have four major organs: leaves, flowers, roots and stem. The flower is like the reproductive system. The organs fall into two systems. The root system (stem and roots) and the shoot system (leaves and flowers). The root system has two functions: Anchors the plant (providing stability and support so the plant can stand upright and resist wind or water flow) and responsible for water and nutrient absorption (absorbs water and minerals from the soil, which are essential for photosynthesis, growth, and other plant processes). Leaves are the primary sites for photosynthesis. Stems provide structure support and allow leaves to capture sunlight effectively. They hold the vascular tissues (xylem and phloem).

Answer 33

1) vascular tissues --> make up the tubes 2) dermal tissue --> outside layer (protection) 3) ground tissue --> tissue for all the stuff in between

Unit 2: Biology Flashcards

(57 cards)